glTexEnv

Specifies a texture environment. May be GL_TEXTURE_ENV , GL_TEXTURE_FILTER_CONTROL or GL_POINT_SPRITE .

Specifies the symbolic name of a single-valued texture environment parameter. May be either GL_TEXTURE_ENV_MODE , GL_TEXTURE_LOD_BIAS , GL_COMBINE_RGB , GL_COMBINE_ALPHA , GL_SRC0_RGB , GL_SRC1_RGB , GL_SRC2_RGB , GL_SRC0_ALPHA , GL_SRC1_ALPHA , GL_SRC2_ALPHA , GL_OPERAND0_RGB , GL_OPERAND1_RGB , GL_OPERAND2_RGB , GL_OPERAND0_ALPHA , GL_OPERAND1_ALPHA , GL_OPERAND2_ALPHA , GL_RGB_SCALE , GL_ALPHA_SCALE , or GL_COORD_REPLACE .

Specifies a single symbolic constant, one of GL_ADD , GL_ADD_SIGNED , GL_INTERPOLATE , GL_MODULATE , GL_DECAL , GL_BLEND , GL_REPLACE , GL_SUBTRACT , GL_COMBINE , GL_TEXTURE , GL_CONSTANT , GL_PRIMARY_COLOR , GL_PREVIOUS , GL_SRC_COLOR , GL_ONE_MINUS_SRC_COLOR , GL_SRC_ALPHA , GL_ONE_MINUS_SRC_ALPHA , a single boolean value for the point sprite texture coordinate replacement, a single floating-point value for the texture level-of-detail bias, or 1.0, 2.0, or 4.0 when specifying the GL_RGB_SCALE or GL_ALPHA_SCALE .