On 02/08/2012 06:08 AM, Kenneth Graunke wrote:
This failed to take basevertex into account:
If basevertex< 0:
(end + basevertex) might actually be in-bounds while 'end' is not.
We would have clamped in this case when we probably shouldn't.
This could break application drawing.
If basevertex> 0:
'end' might be in-bounds while (end + basevertex) might not.
We would have failed to clamp in this place. There's a comment
indicating the TNL module depends on max_index being in-bounds;
if so, it would likely break horribly.
Rather than trying to clamp correctly in the face of basevertex, simply
delete the clamping code and indicate that we don't have a valid range.
This causes _tnl_vbo_draw_prims to use vbo_get_minmax_indices() to
compute the actual bounds, which is much safer.
NOTE: This is a candidate for release branches.
Signed-off-by: Kenneth Graunke<kenn...@whitecape.org>
---
src/mesa/vbo/vbo_exec_array.c | 17 ++++++-----------
1 files changed, 6 insertions(+), 11 deletions(-)
diff --git a/src/mesa/vbo/vbo_exec_array.c b/src/mesa/vbo/vbo_exec_array.c
index c26a8cd..67073df 100644
--- a/src/mesa/vbo/vbo_exec_array.c
+++ b/src/mesa/vbo/vbo_exec_array.c
@@ -859,6 +859,7 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode,
GLint basevertex)
{
static GLuint warnCount = 0;
+ GLboolean index_bounds_valid = GL_TRUE;
GET_CURRENT_CONTEXT(ctx);
if (MESA_VERBOSE& VERBOSE_DRAW)
@@ -911,16 +912,6 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode,
end = MIN2(end, 0xffff);
}
- if (end>= ctx->Array.ArrayObj->_MaxElement) {
- /* Set 'end' to the max possible legal value */
- assert(ctx->Array.ArrayObj->_MaxElement>= 1);
- end = ctx->Array.ArrayObj->_MaxElement - 1;
-
- if (end< start) {
- return;
- }
- }
-
if (0) {
printf("glDraw[Range]Elements{,BaseVertex}"
"(start %u, end %u, type 0x%x, count %d) ElemBuf %u, "
@@ -930,13 +921,17 @@ vbo_exec_DrawRangeElementsBaseVertex(GLenum mode,
basevertex);
}
+ if ((int)(end + basevertex)< 0 ||
Again, maybe do this as:
if ((int) end + basevertex < 0 ||
+ end + basevertex>= ctx->Array.ArrayObj->_MaxElement)
+ index_bounds_valid = GL_FALSE;
+
#if 0
check_draw_elements_data(ctx, count, type, indices);
#else
(void) check_draw_elements_data;
#endif
- vbo_validated_drawrangeelements(ctx, mode, GL_TRUE, start, end,
+ vbo_validated_drawrangeelements(ctx, mode, index_bounds_valid, start, end,
count, type, indices, basevertex, 1);
}
Reviewed-by: Brian Paul <bri...@vmware.com>
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