is there any reason why
#define GL_GENERATE_MIPMAP 0x8191
is missing in the GLES2 Linux Emulation SDK? I saw that it is included in the 1.1 SDK so I’m wondering why it is not there in GLES2.
GL_GENERATE_MIPMAP does not exist in OpenGL ES 2.0. You can use glGenerateMipmap() instead when you want to generate mipmaps.