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-rw-r--r--mesalib/src/mesa/tnl/t_vb_points.c114
1 files changed, 114 insertions, 0 deletions
diff --git a/mesalib/src/mesa/tnl/t_vb_points.c b/mesalib/src/mesa/tnl/t_vb_points.c
new file mode 100644
index 000000000..a52505b4b
--- /dev/null
+++ b/mesalib/src/mesa/tnl/t_vb_points.c
@@ -0,0 +1,114 @@
+/*
+ * Mesa 3-D graphics library
+ * Version: 7.0
+ *
+ * Copyright (C) 1999-2007 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:
+ * Brian Paul
+ */
+
+#include "main/glheader.h"
+#include "main/mtypes.h"
+#include "main/dd.h"
+#include "main/imports.h"
+#include "t_context.h"
+#include "t_pipeline.h"
+
+
+struct point_stage_data {
+ GLvector4f PointSize;
+};
+
+#define POINT_STAGE_DATA(stage) ((struct point_stage_data *)stage->privatePtr)
+
+
+/**
+ * Compute point size for each vertex from the vertex eye-space Z
+ * coordinate and the point size attenuation factors.
+ * Only done when point size attenuation is enabled and vertex program is
+ * disabled.
+ */
+static GLboolean
+run_point_stage(GLcontext *ctx, struct tnl_pipeline_stage *stage)
+{
+ if (ctx->Point._Attenuated && !ctx->VertexProgram._Current) {
+ struct point_stage_data *store = POINT_STAGE_DATA(stage);
+ struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
+ const GLfloat *eyeCoord = (GLfloat *) VB->EyePtr->data + 2;
+ const GLint eyeCoordStride = VB->EyePtr->stride / sizeof(GLfloat);
+ const GLfloat p0 = ctx->Point.Params[0];
+ const GLfloat p1 = ctx->Point.Params[1];
+ const GLfloat p2 = ctx->Point.Params[2];
+ const GLfloat pointSize = ctx->Point.Size;
+ GLfloat (*size)[4] = store->PointSize.data;
+ GLuint i;
+
+ for (i = 0; i < VB->Count; i++) {
+ const GLfloat dist = FABSF(*eyeCoord);
+ const GLfloat q = p0 + dist * (p1 + dist * p2);
+ const GLfloat atten = (q != 0.0) ? SQRTF(1.0 / q) : 1.0;
+ size[i][0] = pointSize * atten; /* clamping done in rasterization */
+ eyeCoord += eyeCoordStride;
+ }
+
+ VB->AttribPtr[_TNL_ATTRIB_POINTSIZE] = &store->PointSize;
+ }
+
+ return GL_TRUE;
+}
+
+
+static GLboolean
+alloc_point_data(GLcontext *ctx, struct tnl_pipeline_stage *stage)
+{
+ struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
+ struct point_stage_data *store;
+ stage->privatePtr = _mesa_malloc(sizeof(*store));
+ store = POINT_STAGE_DATA(stage);
+ if (!store)
+ return GL_FALSE;
+
+ _mesa_vector4f_alloc( &store->PointSize, 0, VB->Size, 32 );
+ return GL_TRUE;
+}
+
+
+static void
+free_point_data(struct tnl_pipeline_stage *stage)
+{
+ struct point_stage_data *store = POINT_STAGE_DATA(stage);
+ if (store) {
+ _mesa_vector4f_free( &store->PointSize );
+ _mesa_free( store );
+ stage->privatePtr = NULL;
+ }
+}
+
+
+const struct tnl_pipeline_stage _tnl_point_attenuation_stage =
+{
+ "point size attenuation", /* name */
+ NULL, /* stage private data */
+ alloc_point_data, /* alloc data */
+ free_point_data, /* destructor */
+ NULL,
+ run_point_stage /* run */
+};