GL_EXT_texture_filter_anisotropic
http://www.opengl.org/registry/specs/EXT/texture_filter_anisotropic.txt
GL_EXT_texture_filter_anisotropic
	GL_TEXTURE_MAX_ANISOTROPY_EXT 0x84FE
	GL_MAX_TEXTURE_MAX_ANISOTROPY_EXT 0x84FF
