jQuery 1.4 Animation Techniques - Index of

CSS3 Animations
}
el.filters.item("DXImageTransform.Microsoft.Matrix")
.M12 = -sin;
el.filters.item("DXImageTransform.Microsoft.Matrix")
.M21 = sin;
el.filters.item("DXImageTransform.Microsoft.Matrix")
.M22 = cos;
} else {
img.css(vendor, rotateStrings.join(""));
}
setInterval(function() { doRotate() }, 100);
4. Save the page as rotate.html. If we run the page in a browser now, we should see
the color wheel slowly spinning around its center.
What just happened?
The first thing we do is cache a selector for the image as we'll be referring to it several times
throughout the code. Note that this is the only jQuery object we create in the whole script,
which as we've discussed earlier in the book, is great for improving performance.
We also set some other variables at this point including the offset of the image
(its absolute position on the page), its original width and height, and an array
containing different parts of the CSS property that we'll set, in string and integer formats.
We also set an inline function (getVendor()) as the value of a variable which we can use
to determine which vendor prefix to use. This function first also sets some variables which
will be used to store the determined vendor prefix, and an object literal containing all of
the different prefixes we want to test for. We also include the native transform property.
Although this isn't yet supported by any browser, one day it may be, so this helps futureproof
our code.
The function iterates over each property in the object literal using a for in loop. Within
the loop, we try to read the value of the transform property using each vendor prefix. An
interesting fact is that each browser will report none as the value of the prefix it supports,
and a falsey value such as false, null, or undefined for the prefixes it doesn't support.
We can use this to reliably determine which browser is in use and therefore which vendor
prefix we need to use. The correct vendor prefix for whichever browser is in use is then
saved to the vendor variable ready to be returned.
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