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Re: [Public WebGL] vertexAttribPointer conformance test



In particular, the check in this test is written as:

    if (st > 0 && st < bytesPerElement) {

(where bytesPerElement is bytesPerComponent * size); I think it should be:

    if (st > 0 && st % info.bytesPerComponent != 0) {

Which seems to give the desired results.. that is:

gl.vertexAttribPointer(0, 4, gl.SHORT, false, 2, 24) succeeds, but
gl.vertexAttribPointer(0, 4, gl.SHORT, false, 3, 24) fails because the stride is invalid (results in an unaligned access)

   - Vlad


----- Original Message -----
> I think some of these changes are wrong -- I agree that we should
> disallow (and I believe we already do and check for):
> 
> size = 3, type = FLOAT, stride = 2
> 
> but I do not think that we should disallow
> 
> size = 3, type = FLOAT, stride = 4
> 
> which the test currently does... the result here is perfectly valid,
> from my reading of the spec.
> 
> - Vlad
> 
> ----- Original Message -----
> > So I updated the test to test lots of combinations (checked in)
> >
> >
> > That brings up more questions about the restrictions added in
> > section
> > 6.3
> >
> >
> > 1st) "why the restrictions"
> >
> >
> >
> >
> > Is there some situation we are trying to prevent that we need to
> > prevent?
> >
> >
> > 2nd) "why not more restrictions"
> >
> >
> > As currently specified it's possible to set size = 4, type = byte,
> > stride = 1. So as input to the shader you'll get
> >
> >
> > vec4 (element0,element1,element2,element3)
> > vec4 (element1,element2,element3,element4)
> > vec4 (element2,element3,element4,element5)
> >
> >
> > ...
> >
> > 3rd) "why INVALID_OPERATION"
> >
> >
> >
> >
> > wouldn't INVALID_VALUE be more appropriate?
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