Possible issue regarding some enums and constants

[Francesco Bertolaccini]

According to the specifications, glTexParameter should accept TextureTarget as the first argument and a TextureParameter as the second, for example GL_TEXTURE_MAX_LEVEL.

However, in OpenGL.NET both GL_TEXTURE_MAX_LEVEL and GL_TEXTURE_2D belong to the TextureTarget enum, making it impossible to set some parameters.

This may be a problem with the code generation system so other constants might be affected as well.

Example code:

// Standard C code
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, mipMapCount);

// Expected C# code
Gl.TexParameterI(TextureTarget.Texture2d, TextureParameter.TextureMaxLevel, mipMapCount); // TextureParameter doesn't contain the member TextureMaxLevel

[Luca Piccioni]

Sadly, the code generator is fine; the cause of the problem is related directly with the XML specification offered by Khronos. I got quite a few problem about it, and the code generator is able to add missing enumeration using its configuration files.

Currently my workaround is a simple cast:

Gl.TexParameter(TextureTarget, (TextureParameterName)Gl.TEXTURE_MAX_LEVEL, _MipmapMaxLevel);

or using the other overload

Gl.TexParameter((int)TextureTarget, Gl.TEXTURE_MAX_LEVEL, _MipmapMaxLevel);

but this misses the point of having the enumerations.

....

Indeed I can easily add missing TextureParameterName enumeration value, but sadly TextureTarget has some wrong enumerants. This is the current Khronos definition:

<group name="TextureTarget">
        <enum name="GL_DETAIL_TEXTURE_2D_SGIS"/>
        <enum name="GL_PROXY_TEXTURE_1D"/>
        <enum name="GL_PROXY_TEXTURE_1D_EXT"/>
        <enum name="GL_PROXY_TEXTURE_2D"/>
        <enum name="GL_PROXY_TEXTURE_2D_EXT"/>
        <enum name="GL_PROXY_TEXTURE_3D"/>
        <enum name="GL_PROXY_TEXTURE_3D_EXT"/>
        <enum name="GL_PROXY_TEXTURE_4D_SGIS"/>
        <enum name="GL_TEXTURE_1D"/>
        <enum name="GL_TEXTURE_2D"/>
        <enum name="GL_TEXTURE_3D"/>
        <enum name="GL_TEXTURE_3D_EXT"/>
        <enum name="GL_TEXTURE_3D_OES"/>
        <enum name="GL_TEXTURE_4D_SGIS"/>
        <enum name="GL_TEXTURE_BASE_LEVEL"/>
        <enum name="GL_TEXTURE_BASE_LEVEL_SGIS"/>
        <enum name="GL_TEXTURE_MAX_LEVEL"/>
        <enum name="GL_TEXTURE_MAX_LEVEL_SGIS"/>
        <enum name="GL_TEXTURE_MAX_LOD"/>
        <enum name="GL_TEXTURE_MAX_LOD_SGIS"/>
        <enum name="GL_TEXTURE_MIN_LOD"/>
        <enum name="GL_TEXTURE_MIN_LOD_SGIS"/>
    </group>

Probably this issue should be forwarded to Khronos bug tracking system. In the meanwhile, I'll check those two enumerations (again 😄)

[Francesco Bertolaccini]

Thanks for the prompt response, I am doing some research on the OpenGL Registry and this looks to be the place to report issues with the API specs: https://github.com/KhronosGroup/OpenGL-API

It's pretty barren, but I shall try and file an issue anyways...

[Luca Piccioni]

I think the correct bug tracking system is https://www.khronos.org/bugzilla/.

[Francesco Bertolaccini]

The relevant section seems to be closed to new bug submissions, pointing at the Github repository instead...