/* * Mesa 3-D graphics library * Version: 6.5 * * Copyright (C) 1999-2006 Brian Paul All Rights Reserved. * * Permission is hereby granted, free of charge, to any person obtaining a * copy of this software and associated documentation files (the "Software"), * to deal in the Software without restriction, including without limitation * the rights to use, copy, modify, merge, publish, distribute, sublicense, * and/or sell copies of the Software, and to permit persons to whom the * Software is furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included * in all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. * * Authors: * Keith Whitwell <keith@tungstengraphics.com> */ #include "glheader.h" #include "colormac.h" #include "context.h" #include "macros.h" #include "imports.h" #include "mtypes.h" #include "math/m_xform.h" #include "t_context.h" #include "t_pipeline.h" /* EXT_vertex_cull. Not really a big win, but probably depends on * your application. This stage not included in the default pipeline. */ static GLboolean run_cull_stage( GLcontext *ctx, struct tnl_pipeline_stage *stage ) { TNLcontext *tnl = TNL_CONTEXT(ctx); struct vertex_buffer *VB = &tnl->vb; const GLfloat a = ctx->Transform.CullObjPos[0]; const GLfloat b = ctx->Transform.CullObjPos[1]; const GLfloat c = ctx->Transform.CullObjPos[2]; GLfloat *norm = (GLfloat *)VB->NormalPtr->data; GLuint stride = VB->NormalPtr->stride; GLuint count = VB->Count; GLuint i; if (ctx->ShaderObjects._VertexShaderPresent) return GL_TRUE; if (ctx->VertexProgram._Enabled || !ctx->Transform.CullVertexFlag) return GL_TRUE; VB->ClipOrMask &= ~CLIP_CULL_BIT; VB->ClipAndMask |= CLIP_CULL_BIT; for (i = 0 ; i < count ; i++) { GLfloat dp = (norm[0] * a + norm[1] * b + norm[2] * c); if (dp < 0) { VB->ClipMask[i] |= CLIP_CULL_BIT; VB->ClipOrMask |= CLIP_CULL_BIT; } else { VB->ClipMask[i] &= ~CLIP_CULL_BIT; VB->ClipAndMask &= ~CLIP_CULL_BIT; } STRIDE_F(norm, stride); } return !(VB->ClipAndMask & CLIP_CULL_BIT); } const struct tnl_pipeline_stage _tnl_vertex_cull_stage = { "EXT_cull_vertex", NULL, /* private data */ NULL, /* ctr */ NULL, /* destructor */ NULL, run_cull_stage /* run -- initially set to init */ };