RE: [css3-animations][css3-transitions][css3-background] Animating box-shadow

Some thoughts after rereading Brad's description a 3rd time...

a. The transition should be fluid, not integral stepped.  Brad's description doesn't say otherwise but it's easy to read too much into the "1px" reference in step 5.
b. It vastly simplifies the problem space to think of inner spreads as equivalent to negative outer spreads.  Similarly for offsets.
c. Incorporating 'b', the algorithm gets much simpler to describe mathematically as each property transitions along a single axis linearly without backtracking.
d. Normalizing across fields (offsets, spreads) so that they transition at the same rate is definitely important.
e. WG must decide whether they want "cross-inset" transitions to be evenly split between inset and outset renderings or not.  I suggest "not".  The math is simpler and the rendering is more flexible.  If people want a half-inset, half-outset rendering it's easy to do that with an animation that has an additional middle state of "0 0 0 0 transparent".
f. Color transitions with rgba.  Premultiplied?  Non-premultiplied?  One or the other depending on another property?

Despite the complexity suggested above, I definitely concur it's worth supporting (and documenting) rather than forcing people to do it with JS.

Received on Tuesday, 1 November 2011 23:02:32 UTC