1991-2006 Silicon Graphics, Inc. glStencilMaskSeparate 3G glStencilMaskSeparate control the front and/or back writing of individual bits in the stencil planes void glStencilMaskSeparate GLenum face GLuint mask face Specifies whether the front and/or back stencil writemask is updated. Three symbolic constants are valid: GL_FRONT, GL_BACK, and GL_FRONT_AND_BACK. mask Specifies a bit mask to enable and disable writing of individual bits in the stencil planes. Initially, the mask is all 1's. glStencilMaskSeparate controls the writing of individual bits in the stencil planes. The least significant n bits of mask, where n is the number of bits in the stencil buffer, specify a mask. Where a 1 appears in the mask, it's possible to write to the corresponding bit in the stencil buffer. Where a 0 appears, the corresponding bit is write-protected. Initially, all bits are enabled for writing. There can be two separate mask writemasks; one affects back-facing polygons, and the other affects front-facing polygons as well as other non-polygon primitives. glStencilMask sets both front and back stencil writemasks to the same values, as if glStencilMaskSeparate were called with face set to GL_FRONT_AND_BACK. glStencilMaskSeparate is available only if the GL version is 2.0 or greater. GL_INVALID_OPERATION is generated if glStencilMaskSeparate is executed between the execution of glBegin and the corresponding execution of glEnd. glGet with argument GL_STENCIL_WRITEMASK, GL_STENCIL_BACK_WRITEMASK, or GL_STENCIL_BITS glColorMask, glDepthMask, glIndexMask, glStencilFunc, glStencilFuncSeparate, glStencilMask, glStencilOp, glStencilOpSeparate Copyright 2006 Khronos Group. This material may be distributed subject to the terms and conditions set forth in the Open Publication License, v 1.0, 8 June 1999. http://opencontent.org/openpub/.