st/mesa: Make the frontbuffer visible on st_flush(PIPE_FLUSH_FRAME).

So far the frontbuffer was only being flushed on st_glFlush and
st_glFinish, however, a co-state tracker may need to make sure that
any frontbuffer changes are already on its way to the actual front.

The dri2 state tracker will need this for event-driven GL applications
to resize properly (It could also be done calling "dri_flush_frontbuffer",
but that way we would flush unnecessarily in the double-buffered case).

Additionally this patch avoids flushing the mesa rendering cache if
PIPE_FLUSH_RENDER_CACHE wasn't specified.

1 files changed, 6 insertions, 9 deletions

diff --git a/src/mesa/state_tracker/st_cb_flush.c b/src/mesa/state_tracker/st_cb_flush.c
index 1329f807bc..0ddfce4682 100644
--- a/src/mesa/state_tracker/st_cb_flush.c
+++ b/src/mesa/state_tracker/st_cb_flush.c
@@ -91,7 +91,8 @@ display_front_buffer(struct st_context *st)
 void st_flush( struct st_context *st, uint pipeFlushFlags,
                struct pipe_fence_handle **fence )
 {
-   FLUSH_CURRENT(st->ctx, 0);
+   if (pipeFlushFlags & PIPE_FLUSH_RENDER_CACHE)
+      FLUSH_CURRENT(st->ctx, 0);
 
    /* Release any vertex buffers that might potentially be accessed in
     * successive frames:
@@ -102,6 +103,10 @@ void st_flush( struct st_context *st, uint pipeFlushFlags,
    util_gen_mipmap_flush(st->gen_mipmap);
 
    st->pipe->flush( st->pipe, pipeFlushFlags, fence );
+
+   if ((pipeFlushFlags & PIPE_FLUSH_FRAME) &&
+       is_front_buffer_dirty(st))
+      display_front_buffer(st);
 }
 
 
@@ -135,10 +140,6 @@ static void st_glFlush(GLcontext *ctx)
     * problems that need to be fixed elsewhere.
     */
    st_flush(st, PIPE_FLUSH_RENDER_CACHE | PIPE_FLUSH_FRAME, NULL);
-
-   if (is_front_buffer_dirty(st)) {
-      display_front_buffer(st);
-   }
 }
 
 
@@ -150,10 +151,6 @@ static void st_glFinish(GLcontext *ctx)
    struct st_context *st = ctx->st;
 
    st_finish(st);
-
-   if (is_front_buffer_dirty(st)) {
-      display_front_buffer(st);
-   }
 }