diff options
Diffstat (limited to 'mesalib/src/mesa/tnl/t_vb_cull.c')
-rw-r--r-- | mesalib/src/mesa/tnl/t_vb_cull.c | 97 |
1 files changed, 97 insertions, 0 deletions
diff --git a/mesalib/src/mesa/tnl/t_vb_cull.c b/mesalib/src/mesa/tnl/t_vb_cull.c new file mode 100644 index 000000000..712901acf --- /dev/null +++ b/mesalib/src/mesa/tnl/t_vb_cull.c @@ -0,0 +1,97 @@ +/* + * 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 "main/glheader.h" +#include "main/colormac.h" +#include "main/context.h" +#include "main/macros.h" +#include "main/imports.h" +#include "main/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->AttribPtr[_TNL_ATTRIB_NORMAL]->data; + GLuint stride = VB->AttribPtr[_TNL_ATTRIB_NORMAL]->stride; + GLuint count = VB->Count; + GLuint i; + + if (ctx->VertexProgram._Current || + !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 */ +}; |