[whatwg] Canvas pixel manipulation and performance
bzbarsky at MIT.EDU
Sun Nov 29 21:01:46 PST 2009
On 11/29/09 11:22 PM, Oliver Hunt wrote:
> I don't know where you're getting that idea from -- the clamping semantics for CanvasPixelArray and WebGLUnsignedByteArray are identical.
Perhaps Kenneth included the rounding behavior (which seems to be
WebCore/html/canvas/WebGLUnsignedByteArray.h) in "clamping semantics"?
CanvasPixelArray, which uses ByteArray, rounds to nearest integer (ties
rounded up), while WebGLUnsignedByteArray truncates.
Note that neither implements what the current spec draft calls for
(which is round-to-nearest, ties-to-even behavior). No opinion on
whether this _should_ be what the spec calls for.
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