rowid,title,contents,year,author,author_slug,published,url,topic 42,An Overview of SVG Sprite Creation Techniques,"SVG can be used as an icon system to replace icon fonts. The reasons why SVG makes for a superior icon system are numerous, but we won’t be going over them in this article. If you don’t use SVG icons and are interested in knowing why you may want to use them, I recommend you check out “Inline SVG vs Icon Fonts” by Chris Coyier – it covers the most important aspects of both systems and compares them with each other to help you make a better decision about which system to choose. Once you’ve made the decision to use SVG instead of icon fonts, you’ll need to think of the best way to optimise the delivery of your icons, and ways to make the creation and use of icons faster. Just like bitmaps, we can create image sprites with SVG – they don’t look or work exactly alike, but the basic concept is pretty much the same. There are several ways to create SVG sprites, and this article will give you an overview of three of them. While we’re at it, we’re going to take a look at some of the available tools used to automate sprite creation and fallback for us. Prerequisites The content of this article assumes you are familiar with SVG. If you’ve never worked with SVG before, you may want to look at some of the introductory tutorials covering SVG syntax, structure and embedding techniques. I recommend the following: SVG basics: Using SVG. Structure: Structuring, Grouping, and Referencing in SVG — The , , and Elements. We’ll mention and quite a bit in this article. Embedding techniques: Styling and Animating SVGs with CSS. The article covers several topics, but the section linked focuses on embedding techniques. A compendium of SVG resources compiled by Chris Coyier — contains resources to almost every aspect of SVG you might be interested in. And if you’re completely new to the concept of spriting, Chris Coyier’s CSS Sprites explains all about them. Another important SVG feature is the viewBox attribute. For some of the techniques, knowing your way around this attribute is not required, but it’s definitely more useful if you understand – even if just vaguely – how it works. The last technique mentioned in the article requires that you do know the attribute’s syntax and how to use it. To learn all about viewBox, you can refer to my blog post about SVG coordinate systems. With the prerequisites in place, let’s move on to spriting SVGs! Before you sprite… In order to create an SVG sprite with your icons, you’ll of course need to have these icons ready for use. Some spriting tools require that you place your icons in a folder to which a certain spriting process is to be applied. As such, for all of the upcoming sections we’ll work on the assumption that our SVG icons are placed in a folder named SVG. Each icon is an individual .svg file. You’ll need to make sure each icon is well-prepared and optimised for use – make sure you’ve cleaned up the code by running it through one of the optimisation tools or processes available (or doing it manually if it’s not tedious). After prepping the icon files and placing them in a folder, we’re ready to create our SVG sprite. HTML inline SVG sprites Since SVG is XML code, it can be embedded inline in an HTML document as a code island using the element. Chris Coyier wrote about this technique first on CSS-Tricks. The embedded SVG will serve as a container for our icons and is going to be the actual sprite we’re going to use. So we’ll start by including the SVG in our document. Next, we’re going to place the icons inside the . Each icon will be wrapped in a element we can then reference and use elsewhere in the page using the SVG element. The element has many benefits, and we’re using it because it allows us to define a symbol (which is a convenient markup for an icon) without rendering that symbol on the screen. The elements defined inside will only be rendered when they are referenced – or called – by the element. Moreover, can have its own viewBox attribute, which makes it possible to control the positioning of its content inside its container at any time. Before we move on, I’d like to shed some light on the style=""display:none;"" part of the snippet above. Without setting the display of the SVG to none, and even though its contents are not rendered on the page, the SVG will still take up space in the page, resulting in a big empty area. In order to avoid that, we’re hiding the SVG entirely with CSS. Now, suppose we have a Twitter icon in the icons folder. twitter.svg might look something like this: We don’t need the root svg element, so we’ll strip the code and only keep the parts that make up the Twitter icon’s shape, which in this example is just the element.Let’s drop that into the sprite container like so: Repeat for the other icons. The value of the element’s viewBox attribute depends on the size of the SVG. You don’t need to know how the viewBox works to use it in this case. Its value is made up of four parts: the first two will almost always be “0 0”; the second two will be equal to the size of the icon. For example, our Twitter icon is 32px by 32px (see twitter.svg above), so the viewBox value is “0 0 32 32”. That said, it is certainly useful to understand how the viewBox works – it can help you troubleshoot SVG sometimes and gives you better control over it, allowing you to scale, position and even crop SVGs manually without having to resort to an editor. My blog post explains all about the viewBox attribute and its related attributes. Once you have your SVG sprite ready, you can display the icons anywhere on the page by referencing them using the SVG element: And that’s all there is to it! HTML-inline SVG sprites are simple to create and use, but when you have a lot of icons (and the more icon sets you create) it can easily become daunting if you have to manually transfer the icons into the . Fortunately, you don’t have to do that. Fabrice Weinberg created a Grunt plugin called grunt-svgstore which takes the icons in your SVG folder and generates the SVG sprites for you; all you have to do is just drop the sprites into your page and use the icons like we did earlier. This technique works in all browsers supporting SVG. There seems to be a bug in Safari on iOS which causes the icons not to show up when the SVG sprite is defined at the bottom of the document after the references to the icons, so it’s safest to include the sprite before you use the icons until this bug is fixed. This technique has one disadvantage: the SVG sprite cannot be cached. We’re saving an extra HTTP request here but the browser cannot cache the image, so we aren’t speeding up any subsequent page loads by inlining the SVG. There must be a better way – and there is. Styling the icons is possible, but getting deep into the styles becomes a bit harder owing to the nature of the contents of the element – these contents are cloned into a shadow DOM, and hence selecting elements in CSS the traditional way is not possible. However, some techniques to work around that do exist, and give us slightly more styling flexibility. Animations work as expected. Referencing an external SVG sprite in HTML Instead of including the SVG inline in the document, you can reference the sprite and the icons inside it externally, taking advantage of fragment identifiers to select individual icons in the sprite. For example, the above reference to the Twitter icon would look something like this instead: icons.svg is the name of the SVG file that contains all of our icons as symbols, and the fragment identifier #twitter-icon is the reference to the wrapping the Twitter icon’s contents. Very convenient, isn’t it? The browser will request the sprite and then cache it, speeding up subsequent page loads. Win! This technique also works in all browsers supporting SVG except Internet Explorer – not even IE9+ with SVG support permits this technique. No version of IE supports referencing an external SVG in . Fortunately (again), Jonathan Neil has created a plugin called svg4everybody which fills this gap in IE; you can reference an external sprite in and also provide fallback for browsers that do not support SVG. However, it requires you to have the fallback images (PNG or JPEG, for example) available to do so. For details, refer to the plugin’s Github repository’s readme file. CSS inline SVG sprites Another way to create an SVG sprite is by inlining the SVG icons in a style sheet using data URIs, and providing fallback for non-supporting browsers – also within the CSS. Using this approach, we’re turning the style sheet into the sprite that includes our icons. The style sheet is normally cached by the browser, so we have that concern out of the way. This technique is put into practice in Filament Group’s icon system approach, which uses their Grunticon plugin – or its sister Grumpicon web app – for generating the necessary CSS for the sprite. As such, we’re going to cover this technique by following a workflow that uses one of these tools. Again, we start with our icon SVG files. To focus on the actual spriting method and not on the tooling, I’ll go over the process of sprite creation using the Grumpicon web app, instead of the Grunticon plugin. Both tools generate the same resources that we’re going to use for the icon system. Whether you choose the web app or the Grunt set-up, after processing your SVG folder you’re going to end up with the same set of resources that we’ll be using throughout this section. The first step is to drop your icons into the Grumpicon web app. Grumpicon homepage screenshot. The application will then show you a preview of your icons, and a download button will allow you to download the generated files. These files will contain everything you need for your icon system – all that’s left is for you to drop the generated files and code into your project as recommended and you’ll have your sprite and icons ready to use anywhere you want in your page. Grumpicon generates five files and one folder in the downloaded package: a png folder containing PNG versions of your icons; three style sheets (that we’ll go over briefly); a loader script file; and preview.html which is a live example showing you the other files in action. The script in the loader goes into the of your page. This script handles browser and feature detection, and requests the necessary style sheet depending on browser support for SVG and base64 data URIs. If you view the source code of the preview page, you can see exactly how the script is added. icons.data.svg.css is the style sheet that contains your icons – the sprite. The icons are embedded inline inside the style sheet using data URIs, and applied to elements of your choice as background images, using class names. For example: .twitter-icon{ background-image: url('data:image/svg+xml;…'); /* the ellipsis is where the icon’s data would go */ background-repeat: no-repeat; background-position: 50% 50%; height: 2em; width: 2em; /* etc. */ } Then, you only have to apply the twitter-icon class name to an element in your HTML to apply the icon as a background to it: And that’s all you need to do to get an icon on the page. icons.data.svg.css, along with the other two style sheets and the png folder should be added to your CSS folder. icons.data.png.css is the style sheet the script will load in browsers that don’t support SVG, such as IE8. Fallback for the inline SVG is provided as a base64-encoded PNG. For instance, the fallback for the Twitter icon from our example would look like so: .twitter-icon{ background-image: url('data:image/png;base64;…’); /* etc. */ } icons.fallback.css is the style sheet required for browsers that don’t support base64-encoded PNGs – the PNG images are loaded as usual using the image’s URL. The script will load this style sheet for IE6 and IE7, for example. .twitter-icon{ background-image: url(png/twitter-icon.png); /* etc. */ } This technique is very different from the previous one. The sprite in this case is literally the style sheet, not an SVG container, and the icon usage is very similar to that of a CSS sprite – the icons are provided as background images. This technique has advantages and disadvantages. For the sake of brevity, I won’t go into further details, but the main limitations worth mentioning are that SVGs embedded as background images cannot be styled with CSS; and animations are restricted to those defined inside the for each icon. CSS interactions (such as hover effects) don’t work either. Thus, to apply an effect for an icon that changes its color on hover, for example, you’ll need to export a set of SVGs for each colour in order for Grumpicon to create matching fallback PNG images that can then be used for the animation. For more details about the Grumpicon workflow, I recommend you check out “A Designer’s Guide to Grumpicon” on Filament Group’s website. Using SVG fragment identifiers and views This spriting technique is, again, different from the previous ones, and it is my personal favourite. SVG comes with a standard way of cropping to a specific area in a particular SVG image. If you’ve ever worked with CSS sprites before then this definitely sounds familiar: it’s almost exactly what we do with CSS sprites – the image containing all of the icons is cropped, so to speak, to show only the one icon that we want in the background positioning area of the element, using background size and positioning properties. Instead of using background properties, we’ll be using SVG’s viewBox attribute to crop our SVG to the specific icon we want. What I like about this technique is that it is more visual than the previous ones. Using this technique, the SVG sprite is treated like an actual image containing other images (the icons), instead of treating it as a piece of code containing other code. Again, our SVG icons are placed inside a main SVG container that is going to be our SVG sprite. If you’re working in a graphics editor, position or arrange your icons inside the canvas any way you want them to be, and then export the graphic as is. Of course, the less empty space there is in your SVG, the better. In our example, the sprite contains three icons as shown in the following image. The sprite is open in Sketch. Notice how the SVG is just big enough to fit the icons inside it. It doesn’t have to be like this, but it’s cleaner this way. Screenshot showing the SVG sprite containing our icons. Now, suppose you want to display only the Instagram icon. Using the SVG viewBox attribute, we can crop the SVG to the icon. The Instagram icon is positioned at 64px along the positive x-axis, and zero pixels along the y-axis. It is also 32px by 32px in size. Screenshot showing the position (offset) of the Instagram icon inside the SVG sprite, and its size. Using this information, we can specify the value of the viewBox as: 64 0 32 32. This area of the view box contains only the Instagram icon. 64 0 specifies the top-left corner of the view box area, and 32 32 specify its dimensions. Now, if we were to change the viewBox value on the SVG sprite to this value, only the Instagram icon will be visible inside the SVG viewport. Great. But how do we use this information to display the icon in our page using our sprite? SVG comes with a native way to link to portions or areas of an image using fragment identifiers. Fragment identifiers are used to link into a particular view area of an SVG document. Thus, using a fragment identifier and the boundaries of the area that we want (from the viewBox), we can link to that area and display it. For example, if you want to display the icon from the sprite using an tag, you can reference the icon in the sprite like so: The fragment identifier in the snippet above (#svgView(viewBox(64, 0, 32, 32))) is the important part. This will result in only the Instagram icon’s area of the sprite being displayed. There is also another way to do this, using the SVG element. The element can be used to define a view area and then reference that area somewhere else. For example, to define the view box containing the Instagram icon, we can do the following: Then, we can reference this view in our element like this: The best part about this technique – besides the ability to reference an external SVG and hence make use of browser caching – is that it allows us to use practically any SVG embedding technique and does not restrict us to specific tags. It goes without saying that this feature can be used for more than just icon systems, owing to viewBox’s power in controlling an SVG’s viewable area. SVG fragment identifiers have decent browser support, but the technique is buggy in Safari: there is a bug that causes problems when loading a server SVG file and then using fragment identifiers with it. Bear Travis has documented the issue and a workaround. Where to go from here Pick the technique that works best for your project. Each technique has its own pros and cons, relating to convenience and maintainability, performance, and styling and scripting. Each technique also requires its own fallback mechanism. The spriting techniques mentioned here are not the only techniques available. Other methods exist, such as SVG stacks, and others may surface in future, but these are the three main ones today. The third technique using SVG’s built-in viewBox features is my favourite, and with better browser support and fewer (ideally, no) bugs, I believe it is more likely to become the standard way to create and use SVG sprites. Fallback techniques can be created, of course, in one of many possible ways. Do you use SVG for your icon system? If so, which is your favourite technique? Do you know or have worked with other ways for creating SVG sprites?",2014,Sara Soueidan,sarasoueidan,2014-12-16T00:00:00+00:00,https://24ways.org/2014/an-overview-of-svg-sprite-creation-techniques/,code 23,Animating Vectors with SVG,"It is almost 2014 and fifteen years ago the W3C started to develop a web-based scalable vector graphics (SVG) format. As web technologies go, this one is pretty old and well entrenched. See the Pen yJflC by Drew McLellan (@drewm) on CodePen Embed not working on your device? Try direct. Unlike rasterized images, SVG files will stay crisp and sharp at any resolution. With high-DPI phones, tablets and monitors, all those rasterized icons are starting to look a bit old and blocky. There are several options to get simpler, decorative pieces to render smoothly and respond to various device widths, shapes and sizes. Symbol fonts are one option; the other is SVG. I’m a big fan of SVG. SVG is an XML format, which means it is possible to write by hand or to script. The most common way to create an SVG file is through the use of various drawing applications like Illustrator, Inkscape or Sketch. All of them open and save the SVG format. But, if SVG is so great, why doesn’t it get more attention? The simple answer is that for a long time it wasn’t well supported, so no one touched the technology. SVG’s adoption has always been hampered by browser support, but that’s not the case any more. Every modern browser (at least three versions back) supports SVG. Even IE9. Although the browsers support SVG, it is implemented in many different ways. SVG in HTML Some browsers allow you to embed SVG right in the HTML: the element. Treating SVG as a first-class citizen works — sometimes. Another way to embed SVG is via the element; using the src attribute, you can refer to an SVG file. Again, this only works sometimes and leaves you in a tight space if you need to have a fallback for older browsers. The most common solution is to use the element, with the data attribute referencing the SVG file. When a browser does not support this, it falls back to the content inside the . This could be a rasterized fallback . This method gets you the best of both worlds: a nice vector image with an alternative rasterized image for browsers that don’t support SVG. The downside is that you need to manage both formats, and some browsers will download both the SVG and the rasterized version, becoming a performance problem. Alexey Ten came up with a brilliant little trick that uses inline SVG combined with an SVG element. This has an SVG href pointing to the vector SVG representation and a src attribute to the rasterized version. Older browsers will rewrite the element as and use the rasterized src attribute, but modern browsers will show the vector SVG. It is a great workaround for most situations. You will have to determine the browsers you want or need to support and consider performance issues to decide which method is best for you. So it can be used in HTML. Why? There are two compelling reasons why vector graphics in the form of icons and symbols are going to be important on the web. With higher resolution screens, going from 72dpi to 200, 300, even over 400dpi, your rasterized icons are looking a little too blocky. As we zoom and print, we expect the visuals on the site to also stay smooth and crisp. The other main reason vector graphics are useful is scaling. As responsive websites become the norm, we need a way to dynamically readjust the heights, widths and styles of various elements. SVG handles this perfectly, since vectors remain smooth when changing size. SVG files are text-based, so they’re small and can be gzipped nicely. There are also techniques for creating SVG sprites to further squeeze out performance gains. But SVG really shines when you begin to couple it with JavaScript. Since SVG elements are part of the DOM, they can be interacted with just like any other element you are used to. The folks at Vox Media had an ingenious little trick with their SVG for a Playstation and Xbox One reviews. I’ve used the same technique for the 24 ways example. Vox Media spent a lot of time creating SVG line art of the two consoles, but once in place the artwork scaled and resized beautifully. They still had another trick up their sleeves. In their example, they knew each console was line art, so they used SVG’s line dash property to simulate the lines being drawn by animating the growth of the line by small percentage increments until the lines were complete. This is a great example of a situation where the alternatives wouldn’t be as straightforward to implement. Using an animated GIF would create a heavy file since it would need to contain all the frames of the animation at a large size to permit scaling; even then, smooth aliasing would be lost. canvas and plenty of JavaScript would be another alternative, but this is a rasterized format. It would need be redrawn at each scale, which is certainly possible, but smoothness would be lost when zooming or printing. The HTML, SVG and JavaScript for this example is less than 4KB! Let’s have a quick look at the code: First, we need to initialize a few variables to set the current frame, the number of frames, how fast the animation will run, and we get each of the paths based on their IDs. With those paths, we set the dash and dash offset. path[i].style.strokeDasharray = l + ' ' + l; path[i].style.strokeDashoffset = l; We start the line as a dash, which effectively makes it blank or invisible. Next, we move to the draw() function. This is where the magic happens. We want to increment the frame to move us forward in the animation and check it’s not finished. If it continues, we then take a percentage of the distance based on the frame and then set the dash offset to this new percentage. This gives the illusion that the line is being drawn. Then we have an animation callback, which starts the draw process over again. That’s it! It will work with any SVG element that you can draw. Libraries to get you started If you aren’t sure where to start with SVG, there are several libraries out there to help. They also abstract all browser compatibility issues to make your life easier. Raphaël Snap.svg svg.js You can also get most vector applications to export SVG. This means that you can continue your normal workflows, but instead of flattening the image as a PNG or bringing it over to Photoshop to rasterize, you can keep all your hard work as vectors and reap the benefits of SVG.",2013,Brian Suda,briansuda,2013-12-07T00:00:00+00:00,https://24ways.org/2013/animating-vectors-with-svg/, 61,Animation in Responsive Design,"Animation and responsive design can sometimes feel like they’re at odds with each other. Animation often needs space to do its thing, but RWD tells us that the amount of space we’ll have available is going to change a lot. Balancing that can lead to some tricky animation situations. Embracing the squishiness of responsive design doesn’t have to mean giving up on your creative animation ideas. There are three general techniques that can help you balance your web animation creativity with your responsive design needs. One or all of these approaches might help you sneak in something just a little extra into your next project. Focused art direction Smaller viewports mean a smaller stage for your motion to play out on, and this tends to amplify any motion in your animation. Suddenly 100 pixels is really far and multiple moving parts can start looking like they’re battling for space. An effect that looked great on big viewports can become muddled and confusing when it’s reframed in a smaller space. Making animated movements smaller will do the trick for simple motion like a basic move across the screen. But for more complex animation on smaller viewports, you’ll need to simplify and reduce the number of moving parts. The key to this is determining what the vital parts of the animation are, to zone in on the parts that are most important to its message. Then remove the less necessary bits to distill the motion’s message down to the essentials. For example, Rally Interactive’s navigation folds down into place with two triangle shapes unfolding each corner on larger viewports. If this exact motion was just scaled down for narrower spaces the two corners would overlap as they unfolded. It would look unnatural and wouldn’t make much sense. Open video The main purpose of this animation is to show an unfolding action. To simplify the animation, Rally unfolds only one side for narrower viewports, with a slightly different animation. The action is still easily interpreted as unfolding and it’s done in a way that is a better fit for the available space. The message the motion was meant to convey has been preserved while the amount of motion was simplified. Open video Si Digital does something similar. The main concept of the design is to portray the studio as a creative lab. On large viewports, this is accomplished primarily through an animated illustration that runs the full length of the site and triggers its animations based on your scroll position. The illustration is there to support the laboratory concept visually, but it doesn’t contain critical content. Open video At first, it looks like Si Digital just turned off the animation of the illustration for smaller viewports. But they’ve actually been a little cleverer than that. They’ve also reduced the complexity of the illustration itself. Both the amount of motion (reduced down to no motion) and the illustration were simplified to create a result that is much easier to glean the concept from. Open video The most interesting thing about these two examples is that they’re solved more with thoughtful art direction than complex code. Keeping the main concept of the animations at the forefront allowed each to adapt creative design solutions to viewports of varying size without losing the integrity of their design. Responsive choreography Static content gets moved around all the time in responsive design. A three-column layout might line up from left to right on wide viewports, then stack top to bottom on narrower viewports. The same approach can be used to arrange animated content for narrower views, but the animation’s choreography also needs to be adjusted for the new layout. Even with static content, just scaling it down or zooming out to fit it into the available space is rarely an ideal solution. Rearranging your animations’ choreography to change which animation starts when, or even which animations play at all, keeps your animated content readable on smaller viewports. In a recent project I had three small animations that played one after the other, left to right, on wider viewports but needed to be stacked on narrower viewports to be large enough to see. On wide viewports, all three animations could play one right after the other in sequence because all three were in the viewable area at the same time. But once these were stacked for the narrower viewport layouts, that sequence had to change. Open video What was essentially one animation on wider viewports became three separate animations when stacked on narrower viewports. The layout change meant the choreography had to change as well. Each animation starts independently when it comes into view in the stacked layout instead of playing automatically in sequence. (I’ve put the animated parts in this demo if you want to peek under the hood.) Open video I choose to use the GreenSock library, with the choreography defined in two different timelines for this particular project. But the same goals could be accomplished with other JavaScript options or even CSS keyframe animations and media queries. Even more complex responsive choreography can be pulled off with SVG. Media queries can be used to change CSS animations applied to SVG elements at specific breakpoints for starters. For even more responsive power, SVG’s viewBox property, and the positioning of the objects within it, can be adjusted at JavaScript-defined breakpoints. This lets you set rules to crop the viewable area and arrange your animating elements to fit any space. Sarah Drasner has some great examples of how to use this technique with style in this responsive infographic and this responsive interactive illustration. On the other hand, if smart scalability is what you’re after, it’s also possible to make all of an SVG’s shapes and motion scale with the SVG canvas itself. Sarah covers both these clever responsive SVG techniques in detail. Creative and complex animation can easily become responsive thanks to the power of SVG! Open video Bake performance into your design decisions It’s hard to get very far into a responsive design discussion before performance comes up. Performance goes hand in hand with responsive design and your animation decisions can have a big impact on the overall performance of your site. The translate3D “hack”, backface-visibility:hidden, and the will-change property are the heavy hitters of animation performance. But decisions made earlier in your animation design process can have a big impact on rendering performance and your performance budget too. Pick a technology that matches your needs One of the biggest advantages of the current web animation landscape is the range of tools we have available to us. We can use CSS animations and transitions to add just a dash of interface animation to our work, go all out with webGL to create a 3D experience, or anywhere in between. All within our browsers! Having this huge range of options is amazing and wonderful but it also means you need to be cognizant of what you’re using to get the job done. Loading in the full weight of a robust JavaScript animation library is going to be overkill if you’re only animating a few small elements here and there. That extra overhead will have an impact on performance. Performance budgets will not be pleased. Always match the complexity of the technology you choose to the complexity of your animation needs to avoid unnecessary performance strain. For small amounts of animation, stick to CSS solutions since it’s the most lightweight option. As your animations grow in complexity, or start to require more robust logic, move to a JavaScript solution that can accomplish what you need. Animate the most performant properties Whether you’re animating in CSS or JavaScript, you’re affecting specific properties of the animated element. Browsers can animate some properties more efficiently than others based on how many steps need to happen behind the scenes to visually update those properties. Browsers are particularly efficient at animating opacity, scale, rotation, and position (when the latter three are done with transforms). This article from Paul Irish and Paul Lewis gives the full scoop on why. Conveniently, those are also the most common properties used in motion design. There aren’t many animated effects that can’t be pulled off with this list. Stick to these properties to set your animations up for the best performance results from the start. If you find yourself needing to animate a property outside of this list, check CSS Triggers… to find out how much of an additional impact it might have. Offset animation start times Offsets (the concept of having a series of similar movements execute one slightly after the other, creating a wave-like pattern) are a long-held motion graphics trick for creating more interesting and organic looking motion. Employing this trick of the trade can also be smart for performance. Animating a large number of objects all at the same time can put a strain on the browser’s rendering abilities even in the best cases. Adding short delays to offset these animations in time, so they don’t all start at once, can improve rendering performance. Go explore the responsive animation possibilities for yourself! With smart art direction, responsive choreography, and an eye on performance you can create just about any creative web animation you can think up while still being responsive. Keep these in mind for your next project and you’ll pull off your animations with style at any viewport size!",2015,Val Head,valhead,2015-12-09T00:00:00+00:00,https://24ways.org/2015/animation-in-responsive-design/,design 70,Bringing Your Code to the Streets,"— or How to Be a Street VJ Our amazing world of web code is escaping out of the browser at an alarming rate and appearing in every aspect of the environment around us. Over the past few years we’ve already seen JavaScript used server-side, hardware coded with JavaScript, a rise of native style and desktop apps created with HTML, CSS and JavaScript, and even virtual reality (VR) is getting its fair share of front-end goodness. You can go ahead and play with JavaScript-powered hardware such as the Tessel or the Espruino to name a couple. Just check out the Tessel project page to see JavaScript in the world of coffee roasting or sleep tracking your pet. With the rise of the internet of things, JavaScript can be seen collecting information on flooding among other things. And if that’s not enough ‘outside the browser’ implementations, Node.js servers can even be found in aircraft! I previously mentioned VR and with three.js’s extra StereoEffect.js module it’s relatively simple to get browser 3D goodness to be Google Cardboard-ready, and thus set the stage for all things JavaScript and VR. It’s been pretty popular in the art world too, with interactive works such as Seb Lee-Delisle’s Lunar Trails installation, featuring the old arcade game Lunar Lander, which you can now play in your browser while others watch (it is the web after all). The Science Museum in London held Chrome Web Lab, an interactive exhibition featuring five experiments, showcasing the magic of the web. And it’s not even the connectivity of the web that’s being showcased; we can even take things offline and use web code for amazing things, such as fighting Ebola. One thing is for sure, JavaScript is awesome. Hell, if you believe those telly programs (as we all do), JavaScript can even take down the stock market, purely through the witchcraft of canvas! Go JavaScript! Now it’s our turn So I wanted to create a little project influenced by this theme, and as it’s Christmas, take it to the streets for a little bit of party fun! Something that could take code anywhere. Here’s how I made a portable visual projection pack, a piece of video mixing software and created some web-coded street art. Step one: The equipment You will need: One laptop: with HDMI output and a modern browser installed, such as Google Chrome. One battery-powered mini projector: I’ve used a Texas Instruments DLP; for its 120 lumens it was the best cost-to-lumens ratio I could find. One MIDI controller (optional): mine is an ICON iDJ as it suits mixing visuals. However, there is more affordable hardware on the market such as an Akai LPD8 or a Korg nanoPAD2. As you’ll see in the article, this is optional as it can be emulated within the software. A case to carry it all around in. Step two: The software The projected visuals, I imagined, could be anything you can create within a browser, whether that be simple HTML and CSS, images, videos, SVG or canvas. The only requirement I have is that they move or change with sound and that I can mix any one visual into another. You may remember a couple of years ago I created a demo on this very site, allowing audio-triggered visuals from the ambient sounds your device mic was picking up. That was a great starting point – I used that exact method to pick up the audio and thus the first requirement was complete. If you want to see some more examples of visuals I’ve put together for this, there’s a showcase on CodePen. The second requirement took a little more thought. I needed two screens, which could at any point show any of the visuals I had coded, but could be mixed from one into the other and back again. So let’s start with two divs, both absolutely positioned so they’re on top of each other, but at the start the second screen’s opacity is set to zero. Now all we need is a slider, which when moved from one side to the other slowly sets the second screen’s opacity to 1, thereby fading it in. See the Pen Mixing Screens (Software Version) by Rumyra (@Rumyra) on CodePen. Mixing Screens (CodePen) As you saw above, I have a MIDI controller and although the software method works great, I’d quite like to make use of this nifty piece of kit. That’s easily done with the Web MIDI API. All I need to do is call it, and when I move one of the sliders on the controller (I’ve allocated the big cross fader in the middle for this), pick up on the change of value and use that to control the opacity instead. var midi, data; // start talking to MIDI controller if (navigator.requestMIDIAccess) { navigator.requestMIDIAccess({ sysex: false }).then(onMIDISuccess, onMIDIFailure); } else { alert(“No MIDI support in your browser.”); } // on success function onMIDISuccess(midiData) { // this is all our MIDI data midi = midiData; var allInputs = midi.allInputs.values(); // loop over all available inputs and listen for any MIDI input for (var input = allInputs.next(); input && !input.done; input = allInputs.next()) { // when a MIDI value is received call the onMIDIMessage function input.value.onmidimessage = onMIDIMessage; } } function onMIDIMessage(message) { // data comes in the form [command/channel, note, velocity] data = message.data; // Opacity change for screen. The cross fader values are [176, 8, {0-127}] if ( (data[0] === 176) && (data[1] === 8) ) { // this value will change as the fader is moved var opacity = data[2]/127; screenTwo.style.opacity = opacity; } } The final code was slightly more complicated than this, as I decided to switch the two screens based on the frequencies of the sound that was playing, and use the cross fader to depict the frequency threshold value. This meant they flickered in and out of each other, rather than just faded. There’s a very rough-and-ready first version of the software on GitHub. Phew, Great! Now we need to get all this to the streets! Step three: Portable kit Did you notice how I mentioned a case to carry it all around in? I wanted the case to be morphable, so I could use the equipment from it too, a sort of bag-to-usherette-tray-type affair. Well, I had an unused laptop bag… I strengthened it with some MDF, so when I opened the bag it would hold like a tray where the laptop and MIDI controller would sit. The projector was Velcroed to the external pocket of the bag, so when it was a tray it would project from underneath. I added two durable straps, one for my shoulders and one round my waist, both attached to the bag itself. There was a lot of cutting and trimming. As it was a laptop bag it was pretty thick to start and sewing was tricky. However, I only broke one sewing machine needle; I’ve been known to break more working with leather, so I figured I was doing well. By the way, you can actually buy usherette trays, but I just couldn’t resist hacking my own :) Step four: Take to the streets First, make sure everything is charged – everything – a lot! The laptop has to power both the MIDI controller and the projector, and although I have a mobile phone battery booster pack, that’ll only charge the projector should it run out. I estimated I could get a good hour of visual artistry before I needed to worry, though. I had a couple of ideas about time of day and location. Here in the UK at this time of year, it gets dark around half past four, so I could easily head out in a city around 5pm and it would be dark enough for the projections to be seen pretty well. I chose Bristol, around the waterfront, as there were some interesting locations to try it out in. The best was Millennium Square: busy but not crowded and plenty of surfaces to try projecting on to. My first time out with the portable audio/visual pack (PAVP as it will now be named) was brilliant. I played music and projected visuals, like a one-woman band of A/V! You might be thinking what the point of this was, besides, of course, it being a bit of fun. Well, this project got me to look at canvas and SVG more closely. The Web MIDI API was really interesting; MIDI as a data format has some great practical uses. I think without our side projects we may not have all these wonderful uses for our everyday code. Not only do they remind us coding can, and should, be fun, they also help us learn and grow as makers. My favourite part? When I was projecting into a water feature in Millennium Square. For those who are familiar, you’ll know it’s like a wall of water so it produced a superb effect. I drew quite a crowd and a kid came to stand next to me and all I could hear him say with enthusiasm was, ‘Oh wow! That’s so cool!’ Yes… yes, kid, it was cool. Making things with code is cool. Massive thanks to the lovely Drew McLellan for his incredibly well-directed photography, and also Simon Johnson who took a great hand in perfecting the kit while it was attached.",2015,Ruth John,ruthjohn,2015-12-06T00:00:00+00:00,https://24ways.org/2015/bringing-your-code-to-the-streets/,code 283,"CSS3 Patterns, Explained","Many of you have probably seen my CSS3 patterns gallery. It became very popular throughout the year and it showed many web developers how powerful CSS3 gradients really are. But how many really understand how these patterns are created? The biggest benefit of CSS-generated backgrounds is that they can be modified directly within the style sheet. This benefit is void if we are just copying and pasting CSS code we don’t understand. We may as well use a data URI instead. Important note In all the examples that follow, I’ll be using gradients without a vendor prefix, for readability and brevity. However, you should keep in mind that in reality you need to use all the vendor prefixes (-moz-, -ms-, -o-, -webkit-) as no browser currently implements them without a prefix. Alternatively, you could use -prefix-free and have the current vendor prefix prepended at runtime, only when needed. The syntax described here is the one that browsers currently implement. The specification has since changed, but no browser implements the changes yet. If you are interested in what is coming, I suggest you take a look at the dev version of the spec. If you are not yet familiar with CSS gradients, you can read these excellent tutorials by John Allsopp and return here later, as in the rest of the article I assume you already know the CSS gradient basics: CSS3 Linear Gradients CSS3 Radial Gradients The main idea I’m sure most of you can imagine the background this code generates: background: linear-gradient(left, white 20%, #8b0 80%); It’s a simple gradient from one color to another that looks like this: See this example live As you probably know, in this case the first 20% of the container’s width is solid white and the last 20% is solid green. The other 60% is a smooth gradient between these colors. Let’s try moving these color stops closer to each other: background: linear-gradient(left, white 30%, #8b0 70%); See this example live background: linear-gradient(left, white 40%, #8b0 60%); See this example live background: linear-gradient(left, white 50%, #8b0 50%); See this example live Notice how the gradient keeps shrinking and the solid color areas expanding, until there is no gradient any more in the last example. We can even adjust the position of these two color stops to control where each color abruptly changes into another: background: linear-gradient(left, white 30%, #8b0 30%); See this example live background: linear-gradient(left, white 90%, #8b0 90%); See this example live What you need to take away from these examples is that when two color stops are at the same position, there is no gradient, only solid colors. Even without going any further, this trick is useful for a number of different use cases like faux columns or the effect I wanted to achieve in my homepage or the -prefix-free page where the background is only shown on one side and hidden on the other: Combining with background-size We can do wonders, however, if we combine this with the CSS3 background-size property: background: linear-gradient(left, white 50%, #8b0 50%); background-size: 100px 100px; See this example live And there it is. We just created the simplest of patterns: (vertical) stripes. We can remove the first parameter (left) or replace it with top and we’ll get horizontal stripes. However, let’s face it: Horizontal and vertical stripes are kinda boring. Most stripey backgrounds we see on the web are diagonal. So, let’s try doing that. Our first attempt would be to change the angle of the gradient to something like 45deg. However, this results in an ugly pattern like this: See this example live Before reading on, think for a second: why didn’t this produce the desired result? Can you figure it out? The reason is that the gradient angle rotates the gradient inside each tile, not the tiled background as a whole. However, didn’t we have the same problem the first time we tried to create diagonal stripes with an image? And then we learned that every stripe has to be included twice, like so: So, let’s try to create that effect with CSS gradients. It’s essentially what we tried before, but with more color stops: background: linear-gradient(45deg, white 25%, #8b0 25%, #8b0 50%, white 50%, white 75%, #8b0 75%); background-size:100px 100px; See this example live And there we have our stripes! An easy way to remember the order of the percentages and colors it is that you always have two of the same in succession, except the first and last color. Note: Firefox for Mac also needs an additional 100% color stop at the end of any pattern with more than two stops, like so: ..., white 75%, #8b0 75%, #8b0). The bug was reported in February 2011 and you can vote for it and track its progress at Bugzilla. Unfortunately, this is essentially a hack and we will realize that if we try to change the gradient angle to 60deg: See this example live Not that maintainable after all, eh? Luckily, CSS3 offers us another way of declaring such backgrounds, which not only helps this case but also results in much more concise code: background: repeating-linear-gradient(60deg, white, white 35px, #8b0 35px, #8b0 70px); See this example live In this case, however, the size has to be declared in the color stop positions and not through background-size, since the gradient is supposed to cover the entire container. You might notice that the declared size is different from the one specified the previous way. This is because the size of the stripes is measured differently: in the first example we specify the dimensions of the tile itself; in the second, the width of the stripes (35px), which is measured diagonally. Multiple backgrounds Using only one gradient you can create stripes and that’s about it. There are a few more patterns you can create with just one gradient (linear or radial) but they are more or less boring and ugly. Almost every pattern in my gallery contains a number of different backgrounds. For example, let’s create a polka dot pattern: background: radial-gradient(circle, white 10%, transparent 10%), radial-gradient(circle, white 10%, black 10%) 50px 50px; background-size:100px 100px; See this example live Notice that the two gradients are almost the same image, but positioned differently to create the polka dot effect. The only difference between them is that the first (topmost) gradient has transparent instead of black. If it didn’t have transparent regions, it would effectively be the same as having a single gradient, as the topmost gradient would obscure everything beneath it. There is an issue with this background. Can you spot it? This background will be fine for browsers that support CSS gradients but, for browsers that don’t, it will be transparent as the whole declaration is ignored. We have two ways to provide a fallback, each for different use cases. We have to either declare another background before the gradient, like so: background: black; background: radial-gradient(circle, white 10%, transparent 10%), radial-gradient(circle, white 10%, black 10%) 50px 50px; background-size:100px 100px; or declare each background property separately: background-color: black; background-image: radial-gradient(circle, white 10%, transparent 10%), radial-gradient(circle, white 10%, transparent 10%); background-size:100px 100px; background-position: 0 0, 50px 50px; The vigilant among you will have noticed another change we made to our code in the last example: we altered the second gradient to have transparent regions as well. This way background-color serves a dual purpose: it sets both the fallback color and the background color of the polka dot pattern, so that we can change it with just one edit. Always strive to make code that can be modified with the least number of edits. You might think that it will never be changed in that way but, almost always, given enough time, you’ll be proved wrong. We can apply the exact same technique with linear gradients, in order to create checkerboard patterns out of right triangles: background-color: white; background-image: linear-gradient(45deg, black 25%, transparent 25%, transparent 75%, black 75%), linear-gradient(45deg, black 25%, transparent 25%, transparent 75%, black 75%); background-size:100px 100px; background-position: 0 0, 50px 50px; See this example live Using the right units Don’t use pixels for the sizes without any thought. In some cases, ems make much more sense. For example, when you want to make a lined paper background, you want the lines to actually follow the text. If you use pixels, you have to change the size every time you change font-size. If you set the background-size in ems, it will naturally follow the text and you will only have to update it if you change line-height. Is it possible? The shapes that can be achieved with only one gradient are: stripes right triangles circles and ellipses semicircles and other shapes formed from slicing ellipses horizontally or vertically You can combine several of them to create squares and rectangles (two right triangles put together), rhombi and other parallelograms (four right triangles), curves formed from parts of ellipses, and other shapes. Just because you can doesn’t mean you should Technically, anything can be crafted with these techniques. However, not every pattern is suitable for it. The main advantages of this technique are: no extra HTTP requests short code human-readable code (unlike data URIs) that can be changed without even leaving the CSS file. Complex patterns that require a large number of gradients are probably better left to SVG or bitmap images, since they negate almost every advantage of this technique: they are not shorter they are not really comprehensible – changing them requires much more effort than using an image editor They still save an HTTP request, but so does a data URI. I have included some very complex patterns in my gallery, because even though I think they shouldn’t be used in production (except under very exceptional conditions), understanding how they work and coding them helps somebody understand the technology in much more depth. Another rule of thumb is that if your pattern needs shapes to obscure parts of other shapes, like in the star pattern or the yin yang pattern, then you probably shouldn’t use it. In these patterns, changing the background color requires you to also change the color of these shapes, making edits very tedious. If a certain pattern is not practicable with a reasonable amount of CSS, that doesn’t mean you should resort to bitmap images. SVG is a very good alternative and is supported by all modern browsers. Browser support CSS gradients are supported by Firefox 3.6+, Chrome 10+, Safari 5.1+ and Opera 11.60+ (linear gradients since Opera 11.10). Support is also coming in Internet Explorer when IE10 is released. You can get gradients in older WebKit versions (including most mobile browsers) by using the proprietary -webkit-gradient(), if you really need them. Epilogue I hope you find these techniques useful for your own designs. If you come up with a pattern that’s very different from the ones already included, especially if it demonstrates a cool new technique, feel free to send a pull request to the github repo of the patterns gallery. Also, I’m always fascinated to see my techniques put in practice, so if you made something cool and used CSS patterns, I’d love to know about it! Happy holidays!",2011,Lea Verou,leaverou,2011-12-16T00:00:00+00:00,https://24ways.org/2011/css3-patterns-explained/,code 311,Designing Imaginative Style Guides,"(Living) style guides and (atomic) patterns libraries are “all the rage,” as my dear old Nana would’ve said. If articles and conference talks are to be believed, making and using them has become incredibly popular. I think there are plenty of ways we can improve how style guides look and make them better at communicating design information to creatives without it getting in the way of information that technical people need. Guides to libraries of patterns Most of my consulting work and a good deal of my creative projects now involve designing style guides. I’ve amassed a huge collection of brand guidelines and identity manuals as well as, more recently, guides to libraries of patterns intended to help designers and developers make digital products and websites. Two pages from one of my Purposeful style guide packs. Designs © Stuff & Nonsense. “Style guide” is an umbrella term for several types of design documentation. Sometimes we’re referring to static style or visual identity guides, other times voice and tone. We might mean front-end code guidelines or component/pattern libraries. These all offer something different but more often than not they have something in common. They look ugly enough to have been designed by someone who enjoys configuring a router. OK, that was mean, not everyone’s going to think an unimaginative style guide design is a problem. After all, as long as a style guide contains information people need, how it looks shouldn’t matter, should it? Inspiring not encyclopaedic Well here’s the thing. Not everyone needs to take the same information away from a style guide. If you’re looking for markup and styles to code a ‘media’ component, you’re probably going to be the technical type, whereas if you need to understand the balance of sizes across a typographic hierarchy, you’re more likely to be a creative. What you need from a style guide is different. Sure, some people1 need rules: “Do this (responsive pattern)” or “don’t do that (auto-playing video.)” Those people probably also want facts: “Use this (hexadecimal value)” and not that inaccessible colour combination.” Style guides need to do more than list facts and rules. They should demonstrate a design, not just document its parts. The best style guides are inspiring not encyclopaedic. I’ll explain by showing how many style guides currently present information about colour. Colours communicate I’m sure you’ll agree that alongside typography, colour’s one of the most important ingredients in a design. Colour communicates personality, creates mood and is vital to an easily understandable interactive vocabulary. So you’d think that an average style guide would describe all this in any number of imaginative ways. Well, you’d be disappointed, because the most inspiring you’ll find looks like a collection of chips from a paint chart. Lonely Planet’s Rizzo does a great job of separating its Design Elements from UI Components, and while its ‘Click to copy’ colour values are a thoughtful touch, you’ll struggle to get a feeling for Lonely Planet’s design by looking at their colour chips. Lonely Planet’s Rizzo style guide. Lonely Planet approach is a common way to display colour information and it’s one that you’ll also find at Greenpeace, Sky, The Times and on countless more style guides. Greenpeace, Sky and The Times style guides. GOV.UK—not a website known for its creative flair—varies this approach by using circles, which I find strange as circles don’t feature anywhere else in its branding or design. On the plus side though, their designers have provided some context by categorising colours by usage such as text, links, backgrounds and more. GOV.UK style guide. Google’s Material Design offers an embarrassment of colours but most helpfully it also advises how to combine its primary and accent colours into usable palettes. Google’s Material Design. While the ability to copy colour values from a reference might be all a technical person needs, designers need to understand why particular colours were chosen as well as how to use them. Inspiration not documentation Few style guides offer any explanation and even less by way of inspiring examples. Most are extremely vague when they describe colour: “Use colour as a presentation element for either decorative purposes or to convey information.” The Government of Canada’s Web Experience Toolkit states, rather obviously. “Certain colors have inherent meaning for a large majority of users, although we recognize that cultural differences are plentiful.” Salesforce tell us, without actually mentioning any of those plentiful differences. I’m also unsure what makes the Draft U.S. Web Design Standards colours a “distinctly American palette” but it will have to work extremely hard to achieve its goal of communicating “warmth and trustworthiness” now. In Canada, “bold and vibrant” colours reflect Alberta’s “diverse landscape.” Adding more colours to their palette has made Adobe “rich, dynamic, and multi-dimensional” and at Skype, colours are “bold, colourful (obviously) and confident” although their style guide doesn’t actually provide information on how to use them. The University of Oxford, on the other hand, is much more helpful by explaining how and why to use their colours: “The (dark) Oxford blue is used primarily in general page furniture such as the backgrounds on the header and footer. This makes for a strong brand presence throughout the site. Because it features so strongly in these areas, it is not recommended to use it in large areas elsewhere. However it is used more sparingly in smaller elements such as in event date icons and search/filtering bars.” OpenTable style guide. The designers at OpenTable have cleverly considered how to explain the hierarchy of their brand colours by presenting them and their supporting colours in various size chips. It’s also obvious from OpenTable’s design which colours are primary, supporting, accent or neutral without them having to say so. Art directing style guides For the style guides I design for my clients, I go beyond simply documenting their colour palette and type styles and describe visually what these mean for them and their brand. I work to find distinctive ways to present colour to better represent the brand and also to inspire designers. For example, on a recent project for SunLife, I described their palette of colours and how to use them across a series of art directed pages that reflect the lively personality of the SunLife brand. Information about HEX and RGB values, Sass variables and when to use their colours for branding, interaction and messaging is all there, but in a format that can appeal to both creative and technical people. SunLife style guide. Designs © Stuff & Nonsense. Purposeful style guides If you want to improve how you present colour information in your style guides, there’s plenty you can do. For a start, you needn’t confine colour information to the palette page in your style guide. Find imaginative ways to display colour across several pages to show it in context with other parts of your design. Here are two CSS gradient filled ‘cover’ pages from my Purposeful style sheets. Colour impacts other elements too, including typography, so make sure you include colour information on those pages, and vice-versa. Purposeful. Designs © Stuff & Nonsense. A visual hierarchy can be easier to understand than labelling colours as ‘primary,’ ‘supporting,’ or ‘accent,’ so find creative ways to present that hierarchy. You might use panels of different sizes or arrange boxes on a modular grid to fill a page with colour. Don’t limit yourself to rectangular colour chips, use circles or other shapes created using only CSS. If irregular shapes are a part of your brand, fill SVG silhouettes with CSS and then wrap text around them using CSS shapes. Purposeful. Designs © Stuff & Nonsense. Summing up In many ways I’m as frustrated with style guide design as I am with the general state of design on the web. Style guides and pattern libraries needn’t be dull in order to be functional. In fact, they’re the perfect place for you to try out new ideas and technologies. There’s nowhere better to experiment with new properties like CSS Grid than on your style guide. The best style guide designs showcase new approaches and possibilities, and don’t simply document the old ones. Be as creative with your style guide designs as you are with any public-facing part of your website. Purposeful are HTML and CSS style guides templates designed to help you develop creative style guides and pattern libraries for your business or clients. Save time while impressing your clients by using easily customisable HTML and CSS files that have been designed and coded to the highest standards. Twenty pages covering all common style guide components including colour, typography, buttons, form elements, and tables, plus popular pattern library components. Purposeful style guides will be available to buy online in January. Boring people ↩",2016,Andy Clarke,andyclarke,2016-12-13T00:00:00+00:00,https://24ways.org/2016/designing-imaginative-style-guides/,design 246,Designing Your Site Like It’s 1998,"It’s 20 years to the day since my wife and I started Stuff & Nonsense, our little studio and my outlet for creative ideas on the web. To celebrate this anniversary—and my fourteenth contribution to 24 ways— I’d like to explain how I would’ve developed a design for Planes, Trains and Automobiles, one of my favourite Christmas films. My design for Planes, Trains and Automobiles is fixed at 800px wide. Developing a framework I’ll start by using frames to set up the framework for this new website. Frames are individual pages—one for navigation, the other for my content—pulled together to form a frameset. Space is limited on lower-resolution screens, so by using frames I can ensure my navigation always remains visible. I can include any number of frames inside a element. I add two rows to my ; the first is for my navigation and is 50px tall, the second is for my content and will resize to fill any available space. As I don’t want frame borders or any space between my frames, I set frameborder and framespacing attributes to 0: […] Next I add the source of my two frame documents. I don’t want people to be able to resize or scroll my navigation, so I add the noresize attribute to that frame: I do want links from my navigation to open in the content frame, so I give each a name so I can specify where I want links to open: The framework for this website is simple as it contains only two horizontal rows. Should I need a more complex layout, I can nest as many framesets—and as many individual documents—as I need: Letterbox framesets were common way to deal with multiple screen sizes. In a letterbox, the central frameset had a fixed height and width, while the frames on the top, right, bottom, and left expanded to fill any remaining space. Handling older browsers Sadly not every browser supports frames, so I should send a helpful message to people who use older browsers asking them to upgrade. Happily, I can do that using noframes content: <body> <p>This page uses frames, but your browser doesn’t support them. Please upgrade your browser.</p> </body> Forcing someone back into a frame Sometimes, someone may follow a link to a page from a portal or search engine, or they might attempt to open it in a new window or tab. If that page properly belongs inside a , people could easily miss out on other parts of a design. This short script will prevent this happening and because it’s vanilla Javascript, it doesn’t require a library such as jQuery: Laying out my page Before starting my layout, I add a few basic background and colour styles. I must include these attributes in every page on my website: I want absolute control over how people experience my design and don’t want to allow it to stretch, so I first need a which limits the width of my layout to 800px. The align attribute will keep this
in the centre of someone’s screen:
[…]
Although they were developed for displaying tabular information, the cells and rows which make up the element make it ideal for the precise implementation of a design. I need several tables—often nested inside each other—to implement my design. These include tables for a banner and three rows of content:
[…]
[…]
[…]
[…]
The width of the first table—used for my banner—is fixed to match the logo it contains. As I don’t need borders, padding, or spacing between these cells, I use attributes to remove them:
The next table—which contains the largest image, introduction, and a call-to-action—is one of the most complex parts of my design, so I need to ensure its layout is pixel perfect. To do that I add an extra row at the top of this table and fill each of its cells with tiny transparent images: The height and width of these “shims” or “spacers” is only 1px but they will stretch to any size without increasing their weight on the page. This makes them perfect for performant website development. For the hero of this design, I splice up the large image into three separate files and apply each slice as a background to the table cells. I also match the height of those cells to the background images:   […]   I use tables and spacer images throughout the rest of this design to lay out the various types of content with perfect precision. For example, to add a single-pixel border around my two columns of content, I first apply a blue background to an outer table along with 1px of cellspacing, then simply nest an inner table—this time with a white background—inside it:
[…]
Adding details Tables are fabulous tools for laying out a page, but they’re also useful for implementing details on those pages. I can use a table to add a gradient background, rounded corners, and a shadow to the button which forms my “Buy the DVD” call-to-action. First, I splice my button graphic into three slices; two fixed-width rounded ends, plus a narrow gradient which stretches and makes this button responsive. Then, I add those images as backgrounds and use spacers to perfectly size my button:
Buy the DVD
I use those same elements to add details to headlines and lists too. Adding a “bullet” to each item in a list needs only two additional table cells, a circular graphic, and a spacer:
    Directed by John Hughes
Implementing a typographic hierarchy So far I’ve explained how to use frames, tables, and spacers to develop a layout for my content, but what about styling that content? I use elements to change the typeface from the browser’s default to any font installed on someone’s device: Planes, Trains and Automobiles is a comedy film […] To adjust the size of those fonts, I use the size attribute and a value between the smallest (1) and the largest (7) where 3 is the browser’s default. I use a size of 4 for this headline and 2 for the text which follows: Steve Martin An American actor, comedian, writer, producer, and musician. When I need to change the typeface, perhaps from a sans-serif like Arial to a serif like Times New Roman, I must change the value of the face attribute on every element on all pages on my website. NB: I use as many
elements as needed to create space between headlines and paragraphs. View the final result (and especially the source.) My modern day design for Planes, Trains and Automobiles. I can imagine many people reading this and thinking “This is terrible advice because we don’t develop websites like this in 2018.” That’s true. We have the ability to embed any number of web fonts into our products and websites and have far more control over type features, leading, ligatures, and sizes: font-variant-caps: titling-caps; font-variant-ligatures: common-ligatures; font-variant-numeric: oldstyle-nums; Grid has simplified the implementation of even the most complex compound grid down to just a few lines of CSS: body { display: grid; grid-template-columns: 3fr 1fr 2fr 2fr 1fr 3fr; grid-template-rows: auto; grid-column-gap: 2vw; grid-row-gap: 1vh; } Flexbox has made it easy to develop flexible components such as navigation links: nav ul { display: flex; } nav li { flex: 1; } Just one line of CSS can create multiple columns of fluid type: main { column-width: 12em; } CSS Shapes enable text to flow around irregular shapes including polygons: [src*=""main-img""] { float: left; shape-outside: polygon(…); } Today, we wouldn’t dream of using images and a table to add a gradient, rounded corners, and a shadow to a button or link, preferring instead: .btn { background: linear-gradient(#8B1212, #DD3A3C); border-radius: 1em; box-shadow: 0 2px 4px 0 rgba(0,0,0,0.50), inset 0 -1px 1px 0 rgba(0,0,0,0.50); } CSS Custom Properties, feature and media queries, filters, pseudo-elements, and SVG; the list of advances in HTML, CSS, and other technologies goes on. So does our understanding of how best to use them by separating content, structure, presentation, and behaviour. As 2018 draws to a close, we’re certain we know how to design and develop products and websites better than we did at the end of 1998. Strange as it might seem looking back, in 1998 we were also certain our techniques and technologies were the best for the job. That’s why it’s dangerous to believe with absolute certainty that the frameworks and tools we increasingly rely on today—tools like Bootstrap, Bower, and Brunch, Grunt, Gulp, Node, Require, React, and Sass—will be any more relevant in the future than elements, frames, layout tables, and spacer images are today. I have no prediction for what the web will be like twenty years from now. However, I want to believe we’ll build on what we’ve learned during these past two decades about the importance of accessibility, flexibility, and usability, and that the mistakes we made while infatuated by technologies won’t be repeated. Head over to my website if you’d like to read about how I’d implement my design for ‘Planes, Trains and Automobiles’ today.",2018,Andy Clarke,andyclarke,2018-12-23T00:00:00+00:00,https://24ways.org/2018/designing-your-site-like-its-1998/,code 288,Displaying Icons with Fonts and Data- Attributes,"Traditionally, bitmap formats such as PNG have been the standard way of delivering iconography on websites. They’re quick and easy, and it also ensures they’re as pixel crisp as possible. Bitmaps have two drawbacks, however: multiple HTTP requests, affecting the page’s loading performance; and a lack of scalability, noticeable when the page is zoomed or viewed on a screen with a high pixel density, such as the iPhone 4 and 4S. The requests problem is normally solved by using CSS sprites, combining the icon set into one (physically) large image file and showing the relevant portion via background-position. While this works well, it can get a bit fiddly to specify all the positions. In particular, scalability is still an issue. A vector-based format such as SVG sounds ideal to solve this, but browser support is still patchy. The rise and adoption of web fonts have given us another alternative. By their very nature, they’re not only scalable, but resolution-independent too. No need to specify higher resolution graphics for high resolution screens! That’s not all though: Browser support: Unlike a lot of new shiny techniques, they have been supported by Internet Explorer since version 4, and, of course, by all modern browsers. We do need several different formats, however! Design on the fly: The font contains the basic graphic, which can then be coloured easily with CSS – changing colours for themes or :hover and :focus styles is done with one line of CSS, rather than requiring a new graphic. You can also use CSS3 properties such as text-shadow to add further effects. Using -webkit-background-clip: text;, it’s possible to use gradient and inset shadow effects, although this creates a bitmap mask which spoils the scalability. Small file size: specially designed icon fonts, such as Drew Wilson’s Pictos font, can be as little as 12Kb for the .woff font. This is because they contain fewer characters than a fully fledged font. You can see Pictos being used in the wild on sites like Garrett Murray’s Maniacal Rage. As with all formats though, it’s not without its disadvantages: Icons can only be rendered in monochrome or with a gradient fill in browsers that are capable of rendering CSS3 gradients. Specific parts of the icon can’t be a different colour. It’s only appropriate when there is an accompanying text to provide meaning. This can be alleviated by wrapping the text label in a tag (I like to use rather than , due to the fact that it’s smaller and isn’ t being used elsewhere) and then hiding it from view with text-indent:-999em. Creating an icon font can be a complex and time-consuming process. While font editors can carry out hinting automatically, the best results are achieved manually. Unless you’re adept at creating your own fonts, you’re restricted to what is available in the font. However, fonts like Pictos will cover the most common needs, and icons are most effective when they’re using familiar conventions. The main complaint about using fonts for icons is that it can mean adding a meaningless character to our markup. The good news is that we can overcome this by using one of two methods – CSS generated content or the data-icon attribute – in combination with the :before and :after pseudo-selectors, to keep our markup minimal and meaningful. Our simple markup looks like this: View Basket Note the multiple class attributes. Next, we’ll import the Pictos font using the @font-face web fonts property in CSS: @font-face { font-family: 'Pictos'; src: url('pictos-web.eot'); src: local('☺'), url('pictos-web.woff') format('woff'), url('pictos-web.ttf') format('truetype'), url('pictos-web.svg#webfontIyfZbseF') format('svg'); } This rather complicated looking set of rules is (at the time of writing) the most bulletproof way of ensuring as many browsers as possible load the font we want. We’ll now use the content property applied to the :before pseudo-class selector to generate our icon. Once again, we’ll use those multiple class attribute values to set common icon styles, then specific styles for .basket. This helps us avoid repeating styles: .icon { font-family: 'Pictos'; font-size: 22px: } .basket:before { content: ""$""; } What does the :before pseudo-class do? It generates the dollar character in a browser, even when it’s not present in the markup. Using the generated content approach means our markup stays simple, but we’ll need a new line of CSS, defining what letter to apply to each class attribute for every icon we add. data-icon is a new alternative approach that uses the HTML5 data- attribute in combination with CSS attribute selectors. This new attribute lets us add our own metadata to elements, as long as its prefixed by data- and doesn’t contain any uppercase letters. In this case, we want to use it to provide the letter value for the icon. Look closely at this markup and you’ll see the data-icon attribute. View Basket We could add others, in fact as many as we like. Favourites History Location Then, we need just one CSS attribute selector to style all our icons in one go: .icon:before { content: attr(data-icon); /* Insert your fancy colours here */ } By placing our custom attribute data-icon in the selector in this way, we can enable CSS to read the value of that attribute and display it before the element (in this case, the anchor tag). It saves writing a lot of CSS rules. I can imagine that some may not like the extra attribute, but it does keep it out of the actual content – generated or not. This could be used for all manner of tasks, including a media player and large simple illustrations. See the demo for live examples. Go ahead and zoom the page, and the icons will be crisp, with the exception of the examples that use -webkit-background-clip: text as mentioned earlier. Finally, it’s worth pointing out that with both generated content and the data-icon method, the letter will be announced to people using screen readers. For example, with the shopping basket icon above, the reader will say “dollar sign view basket”. As accessibility issues go, it’s not exactly the worst, but could be confusing. You would need to decide whether this method is appropriate for the audience. Despite the disadvantages, icon fonts have huge potential.",2011,Jon Hicks,jonhicks,2011-12-12T00:00:00+00:00,https://24ways.org/2011/displaying-icons-with-fonts-and-data-attributes/,code 249,Fast Autocomplete Search for Your Website,"Every website deserves a great search engine - but building a search engine can be a lot of work, and hosting it can quickly get expensive. I’m going to build a search engine for 24 ways that’s fast enough to support autocomplete (a.k.a. typeahead) search queries and can be hosted for free. I’ll be using wget, Python, SQLite, Jupyter, sqlite-utils and my open source Datasette tool to build the API backend, and a few dozen lines of modern vanilla JavaScript to build the interface. Try it out here, then read on to see how I built it. First step: crawling the data The first step in building a search engine is to grab a copy of the data that you plan to make searchable. There are plenty of potential ways to do this: you might be able to pull it directly from a database, or extract it using an API. If you don’t have access to the raw data, you can imitate Google and write a crawler to extract the data that you need. I’m going to do exactly that against 24 ways: I’ll build a simple crawler using wget, a command-line tool that features a powerful “recursive” mode that’s ideal for scraping websites. We’ll start at the https://24ways.org/archives/ page, which links to an archived index for every year that 24 ways has been running. Then we’ll tell wget to recursively crawl the website, using the --recursive flag. We don’t want to fetch every single page on the site - we’re only interested in the actual articles. Luckily, 24 ways has nicely designed URLs, so we can tell wget that we only care about pages that start with one of the years it has been running, using the -I argument like this: -I /2005,/2006,/2007,/2008,/2009,/2010,/2011,/2012,/2013,/2014,/2015,/2016,/2017 We want to be polite, so let’s wait for 2 seconds between each request rather than hammering the site as fast as we can: --wait 2 The first time I ran this, I accidentally downloaded the comments pages as well. We don’t want those, so let’s exclude them from the crawl using -X ""/*/*/comments"". Finally, it’s useful to be able to run the command multiple times without downloading pages that we have already fetched. We can use the --no-clobber option for this. Tie all of those options together and we get this command: wget --recursive --wait 2 --no-clobber -I /2005,/2006,/2007,/2008,/2009,/2010,/2011,/2012,/2013,/2014,/2015,/2016,/2017 -X ""/*/*/comments"" https://24ways.org/archives/ If you leave this running for a few minutes, you’ll end up with a folder structure something like this: $ find 24ways.org 24ways.org 24ways.org/2013 24ways.org/2013/why-bother-with-accessibility 24ways.org/2013/why-bother-with-accessibility/index.html 24ways.org/2013/levelling-up 24ways.org/2013/levelling-up/index.html 24ways.org/2013/project-hubs 24ways.org/2013/project-hubs/index.html 24ways.org/2013/credits-and-recognition 24ways.org/2013/credits-and-recognition/index.html ... As a quick sanity check, let’s count the number of HTML pages we have retrieved: $ find 24ways.org | grep index.html | wc -l 328 There’s one last step! We got everything up to 2017, but we need to fetch the articles for 2018 (so far) as well. They aren’t linked in the /archives/ yet so we need to point our crawler at the site’s front page instead: wget --recursive --wait 2 --no-clobber -I /2018 -X ""/*/*/comments"" https://24ways.org/ Thanks to --no-clobber, this is safe to run every day in December to pick up any new content. We now have a folder on our computer containing an HTML file for every article that has ever been published on the site! Let’s use them to build ourselves a search index. Building a search index using SQLite There are many tools out there that can be used to build a search engine. You can use an open-source search server like Elasticsearch or Solr, a hosted option like Algolia or Amazon CloudSearch or you can tap into the built-in search features of relational databases like MySQL or PostgreSQL. I’m going to use something that’s less commonly used for web applications but makes for a powerful and extremely inexpensive alternative: SQLite. SQLite is the world’s most widely deployed database, even though many people have never even heard of it. That’s because it’s designed to be used as an embedded database: it’s commonly used by native mobile applications and even runs as part of the default set of apps on the Apple Watch! SQLite has one major limitation: unlike databases like MySQL and PostgreSQL, it isn’t really designed to handle large numbers of concurrent writes. For this reason, most people avoid it for building web applications. This doesn’t matter nearly so much if you are building a search engine for infrequently updated content - say one for a site that only publishes new content on 24 days every year. It turns out SQLite has very powerful full-text search functionality built into the core database - the FTS5 extension. I’ve been doing a lot of work with SQLite recently, and as part of that, I’ve been building a Python utility library to make building new SQLite databases as easy as possible, called sqlite-utils. It’s designed to be used within a Jupyter notebook - an enormously productive way of interacting with Python code that’s similar to the Observable notebooks Natalie described on 24 ways yesterday. If you haven’t used Jupyter before, here’s the fastest way to get up and running with it - assuming you have Python 3 installed on your machine. We can use a Python virtual environment to ensure the software we are installing doesn’t clash with any other installed packages: $ python3 -m venv ./jupyter-venv $ ./jupyter-venv/bin/pip install jupyter # ... lots of installer output # Now lets install some extra packages we will need later $ ./jupyter-venv/bin/pip install beautifulsoup4 sqlite-utils html5lib # And start the notebook web application $ ./jupyter-venv/bin/jupyter-notebook # This will open your browser to Jupyter at http://localhost:8888/ You should now be in the Jupyter web application. Click New -> Python 3 to start a new notebook. A neat thing about Jupyter notebooks is that if you publish them to GitHub (either in a regular repository or as a Gist), it will render them as HTML. This makes them a very powerful way to share annotated code. I’ve published the notebook I used to build the search index on my GitHub account. ​ Here’s the Python code I used to scrape the relevant data from the downloaded HTML files. Check out the notebook for a line-by-line explanation of what’s going on. from pathlib import Path from bs4 import BeautifulSoup as Soup base = Path(""/Users/simonw/Dropbox/Development/24ways-search"") articles = list(base.glob(""*/*/*/*.html"")) # articles is now a list of paths that look like this: # PosixPath('...24ways-search/24ways.org/2013/why-bother-with-accessibility/index.html') docs = [] for path in articles: year = str(path.relative_to(base)).split(""/"")[1] url = 'https://' + str(path.relative_to(base).parent) + '/' soup = Soup(path.open().read(), ""html5lib"") author = soup.select_one("".c-continue"")[""title""].split( ""More information about"" )[1].strip() author_slug = soup.select_one("".c-continue"")[""href""].split( ""/authors/"" )[1].split(""/"")[0] published = soup.select_one("".c-meta time"")[""datetime""] contents = soup.select_one("".e-content"").text.strip() title = soup.find(""title"").text.split("" ◆"")[0] try: topic = soup.select_one( '.c-meta a[href^=""/topics/""]' )[""href""].split(""/topics/"")[1].split(""/"")[0] except TypeError: topic = None docs.append({ ""title"": title, ""contents"": contents, ""year"": year, ""author"": author, ""author_slug"": author_slug, ""published"": published, ""url"": url, ""topic"": topic, }) After running this code, I have a list of Python dictionaries representing each of the documents that I want to add to the index. The list looks something like this: [ { ""title"": ""Why Bother with Accessibility?"", ""contents"": ""Web accessibility (known in other fields as inclus..."", ""year"": ""2013"", ""author"": ""Laura Kalbag"", ""author_slug"": ""laurakalbag"", ""published"": ""2013-12-10T00:00:00+00:00"", ""url"": ""https://24ways.org/2013/why-bother-with-accessibility/"", ""topic"": ""design"" }, { ""title"": ""Levelling Up"", ""contents"": ""Hello, 24 ways. Iu2019m Ashley and I sell property ins..."", ""year"": ""2013"", ""author"": ""Ashley Baxter"", ""author_slug"": ""ashleybaxter"", ""published"": ""2013-12-06T00:00:00+00:00"", ""url"": ""https://24ways.org/2013/levelling-up/"", ""topic"": ""business"" }, ... My sqlite-utils library has the ability to take a list of objects like this and automatically create a SQLite database table with the right schema to store the data. Here’s how to do that using this list of dictionaries. import sqlite_utils db = sqlite_utils.Database(""/tmp/24ways.db"") db[""articles""].insert_all(docs) That’s all there is to it! The library will create a new database and add a table to it called articles with the necessary columns, then insert all of the documents into that table. (I put the database in /tmp/ for the moment - you can move it to a more sensible location later on.) You can inspect the table using the sqlite3 command-line utility (which comes with OS X) like this: $ sqlite3 /tmp/24ways.db sqlite> .headers on sqlite> .mode column sqlite> select title, author, year from articles; title author year ------------------------------ ------------ ---------- Why Bother with Accessibility? Laura Kalbag 2013 Levelling Up Ashley Baxte 2013 Project Hubs: A Home Base for Brad Frost 2013 Credits and Recognition Geri Coady 2013 Managing a Mind Christopher 2013 Run Ragged Mark Boulton 2013 Get Started With GitHub Pages Anna Debenha 2013 Coding Towards Accessibility Charlie Perr 2013 ... There’s one last step to take in our notebook. We know we want to use SQLite’s full-text search feature, and sqlite-utils has a simple convenience method for enabling it for a specified set of columns in a table. We want to be able to search by the title, author and contents fields, so we call the enable_fts() method like this: db[""articles""].enable_fts([""title"", ""author"", ""contents""]) Introducing Datasette Datasette is the open-source tool I’ve been building that makes it easy to both explore SQLite databases and publish them to the internet. We’ve been exploring our new SQLite database using the sqlite3 command-line tool. Wouldn’t it be nice if we could use a more human-friendly interface for that? If you don’t want to install Datasette right now, you can visit https://search-24ways.herokuapp.com/ to try it out against the 24 ways search index data. I’ll show you how to deploy Datasette to Heroku like this later in the article. If you want to install Datasette locally, you can reuse the virtual environment we created to play with Jupyter: ./jupyter-venv/bin/pip install datasette This will install Datasette in the ./jupyter-venv/bin/ folder. You can also install it system-wide using regular pip install datasette. Now you can run Datasette against the 24ways.db file we created earlier like so: ./jupyter-venv/bin/datasette /tmp/24ways.db This will start a local webserver running. Visit http://localhost:8001/ to start interacting with the Datasette web application. If you want to try out Datasette without creating your own 24ways.db file you can download the one I created directly from https://search-24ways.herokuapp.com/24ways-ae60295.db Publishing the database to the internet One of the goals of the Datasette project is to make deploying data-backed APIs to the internet as easy as possible. Datasette has a built-in command for this, datasette publish. If you have an account with Heroku or Zeit Now, you can deploy a database to the internet with a single command. Here’s how I deployed https://search-24ways.herokuapp.com/ (running on Heroku’s free tier) using datasette publish: $ ./jupyter-venv/bin/datasette publish heroku /tmp/24ways.db --name search-24ways -----> Python app detected -----> Installing requirements with pip -----> Running post-compile hook -----> Discovering process types Procfile declares types -> web -----> Compressing... Done: 47.1M -----> Launching... Released v8 https://search-24ways.herokuapp.com/ deployed to Heroku If you try this out, you’ll need to pick a different --name, since I’ve already taken search-24ways. You can run this command as many times as you like to deploy updated versions of the underlying database. Searching and faceting Datasette can detect tables with SQLite full-text search configured, and will add a search box directly to the page. Take a look at http://search-24ways.herokuapp.com/24ways-b607e21/articles to see this in action. ​ SQLite search supports wildcards, so if you want autocomplete-style search where you don’t need to enter full words to start getting results you can add a * to the end of your search term. Here’s a search for access* which returns articles on accessibility: http://search-24ways.herokuapp.com/24ways-ae60295/articles?_search=acces%2A A neat feature of Datasette is the ability to calculate facets against your data. Here’s a page showing search results for svg with facet counts calculated against both the year and the topic columns: http://search-24ways.herokuapp.com/24ways-ae60295/articles?_search=svg&_facet=year&_facet=topic Every page visible via Datasette has a corresponding JSON API, which can be accessed using the JSON link on the page - or by adding a .json extension to the URL: http://search-24ways.herokuapp.com/24ways-ae60295/articles.json?_search=acces%2A Better search using custom SQL The search results we get back from ../articles?_search=svg are OK, but the order they are returned in is not ideal - they’re actually being returned in the order they were inserted into the database! You can see why this is happening by clicking the View and edit SQL link on that search results page. This exposes the underlying SQL query, which looks like this: select rowid, * from articles where rowid in ( select rowid from articles_fts where articles_fts match :search ) order by rowid limit 101 We can do better than this by constructing a custom SQL query. Here’s the query we will use instead: select snippet(articles_fts, -1, 'b4de2a49c8', '8c94a2ed4b', '...', 100) as snippet, articles_fts.rank, articles.title, articles.url, articles.author, articles.year from articles join articles_fts on articles.rowid = articles_fts.rowid where articles_fts match :search || ""*"" order by rank limit 10; You can try this query out directly - since Datasette opens the underling SQLite database in read-only mode and enforces a one second time limit on queries, it’s safe to allow users to provide arbitrary SQL select queries for Datasette to execute. There’s a lot going on here! Let’s break the SQL down line-by-line: select snippet(articles_fts, -1, 'b4de2a49c8', '8c94a2ed4b', '...', 100) as snippet, We’re using snippet(), a built-in SQLite function, to generate a snippet highlighting the words that matched the query. We use two unique strings that I made up to mark the beginning and end of each match - you’ll see why in the JavaScript later on. articles_fts.rank, articles.title, articles.url, articles.author, articles.year These are the other fields we need back - most of them are from the articles table but we retrieve the rank (representing the strength of the search match) from the magical articles_fts table. from articles join articles_fts on articles.rowid = articles_fts.rowid articles is the table containing our data. articles_fts is a magic SQLite virtual table which implements full-text search - we need to join against it to be able to query it. where articles_fts match :search || ""*"" order by rank limit 10; :search || ""*"" takes the ?search= argument from the page querystring and adds a * to the end of it, giving us the wildcard search that we want for autocomplete. We then match that against the articles_fts table using the match operator. Finally, we order by rank so that the best matching results are returned at the top - and limit to the first 10 results. How do we turn this into an API? As before, the secret is to add the .json extension. Datasette actually supports multiple shapes of JSON - we’re going to use ?_shape=array to get back a plain array of objects: JSON API call to search for articles matching SVG The HTML version of that page shows the time taken to execute the SQL in the footer. Hitting refresh a few times, I get response times between 2 and 5ms - easily fast enough to power a responsive autocomplete feature. A simple JavaScript autocomplete search interface I considered building this using React or Svelte or another of the myriad of JavaScript framework options available today, but then I remembered that vanilla JavaScript in 2018 is a very productive environment all on its own. We need a few small utility functions: first, a classic debounce function adapted from this one by David Walsh: function debounce(func, wait, immediate) { let timeout; return function() { let context = this, args = arguments; let later = () => { timeout = null; if (!immediate) func.apply(context, args); }; let callNow = immediate && !timeout; clearTimeout(timeout); timeout = setTimeout(later, wait); if (callNow) func.apply(context, args); }; }; We’ll use this to only send fetch() requests a maximum of once every 100ms while the user is typing. Since we’re rendering data that might include HTML tags (24 ways is a site about web development after all), we need an HTML escaping function. I’m amazed that browsers still don’t bundle a default one of these: const htmlEscape = (s) => s.replace( />/g, '>' ).replace( /Autocomplete search

And now the autocomplete implementation itself, as a glorious, messy stream-of-consciousness of JavaScript: // Embed the SQL query in a multi-line backtick string: const sql = `select snippet(articles_fts, -1, 'b4de2a49c8', '8c94a2ed4b', '...', 100) as snippet, articles_fts.rank, articles.title, articles.url, articles.author, articles.year from articles join articles_fts on articles.rowid = articles_fts.rowid where articles_fts match :search || ""*"" order by rank limit 10`; // Grab a reference to the const searchbox = document.getElementById(""searchbox""); // Used to avoid race-conditions: let requestInFlight = null; searchbox.onkeyup = debounce(() => { const q = searchbox.value; // Construct the API URL, using encodeURIComponent() for the parameters const url = ( ""https://search-24ways.herokuapp.com/24ways-866073b.json?sql="" + encodeURIComponent(sql) + `&search=${encodeURIComponent(q)}&_shape=array` ); // Unique object used just for race-condition comparison let currentRequest = {}; requestInFlight = currentRequest; fetch(url).then(r => r.json()).then(d => { if (requestInFlight !== currentRequest) { // Avoid race conditions where a slow request returns // after a faster one. return; } let results = d.map(r => `

${htmlEscape(r.title)}

${htmlEscape(r.author)} - ${r.year}

${highlight(r.snippet)}

`).join(""""); document.getElementById(""results"").innerHTML = results; }); }, 100); // debounce every 100ms There’s just one more utility function, used to help construct the HTML results: const highlight = (s) => htmlEscape(s).replace( /b4de2a49c8/g, '' ).replace( /8c94a2ed4b/g, '' ); This is what those unique strings passed to the snippet() function were for. Avoiding race conditions in autocomplete One trick in this code that you may not have seen before is the way race-conditions are handled. Any time you build an autocomplete feature, you have to consider the following case: User types acces Browser sends request A - querying documents matching acces* User continues to type accessibility Browser sends request B - querying documents matching accessibility* Request B returns. It was fast, because there are fewer documents matching the full term The results interface updates with the documents from request B, matching accessibility* Request A returns results (this was the slower of the two requests) The results interface updates with the documents from request A - results matching access* This is a terrible user experience: the user saw their desired results for a brief second, and then had them snatched away and replaced with those results from earlier on. Thankfully there’s an easy way to avoid this. I set up a variable in the outer scope called requestInFlight, initially set to null. Any time I start a new fetch() request, I create a new currentRequest = {} object and assign it to the outer requestInFlight as well. When the fetch() completes, I use requestInFlight !== currentRequest to sanity check that the currentRequest object is strictly identical to the one that was in flight. If a new request has been triggered since we started the current request we can detect that and avoid updating the results. It’s not a lot of code, really And that’s the whole thing! The code is pretty ugly, but when the entire implementation clocks in at fewer than 70 lines of JavaScript, I honestly don’t think it matters. You’re welcome to refactor it as much you like. How good is this search implementation? I’ve been building search engines for a long time using a wide variety of technologies and I’m happy to report that using SQLite in this way is genuinely a really solid option. It scales happily up to hundreds of MBs (or even GBs) of data, and the fact that it’s based on SQL makes it easy and flexible to work with. A surprisingly large number of desktop and mobile applications you use every day implement their search feature on top of SQLite. More importantly though, I hope that this demonstrates that using Datasette for an API means you can build relatively sophisticated API-backed applications with very little backend programming effort. If you’re working with a small-to-medium amount of data that changes infrequently, you may not need a more expensive database. Datasette-powered applications easily fit within the free tier of both Heroku and Zeit Now. For more of my writing on Datasette, check out the datasette tag on my blog. And if you do build something fun with it, please let me know on Twitter.",2018,Simon Willison,simonwillison,2018-12-19T00:00:00+00:00,https://24ways.org/2018/fast-autocomplete-search-for-your-website/,code 209,Feeding the Audio Graph,"In 2004, I was given an iPod. I count this as one of the most intuitive pieces of technology I’ve ever owned. It wasn’t because of the the snazzy (colour!) menus or circular touchpad. I loved how smoothly it fitted into my life. I could plug in my headphones and listen to music while I was walking around town. Then when I got home, I could plug it into an amplifier and carry on listening there. There was no faff. It didn’t matter if I could find my favourite mix tape, or if my WiFi was flakey - it was all just there. Nowadays, when I’m trying to pair my phone with some Bluetooth speakers, or can’t find my USB-to-headphone jack, or even access any music because I don’t have cellular reception; I really miss this simplicity. The Web Audio API I think the Web Audio API feels kind of like my iPod did. It’s different from most browser APIs - rather than throwing around data, or updating DOM elements - you plug together a graph of audio nodes, which the browser uses to generate, process, and play sounds. The thing I like about it is that you can totally plug it into whatever you want, and it’ll mostly just work. So, let’s get started. First of all we want an audio source.