vbo: fix offset in minmax cache key

Instead of saving primitive offset in the minmax cache key,
save the actual buffer offset which is used in the cache lookup.

Fixes rendering artifact seen with GoogleEarth when run with
VMware driver.

v2: Per Brian's comment, initialize offset to avoid compiler warning.

Cc: mesa-stable@lists.freedesktop.org
Reviewed-by: Brian Paul <brianp@vmware.com>

diff --git a/src/mesa/vbo/vbo_minmax_index.c b/src/mesa/vbo/vbo_minmax_index.c
index 4c17a08..58a2af4 100644 (file)
--- a/src/mesa/vbo/vbo_minmax_index.c
+++ b/src/mesa/vbo/vbo_minmax_index.c
@@ -245,6 +245,7 @@ vbo_get_minmax_index(struct gl_context *ctx,
       _mesa_primitive_restart_index(ctx, ib->index_size);
    const char *indices;
    GLuint i;
+   GLintptr offset = 0;
 
    indices = (char *) ib->ptr + prim->start * ib->index_size;
    if (_mesa_is_bufferobj(ib->obj)) {
@@ -254,7 +255,8 @@ vbo_get_minmax_index(struct gl_context *ctx,
                                 count, min_index, max_index))
          return;
 
-      indices = ctx->Driver.MapBufferRange(ctx, (GLintptr) indices, size,
+      offset = indices;
+      indices = ctx->Driver.MapBufferRange(ctx, offset, size,
                                            GL_MAP_READ_BIT, ib->obj,
                                            MAP_INTERNAL);
    }
@@ -337,8 +339,8 @@ vbo_get_minmax_index(struct gl_context *ctx,
    }
 
    if (_mesa_is_bufferobj(ib->obj)) {
-      vbo_minmax_cache_store(ctx, ib->obj, ib->index_size, prim->start, count,
-                             *min_index, *max_index);
+      vbo_minmax_cache_store(ctx, ib->obj, ib->index_size, offset,
+                             count, *min_index, *max_index);
       ctx->Driver.UnmapBuffer(ctx, ib->obj, MAP_INTERNAL);
    }
 }