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-rw-r--r--mesalib/src/mesa/vbo/vbo_split.c161
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diff --git a/mesalib/src/mesa/vbo/vbo_split.c b/mesalib/src/mesa/vbo/vbo_split.c
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+
+/*
+ * 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>
+ */
+
+/* Deal with hardware and/or swtnl maximums:
+ * - maximum number of vertices in buffer
+ * - maximum number of elements (maybe zero)
+ *
+ * The maximums may vary with opengl state (eg if a larger hardware
+ * vertex is required in this state, the maximum number of vertices
+ * may be smaller than in another state).
+ *
+ * We want buffer splitting to be a convenience function for the code
+ * actually drawing the primitives rather than a system-wide maximum,
+ * otherwise it is hard to avoid pessimism.
+ *
+ * For instance, if a driver has no hardware limits on vertex buffer
+ * dimensions, it would not ordinarily want to split vbos. But if
+ * there is an unexpected fallback, eg memory manager fails to upload
+ * textures, it will want to pass the drawing commands onto swtnl,
+ * which does have limitations. A convenience function allows swtnl
+ * to split the drawing and vbos internally without imposing its
+ * limitations on drivers which want to use it as a fallback path.
+ */
+
+#include "main/glheader.h"
+#include "main/imports.h"
+#include "main/mtypes.h"
+
+#include "vbo_split.h"
+#include "vbo.h"
+
+/* True if a primitive can be split without copying of vertices, false
+ * otherwise.
+ */
+GLboolean split_prim_inplace(GLenum mode, GLuint *first, GLuint *incr)
+{
+ switch (mode) {
+ case GL_POINTS:
+ *first = 1;
+ *incr = 1;
+ return GL_TRUE;
+ case GL_LINES:
+ *first = 2;
+ *incr = 2;
+ return GL_TRUE;
+ case GL_LINE_STRIP:
+ *first = 2;
+ *incr = 1;
+ return GL_TRUE;
+ case GL_TRIANGLES:
+ *first = 3;
+ *incr = 3;
+ return GL_TRUE;
+ case GL_TRIANGLE_STRIP:
+ *first = 3;
+ *incr = 1;
+ return GL_TRUE;
+ case GL_QUADS:
+ *first = 4;
+ *incr = 4;
+ return GL_TRUE;
+ case GL_QUAD_STRIP:
+ *first = 4;
+ *incr = 2;
+ return GL_TRUE;
+ default:
+ *first = 0;
+ *incr = 1; /* so that count % incr works */
+ return GL_FALSE;
+ }
+}
+
+
+
+void vbo_split_prims( GLcontext *ctx,
+ const struct gl_client_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,
+ const struct split_limits *limits )
+{
+
+ if (ib) {
+ if (limits->max_indices == 0) {
+ /* Could traverse the indices, re-emitting vertices in turn.
+ * But it's hard to see why this case would be needed - for
+ * software tnl, it is better to convert to non-indexed
+ * rendering after transformation is complete, as is done in
+ * the t_dd_rendertmp.h templates. Are there any devices
+ * with hardware tnl that cannot do indexed rendering?
+ *
+ * For now, this path is disabled.
+ */
+ assert(0);
+ }
+ else if (max_index - min_index >= limits->max_verts) {
+ /* The vertex buffers are too large for hardware (or the
+ * swtnl module). Traverse the indices, re-emitting vertices
+ * in turn. Use a vertex cache to preserve some of the
+ * sharing from the original index list.
+ */
+ vbo_split_copy(ctx, arrays, prim, nr_prims, ib,
+ draw, limits );
+ }
+ else if (ib->count > limits->max_indices) {
+ /* The index buffer is too large for hardware. Try to split
+ * on whole-primitive boundaries, otherwise try to split the
+ * individual primitives.
+ */
+ vbo_split_inplace(ctx, arrays, prim, nr_prims, ib,
+ min_index, max_index, draw, limits );
+ }
+ else {
+ /* Why were we called? */
+ assert(0);
+ }
+ }
+ else {
+ if (max_index - min_index >= limits->max_verts) {
+ /* The vertex buffer is too large for hardware (or the swtnl
+ * module). Try to split on whole-primitive boundaries,
+ * otherwise try to split the individual primitives.
+ */
+ vbo_split_inplace(ctx, arrays, prim, nr_prims, ib,
+ min_index, max_index, draw, limits );
+ }
+ else {
+ /* Why were we called? */
+ assert(0);
+ }
+ }
+}
+