[Mesa-dev] [PATCH] u_vbuf_mgr: restore buffer offsets

[Marek Olšák]

Well spotted, thanks. Some comments below.

On Wed, Jul 20, 2011 at 3:25 PM, Chia-I Wu <olvaffe at gmail.com> wrote:
> From: Chia-I Wu <olv at lunarg.com>
>
> u_vbuf_upload_buffers modifies the buffer offsets.  If they are not
> restored, and any of the vertex formats is not supported natively, the
> next u_vbuf_mgr_draw_begin call will translate the vertex buffers with
> incorrect buffer offsets.
> ---
>  src/gallium/auxiliary/util/u_vbuf_mgr.c |   14 ++++++++++++++
>  1 files changed, 14 insertions(+), 0 deletions(-)
>
> diff --git a/src/gallium/auxiliary/util/u_vbuf_mgr.c b/src/gallium/auxiliary/util/u_vbuf_mgr.c
> index 374fc33..47e7027 100644
> --- a/src/gallium/auxiliary/util/u_vbuf_mgr.c
> +++ b/src/gallium/auxiliary/util/u_vbuf_mgr.c
> @@ -79,6 +79,8 @@ struct u_vbuf_mgr_priv {
>    void *saved_ve, *fallback_ve;
>    boolean ve_binding_lock;
>
> +   unsigned saved_buffer_offset[PIPE_MAX_ATTRIBS];
> +
>    boolean any_user_vbs;
>    boolean incompatible_vb_layout;
>  };
> @@ -488,6 +490,7 @@ void u_vbuf_mgr_set_vertex_buffers(struct u_vbuf_mgr *mgrb,
>
>       pipe_resource_reference(&mgr->b.vertex_buffer[i].buffer, vb->buffer);
>       pipe_resource_reference(&mgr->b.real_vertex_buffer[i], NULL);
> +      mgr->saved_buffer_offset[i] = vb->buffer_offset;
>
>       if (!vb->buffer) {
>          continue;
> @@ -647,6 +650,17 @@ u_vbuf_mgr_draw_begin(struct u_vbuf_mgr *mgrb,
>  void u_vbuf_mgr_draw_end(struct u_vbuf_mgr *mgrb)
>  {
>    struct u_vbuf_mgr_priv *mgr = (struct u_vbuf_mgr_priv*)mgrb;
> +   unsigned i;
> +
> +   /* buffer offsets were modified in u_vbuf_upload_buffers */
> +   if (mgr->any_user_vbs) {

That conditional should probably be:

if (mgr->any_user_vbs || mgr->fallback_ve)

Because the translate fallback changes the buffer offsets too.

> +      for (i = 0; i < mgr->ve->count; i++) {
> +         unsigned index = mgr->ve->ve[i].vertex_buffer_index;
> +         struct pipe_vertex_buffer *vb = &mgr->b.vertex_buffer[index];
> +
> +         vb->buffer_offset = mgr->saved_buffer_offset[index];
> +      }

Why not loop over vertex buffers instead of vertex elements?

Marek

> +   }
>
>    if (mgr->fallback_ve) {
>       u_vbuf_translate_end(mgr);
> --
> 1.7.5.3
>
>