Name EXT_blend_logic_op Name Strings GL_EXT_blend_logic_op Version $Date: 1995/03/31 04:40:24 $ $Revision: 1.4 $ Number 39 Dependencies EXT_blend_minmax affects the definition of this extension Overview A single additional blending equation is specified using the interface defined by EXT_blend_minmax. This equation is a simple logical combination of the source and destination colors, where the specific logical operation is as specified by LogicOp. While only the XOR operation may find wide application, the generality of full logical operations is allowed. New Procedures and Functions None New Tokens None Additions to Chapter 2 of the GL Specification (OpenGL Operation) None Additions to Chapter 3 of the GL Specification (Rasterization) None Additions to Chapter 4 of the GL Specification (Per-Fragment Operations and the Framebuffer) A single additional blending equation is defined. If BlendEquationEXT is called with set to LOGIC_OP, the blending equation becomes C = Cs OP Cd where Cs and Cd are the source and destination colors, and OP is the logic operation as specified by LogicOp. The value of boolean parameter LOGIC_OP (specified by Enable and Disable, and queried with IsEnabled) has no affect on blending, even when the blend equation is specified as LOGIC_OP. Additions to Chapter 5 of the GL Specification (Special Functions) None Additions to Chapter 6 of the GL Specification (State and State Requests) None Additions to the GLX Specification None GLX Protocol None Dependencies on EXT_blend_minmax If this extension is supported, but EXT_blend_minmax is not, then this extension effectively adds the procedure BlendEquationEXT, its parameter FUNC_ADD_EXT, and the query target BLEND_EQUATION_EXT, as described in EXT_blend_minmax. It is therefore as though EXT_blend_minmax were also supported, except that equations MIN_EXT and MAX_EXT are not supported. Errors INVALID_ENUM is generated by BlendEquationEXT if its single parameter is not FUNC_ADD_EXT, MIN_EXT, MAX_EXT, FUNC_SUBTRACT_EXT, FUNC_REVERSE_SUBTRACT_EXT, or LOGIC_OP. INVALID_OPERATION is generated if BlendEquationEXT is executed between the execution of Begin and the corresponding execution to End. New State Get Value Get Command Type Initial Value Attribute --------- ----------- ---- ------------- --------- BLEND_EQUATION_EXT GetIntegerv Z6 FUNC_ADD_EXT color-buffer New Implementation Dependent State None