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Forget about Web standards and go way beyond the usual capabilities of Web scripting languages. Learn how to create stunning effects using canvas/svg/vml, how to control animated graphics in JavaScript, and how to merge all kinds of standards and technologies to create a whole new world of possibilities. Using Paul\'s latest project as an example, he shows you how to adapt the things he talks about into new projects, featuring his new JavaScript game engine. Paul demonstrates how to control animated graphics in the browser, how to scale and rotate elements smoothly, and how to combine canvas, svg and filters with CSS to adapt new standards in browsers that don\'t support them. See how to move physics from the real world to the Web browser.
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Beyond the standards
Advanced Animation and Physics in JavaScript
Beyond the standards
Advanced Animation and Physics in JavaScript
Beyond the standards
Pushing the web beyond its limits
Web Standards
+ Great theory
+ The way it should be
- Minor progress for 10 years- Very difficult to push across parties
Okay then,let‘s wait until
something changes.
No way!Let‘s push the
web!
Walk.How to create a walking character
1. The Basics
• Center or not?
• Click angles - How many possible directions?
• Preparing the images
2. The animation(s)
• Animate the character by changing the image
• Move the character
3. Tweak
• Walk in constant speed
• Easing
• Multiple clicks handling
Scroll.How to create a scrollable, isometric
world
But that‘s not possible!
• Isometry needs skewed, non-retangle elements
• HTML doesn‘ t have them
Don‘t think about limits
• So you cannot use events that „bleed through“ elements?
• Sure you can!
• Build your own event structure in JavaScript
Don‘t limit yourself to a given standard - you can always build your own with JavaScript.
There‘s one fundamental thing you need to know..
Knowledge is power
New standardsCanvas, CSS Transforms
Canvas
• Feels like a true HMTL element
• Easy JavaScript API
• Safari, Firefox, Opera
• ..IE support using ExCanvas
Get your hands dirty!
CSS Transforms
• Webkit-only (Safari, iPhone, Android, Air)
• 2D transformations on HTML elements
• Yes, all kinds of 2d transformations: Rotating, Scaling, Skewing
Example: Coverflow
...wouldn‘t it be cool to have CSS transforms in
other browsers?
..omg, IE already has!
Transformie
• Parses stylesheets and inline styles, tracks them using IE only onpropertychange
• Creates a custom matrix for every function (rotate, scale, skew)
• Multiplies all matrices
• Creates the IE matrix filter on the element
..but what about the rest?
CSS Transforms in other browsers
• Firefox (< 3.1)/Opera has no CSS transforms
• What can we do? Push the web!
• Two possible methods
• Rerender elements to canvas and modify them
• Insert elements into SVG and use its transform features
The Canvas approach
• Find all instances of -webkit-transform
• For every found element:
• Create a new <canvas> element at the exact same position as the original, with the same constrains
• Rotate/Modify/Translate the whole canvas by the values found in the transform functions
• Literally draw borders, background and text for the original item into the canvas and for all sub items
• Recompute the new constrains of the element
Example: Canvas
The SVG approach
• Find all instances of -webkit-transform
• For every found element:
• Serialize the whole node (outerHTML) into a string (without positioning data in the style attribute)
• Wrap it around a prepared SVG XML Header
• Also insert the transform value as <g transform=‘...‘>
• Encode the whole string to base64
• Create a new embed element with the base64 string as data source, and render it to the page
Example: SVG
Pushing the standardsHow library developers help
defining standards
How a library dev smoothens the path before web standards jump in
• The Copy approach
• Replicate an existing standard on other platforms with the help of different technologies
• Example: Excanvas
• The „Lowest common multiple“ approach
• Take a couple of different standards across browsers and create a subset that can be used across browsers
• Example: Dojox GFX
Using the LCM approach, we can help define new standards.
..since we are the ones that try to find a suitable subset for the end-developer
Now everyone!Let‘s push the
web!
Question?
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