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authorRadosław Kujawa <radoslaw.kujawa@c0ff33.net>2026-07-17 14:54:32 +0200
committerRadosław Kujawa <radoslaw.kujawa@c0ff33.net>2026-07-17 14:54:32 +0200
commit2702c90d7a39fca2a3319c5e915fd290cb31fc70 (patch)
tree283c4d851efef7e3a7cd03ba80c87e2bffcdbb2c /src/mesa/tnl/t_vb_points.c
parent836167945ec2c7ad5acdf0aa17ce35ec1b9428a6 (diff)
Initial import.
Diffstat (limited to 'src/mesa/tnl/t_vb_points.c')
-rw-r--r--src/mesa/tnl/t_vb_points.c123
1 files changed, 123 insertions, 0 deletions
diff --git a/src/mesa/tnl/t_vb_points.c b/src/mesa/tnl/t_vb_points.c
new file mode 100644
index 0000000..746ea8b
--- /dev/null
+++ b/src/mesa/tnl/t_vb_points.c
@@ -0,0 +1,123 @@
+/*
+ * Mesa 3-D graphics library
+ * Version: 6.1
+ *
+ * Copyright (C) 1999-2004 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 "mtypes.h"
+#include "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 attenuated point sizes
+ */
+static GLboolean run_point_stage( GLcontext *ctx,
+ struct tnl_pipeline_stage *stage )
+{
+ struct point_stage_data *store = POINT_STAGE_DATA(stage);
+ struct vertex_buffer *VB = &TNL_CONTEXT(ctx)->vb;
+ const GLfloat (*eye)[4] = (const GLfloat (*)[4]) VB->EyePtr->data;
+ 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;
+
+ if (stage->changed_inputs) {
+ /* XXX do threshold and min/max clamping here? */
+ for (i = 0; i < VB->Count; i++) {
+ const GLfloat dist = -eye[i][2];
+ /* GLfloat dist = SQRTF(pos[0]*pos[0]+pos[1]*pos[1]+pos[2]*pos[2]);*/
+ size[i][0] = pointSize / (p0 + dist * (p1 + dist * p2));
+ }
+ }
+
+ VB->PointSizePtr = &store->PointSize;
+ VB->AttribPtr[_TNL_ATTRIB_POINTSIZE] = &store->PointSize;
+
+ return GL_TRUE;
+}
+
+
+/* If point size attenuation is on we'll compute the point size for
+ * each vertex in a special pipeline stage.
+ */
+static void check_point_size( GLcontext *ctx, struct tnl_pipeline_stage *d )
+{
+ d->active = ctx->Point._Attenuated && !ctx->VertexProgram._Enabled;
+}
+
+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 = MALLOC(sizeof(*store));
+ store = POINT_STAGE_DATA(stage);
+ if (!store)
+ return GL_FALSE;
+
+ _mesa_vector4f_alloc( &store->PointSize, 0, VB->Size, 32 );
+
+ /* Now run the stage.
+ */
+ stage->run = run_point_stage;
+ return stage->run( ctx, stage );
+}
+
+
+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 );
+ FREE( store );
+ stage->privatePtr = 0;
+ }
+}
+
+const struct tnl_pipeline_stage _tnl_point_attenuation_stage =
+{
+ "point size attenuation", /* name */
+ _NEW_POINT|_NEW_PROGRAM, /* check_state */
+ _NEW_POINT, /* run_state */
+ GL_FALSE, /* active */
+ _TNL_BIT_POS, /* inputs */
+ _TNL_BIT_POS, /* outputs */
+ 0, /* changed_inputs (temporary value) */
+ NULL, /* stage private data */
+ free_point_data, /* destructor */
+ check_point_size, /* check */
+ alloc_point_data /* run -- initially set to alloc data */
+};