TEXTURE_NPOT - Non power of two
textures are supported by the hardware.
TEXTURE_NPOT_BASIC - The
hardware supports non power of two textures, but you also need to check the
cogl_feature_texture_npot_mipmap and cogl_feature_texture_npot_repeat features to know if
the hardware supports npot texture mipmaps or repeat modes other than cogl_pipeline_wrap_mode_clamp_to_edge
respectively.
TEXTURE_NPOT_MIPMAP -
Mipmapping is supported in conjuntion with non power of two textures.
TEXTURE_NPOT_REPEAT - Repeat
modes other than cogl_pipeline_wrap_mode_clamp_to_edge are supported by the hardware.