--- /dev/null
+
+/*
+ * Mesa 3-D graphics library
+ *
+ * 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
+ * THE AUTHORS OR COPYRIGHT HOLDERS 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 <keithw@vmware.com>
+ */
+
+/* Helper for drivers which find themselves rendering a range of
+ * indices starting somewhere above zero. Typically the application
+ * is issuing multiple DrawArrays() or DrawElements() to draw
+ * successive primitives layed out linearly in the vertex arrays.
+ * Unless the vertex arrays are all in a VBO, the OpenGL semantics
+ * imply that we need to re-upload the vertex data on each draw call.
+ * In that case, we want to avoid starting the upload at zero, as it
+ * will mean every draw call uploads an increasing amount of not-used
+ * vertex data. Worse - in the software tnl module, all those
+ * vertices will be transformed and lit.
+ *
+ * If we just upload the new data, however, the indices will be
+ * incorrect as we tend to upload each set of vertex data to a new
+ * region.
+ *
+ * This file provides a helper to adjust the arrays, primitives and
+ * indices of a draw call so that it can be re-issued with a min_index
+ * of zero.
+ */
+
+#include <stdio.h>
+#include "main/glheader.h"
+#include "main/imports.h"
+#include "main/mtypes.h"
+
+#include "t_rebase.h"
+
+
+#define REBASE(TYPE) \
+static void *rebase_##TYPE( const void *ptr, \
+ GLuint count, \
+ TYPE min_index ) \
+{ \
+ GLuint i; \
+ const TYPE *in = (TYPE *)ptr; \
+ TYPE *tmp_indices = malloc(count * sizeof(TYPE)); \
+ \
+ if (tmp_indices == NULL) { \
+ _mesa_error_no_memory(__func__); \
+ return NULL; \
+ } \
+ \
+ for (i = 0; i < count; i++) \
+ tmp_indices[i] = in[i] - min_index; \
+ \
+ return (void *)tmp_indices; \
+}
+
+
+REBASE(GLuint)
+REBASE(GLushort)
+REBASE(GLubyte)
+
+
+
+/* Adjust primitives, indices and vertex definitions so that min_index
+ * becomes zero. There are lots of reasons for wanting to do this, eg:
+ *
+ * Software tnl:
+ * - any time min_index != 0, otherwise unused vertices lower than
+ * min_index will be transformed.
+ *
+ * Hardware tnl:
+ * - if ib != NULL and min_index != 0, otherwise vertices lower than
+ * min_index will be uploaded. Requires adjusting index values.
+ *
+ * - if ib == NULL and min_index != 0, just for convenience so this doesn't
+ * have to be handled within the driver.
+ *
+ * Hardware tnl with VBO support:
+ * - as above, but only when vertices are not (all?) in VBO's.
+ * - can't save time by trying to upload half a vbo - typically it is
+ * all or nothing.
+ */
+void t_rebase_prims( struct gl_context *ctx,
+ const struct gl_vertex_array *arrays[],
+ const struct _mesa_prim *prim,
+ GLuint nr_prims,
+ const struct _mesa_index_buffer *ib,
+ GLuint min_index,
+ GLuint max_index,
+ vbo_draw_func draw )
+{
+ struct gl_vertex_array tmp_arrays[VERT_ATTRIB_MAX];
+ const struct gl_vertex_array *tmp_array_pointers[VERT_ATTRIB_MAX];
+
+ struct _mesa_index_buffer tmp_ib;
+ struct _mesa_prim *tmp_prims = NULL;
+ const struct gl_vertex_array **saved_arrays = ctx->Array._DrawArrays;
+ void *tmp_indices = NULL;
+ GLuint i;
+
+ assert(min_index != 0);
+
+ if (0)
+ printf("%s %d..%d\n", __func__, min_index, max_index);
+
+
+ /* XXX this path is disabled for now.
+ * There's rendering corruption in some apps when it's enabled.
+ */
+ if (0 && ib && ctx->Extensions.ARB_draw_elements_base_vertex) {
+ /* If we can just tell the hardware or the TNL to interpret our
+ * indices with a different base, do so.
+ */
+ tmp_prims = malloc(sizeof(*prim) * nr_prims);
+
+ if (tmp_prims == NULL) {
+ _mesa_error_no_memory(__func__);
+ return;
+ }
+
+ for (i = 0; i < nr_prims; i++) {
+ tmp_prims[i] = prim[i];
+ tmp_prims[i].basevertex -= min_index;
+ }
+
+ prim = tmp_prims;
+ } else if (ib) {
+ /* Unfortunately need to adjust each index individually.
+ */
+ GLboolean map_ib = ib->obj->Name &&
+ !ib->obj->Mappings[MAP_INTERNAL].Pointer;
+ void *ptr;
+
+ if (map_ib)
+ ctx->Driver.MapBufferRange(ctx, 0, ib->obj->Size, GL_MAP_READ_BIT,
+ ib->obj, MAP_INTERNAL);
+
+
+ ptr = ADD_POINTERS(ib->obj->Mappings[MAP_INTERNAL].Pointer, ib->ptr);
+
+ /* Some users might prefer it if we translated elements to
+ * GLuints here. Others wouldn't...
+ */
+ switch (ib->index_size) {
+ case 4:
+ tmp_indices = rebase_GLuint( ptr, ib->count, min_index );
+ break;
+ case 2:
+ tmp_indices = rebase_GLushort( ptr, ib->count, min_index );
+ break;
+ case 1:
+ tmp_indices = rebase_GLubyte( ptr, ib->count, min_index );
+ break;
+ }
+
+ if (map_ib)
+ ctx->Driver.UnmapBuffer(ctx, ib->obj, MAP_INTERNAL);
+
+ if (tmp_indices == NULL) {
+ return;
+ }
+
+ tmp_ib.obj = ctx->Shared->NullBufferObj;
+ tmp_ib.ptr = tmp_indices;
+ tmp_ib.count = ib->count;
+ tmp_ib.index_size = ib->index_size;
+
+ ib = &tmp_ib;
+ }
+ else {
+ /* Otherwise the primitives need adjustment.
+ */
+ tmp_prims = malloc(sizeof(*prim) * nr_prims);
+
+ if (tmp_prims == NULL) {
+ _mesa_error_no_memory(__func__);
+ return;
+ }
+
+ for (i = 0; i < nr_prims; i++) {
+ /* If this fails, it could indicate an application error:
+ */
+ assert(prim[i].start >= min_index);
+
+ tmp_prims[i] = prim[i];
+ tmp_prims[i].start -= min_index;
+ }
+
+ prim = tmp_prims;
+ }
+
+ /* Just need to adjust the pointer values on each incoming array.
+ * This works for VBO and non-vbo rendering and shouldn't pesimize
+ * VBO-based upload schemes. However this may still not be a fast
+ * path for hardware tnl for VBO based rendering as most machines
+ * will be happier if you just specify a starting vertex value in
+ * each primitive.
+ *
+ * For drivers with hardware tnl, you only want to do this if you
+ * are forced to, eg non-VBO indexed rendering with start != 0.
+ */
+ for (i = 0; i < VERT_ATTRIB_MAX; i++) {
+ tmp_arrays[i] = *arrays[i];
+ tmp_arrays[i].Ptr += min_index * tmp_arrays[i].StrideB;
+ tmp_array_pointers[i] = &tmp_arrays[i];
+ }
+
+ /* Re-issue the draw call.
+ */
+ ctx->Array._DrawArrays = tmp_array_pointers;
+ ctx->NewDriverState |= ctx->DriverFlags.NewArray;
+
+ draw( ctx,
+ prim,
+ nr_prims,
+ ib,
+ GL_TRUE,
+ 0,
+ max_index - min_index,
+ NULL, 0, NULL );
+
+ ctx->Array._DrawArrays = saved_arrays;
+ ctx->NewDriverState |= ctx->DriverFlags.NewArray;
+
+ free(tmp_indices);
+
+ free(tmp_prims);
+}
+
+
+
projects / mesa.git / blobdiff