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Re: [Public WebGL] Move flipY and asPremultipliedAlpha parameters out of DOM helpers
On 20/05/2010 10:45, Kenneth Russell wrote:
OpenGL ES 2.0 eliminated the GL_GENERATE_MIPMAP texture
parameter, replacing it with the explicit glGenerateMipmap, presumably
because of ill defined semantics.
No. It was removed from OpenGL ES because it is a second way of
accomplishing generation of mipmaps. It was subsequentl removed from
Open GL 3.2 for much the same reason.
The semantic was clear. The older spec. said "If the value of texture
parameter GENERATE MIPMAP is TRUE, and a change is made to the
interior or border texels of the level base array of a mipmap by
one of the texture image specification operations ... a complete
set of mipmap arrays ... will be computed." As the portions I have
highlighted clearly state, no mipmaps will be generated until a change
is made by, e.g., TexImage2D. Merely setting the parameter does nothing.
Cedric's proposed semantic does indeed have precedent.
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