GL_ATI_separate_stencil http://www.opengl.org/registry/specs/ATI/separate_stencil.txt GL_ATI_separate_stencil GL_STENCIL_BACK_FUNC_ATI 0x8800 GL_STENCIL_BACK_FAIL_ATI 0x8801 GL_STENCIL_BACK_PASS_DEPTH_FAIL_ATI 0x8802 GL_STENCIL_BACK_PASS_DEPTH_PASS_ATI 0x8803 void glStencilOpSeparateATI (GLenum face, GLenum sfail, GLenum dpfail, GLenum dppass) void glStencilFuncSeparateATI (GLenum frontfunc, GLenum backfunc, GLint ref, GLuint mask)