gallium: allow setting of the internal stream output offset

D3D10 allows setting of the internal offset of a buffer, which is
in general only incremented via actual stream output writes. By
allowing setting of the internal offset draw_auto is capable
of rendering from buffers which have not been actually streamed
out to. Our interface didn't allow. This change functionally
shouldn't make any difference to OpenGL where instead of an
append_bitmask you just get a real array where -1 means append
(like in D3D) and 0 means do not append.

Signed-off-by: Zack Rusin <[email protected]>
Reviewed-by: Roland Scheidegger <[email protected]>
Reviewed-by: Jose Fonseca <[email protected]>
Reviewed-by: Marek Olšák <[email protected]>

1 files changed, 5 insertions, 3 deletions

diff --git a/src/gallium/auxiliary/draw/draw_pt.c b/src/gallium/auxiliary/draw/draw_pt.c
index e2ff7f9fe9f..3236e523a94 100644
--- a/src/gallium/auxiliary/draw/draw_pt.c
+++ b/src/gallium/auxiliary/draw/draw_pt.c
@@ -431,14 +431,16 @@ draw_pt_arrays_restart(struct draw_context *draw,
  */
 static void
 resolve_draw_info(const struct pipe_draw_info *raw_info,
-                  struct pipe_draw_info *info)
+                  struct pipe_draw_info *info,
+                  struct pipe_vertex_buffer *vertex_buffer)
 {
    memcpy(info, raw_info, sizeof(struct pipe_draw_info));
 
    if (raw_info->count_from_stream_output) {
       struct draw_so_target *target =
          (struct draw_so_target *)info->count_from_stream_output;
-      info->count = target->emitted_vertices;
+      assert(vertex_buffer != NULL);
+      info->count = target->internal_offset / vertex_buffer->stride;
 
       /* Stream output draw can not be indexed */
       debug_assert(!info->indexed);
@@ -467,7 +469,7 @@ draw_vbo(struct draw_context *draw,
     */
    util_fpstate_set_denorms_to_zero(fpstate);
 
-   resolve_draw_info(info, &resolved_info);
+   resolve_draw_info(info, &resolved_info, &(draw->pt.vertex_buffer[0]));
    info = &resolved_info;
 
    assert(info->instance_count > 0);