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-rw-r--r--mesalib/src/mesa/tnl/t_vb_cull.c97
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
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+++ 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 */
+};