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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.

Regards

    -Mark

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