Creating and using my own mipmap of a texture atlas

I'm currently using the automatic mipmap generation (C# + OpenTK):

GL.GenerateMipmap(GenerateMipmapTarget.Texture2D);

The texture I'm using is tiled into blocks of 16px². So my questions would be:

• Is it possible to use a mipmap which doesn't get downsized to 1x1?
• What would be the best way to create a mipmap which doesn't "blur开发者_Go百科" the blocks into another?

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You mean, using a mipmap chain that doesn't get up to 1x1? You can limit which levels can be used with glTexParameter, see the GL_TEXTURE_MIN_LOD, GL_TEXTURE_MAX_LOD, GL_TEXTURE_BASE_LEVEL and GL_TEXTURE_MAX_LEVEL parameters.

I don't understand your second question, if you mean using your own generated mipmaps, see the level parameter of glTexImage2D, with it you can upload your own mipmaps, filtered in any way.