Mesa (master): i965/clip: Removing scissor atom

[Ben Widawsky]

Module: Mesa
Branch: master
Commit: 38e181bad283eb5dea207cf6a6b8b50efd13b5ed
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=38e181bad283eb5dea207cf6a6b8b50efd13b5ed

Author: Ben Widawsky <benjamin.widawsky at intel.com>
Date:   Wed Jul 30 11:39:06 2014 -0700

i965/clip: Removing scissor atom

Now that we no longer use ctx->DrawBuffer->_Xmin and related fields to
program the screen-space viewport extents, we don't depend on any
scissoring state.  So we can drop the +_NEW_SCISSOR dependency.

On GEN8, a change in scissor state does not effect anything for the
clipper/sf hardware state. The hardware will always do the right thing
once the viewport extents are programmed. We can therefore remove the
unecessary state emission.

Ken originally spotted this.

v2: Reword the commit message. Remove spurious hunk.

Reviewed-by: Kenneth Graunke <kenneth at whitecape.org>

---

 src/mesa/drivers/dri/i965/gen8_viewport_state.c |    4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/mesa/drivers/dri/i965/gen8_viewport_state.c b/src/mesa/drivers/dri/i965/gen8_viewport_state.c
index 04a4530..9c89532 100644
--- a/src/mesa/drivers/dri/i965/gen8_viewport_state.c
+++ b/src/mesa/drivers/dri/i965/gen8_viewport_state.c
@@ -100,7 +100,7 @@ gen8_upload_sf_clip_viewport(struct brw_context *brw)
       vp[10] = -gby; /* y-min */
       vp[11] =  gby; /* y-max */
 
-      /* _NEW_SCISSOR | _NEW_VIEWPORT | _NEW_BUFFERS: Screen Space Viewport
+      /* _NEW_VIEWPORT | _NEW_BUFFERS: Screen Space Viewport
        * The hardware will take the intersection of the drawing rectangle,
        * scissor rectangle, and the viewport extents. We don't need to be
        * smart, and can therefore just program the viewport extents.
@@ -130,7 +130,7 @@ gen8_upload_sf_clip_viewport(struct brw_context *brw)
 
 const struct brw_tracked_state gen8_sf_clip_viewport = {
    .dirty = {
-      .mesa = _NEW_BUFFERS | _NEW_SCISSOR | _NEW_VIEWPORT,
+      .mesa = _NEW_BUFFERS | _NEW_VIEWPORT,
       .brw = BRW_NEW_BATCH,
       .cache = 0,
    },