vbo: introduce vbo_sizeof_ib_type() function

introduce vbo_sizeof_ib_type() function to return the index data type
size. I see some place use switch(ib->type) to get the index data type,
which is sort of duplicate.

Signed-off-by: Yuanhan Liu <[email protected]>
Reviewed-by: Brian Paul <[email protected]>
Reviewed-by: Eric Anholt <[email protected]>

2 files changed, 4 insertions, 28 deletions

diff --git a/src/mesa/state_tracker/st_draw.c b/src/mesa/state_tracker/st_draw.c
index 87a99786521..954f15a3437 100644
--- a/src/mesa/state_tracker/st_draw.c
+++ b/src/mesa/state_tracker/st_draw.c
@@ -584,20 +584,7 @@ setup_index_buffer(struct gl_context *ctx,
    if (ib) {
       struct gl_buffer_object *bufobj = ib->obj;
 
-      switch (ib->type) {
-      case GL_UNSIGNED_INT:
-         ibuffer->index_size = 4;
-         break;
-      case GL_UNSIGNED_SHORT:
-         ibuffer->index_size = 2;
-         break;
-      case GL_UNSIGNED_BYTE:
-         ibuffer->index_size = 1;
-         break;
-      default:
-         assert(0);
-	 return;
-      }
+      ibuffer->index_size = vbo_sizeof_ib_type(ib->type);
 
       /* get/create the index buffer object */
       if (_mesa_is_bufferobj(bufobj)) {
diff --git a/src/mesa/state_tracker/st_draw_feedback.c b/src/mesa/state_tracker/st_draw_feedback.c
index 4c1e67495b7..a99eb2bf7d5 100644
--- a/src/mesa/state_tracker/st_draw_feedback.c
+++ b/src/mesa/state_tracker/st_draw_feedback.c
@@ -218,20 +218,9 @@ st_feedback_draw_vbo(struct gl_context *ctx,
    if (ib) {
       struct gl_buffer_object *bufobj = ib->obj;
 
-      switch (ib->type) {
-      case GL_UNSIGNED_INT:
-         ibuffer.index_size = 4;
-         break;
-      case GL_UNSIGNED_SHORT:
-         ibuffer.index_size = 2;
-         break;
-      case GL_UNSIGNED_BYTE:
-         ibuffer.index_size = 1;
-         break;
-      default:
-         assert(0);
-	 goto out_unref_vertex;
-      }
+      ibuffer.index_size = vbo_sizeof_ib_type(ib->type);
+      if (ibuffer.index_size == 0)
+         goto out_unref_vertex;
 
       if (bufobj && bufobj->Name) {
          struct st_buffer_object *stobj = st_buffer_object(bufobj);