[Mesa-dev] [PATCH 5/5] gallium: Enable ARB_clip_control for gallium drivers.

[Mathias.Froehlich at gmx.net]

From: Mathias Fröhlich <Mathias.Froehlich at gmx.net>

Gallium should be prepared fine for ARB_clip_control.
So enable this and mention it in the release notes.

v2:
Only enable for drivers announcing the freshly introduced
PIPE_CAP_CLIP_HALFZ capability.

Signed-off-by: Mathias Froehlich <Mathias.Froehlich at web.de>
---
 docs/GL3.txt                                |  2 +-
 docs/relnotes/10.4.html                     |  1 +
 src/mesa/state_tracker/st_atom_rasterizer.c | 14 +++++++++++++-
 src/mesa/state_tracker/st_extensions.c      |  5 +++++
 4 files changed, 20 insertions(+), 2 deletions(-)

diff --git a/docs/GL3.txt b/docs/GL3.txt
index 07d1d2c..35b7678 100644
--- a/docs/GL3.txt
+++ b/docs/GL3.txt
@@ -187,7 +187,7 @@ GL 4.4, GLSL 4.40:
 GL 4.5, GLSL 4.50:
 
   GL_ARB_ES3_1_compatibility                           not started
-  GL_ARB_clip_control                                  not started
+  GL_ARB_clip_control                                  DONE (llvmpipe, softpipe)
   GL_ARB_conditional_render_inverted                   DONE (i965, nvc0, llvmpipe, softpipe)
   GL_ARB_cull_distance                                 not started
   GL_ARB_derivative_control                            DONE (i965, nv50, nvc0, r600)
diff --git a/docs/relnotes/10.4.html b/docs/relnotes/10.4.html
index 64cbfae..4c7af47 100644
--- a/docs/relnotes/10.4.html
+++ b/docs/relnotes/10.4.html
@@ -46,6 +46,7 @@ Note: some of the new features are only available with certain drivers.
 <ul>
 <li>GL_ARB_sample_shading on r600</li>
 <li>GL_ARB_texture_view on nv50, nvc0</li>
+<li>GL_ARB_clip_control on llvmpipe, softpipe</li>
 </ul>
 
 
diff --git a/src/mesa/state_tracker/st_atom_rasterizer.c b/src/mesa/state_tracker/st_atom_rasterizer.c
index dfa728b..31d7776 100644
--- a/src/mesa/state_tracker/st_atom_rasterizer.c
+++ b/src/mesa/state_tracker/st_atom_rasterizer.c
@@ -72,6 +72,11 @@ static void update_raster_state( struct st_context *st )
    {
       raster->front_ccw = (ctx->Polygon.FrontFace == GL_CCW);
 
+      /* _NEW_VIEWPORT */
+      if (ctx->ClipControl.Origin == GL_UPPER_LEFT) {
+         raster->front_ccw ^= 1;
+      }
+
       /*
        * Gallium's surfaces are Y=0=TOP orientation.  OpenGL is the
        * opposite.  Window system surfaces are Y=0=TOP.  Mesa's FBOs
@@ -241,6 +246,12 @@ static void update_raster_state( struct st_context *st )
    raster->half_pixel_center = 1;
    if (st_fb_orientation(ctx->DrawBuffer) == Y_0_TOP)
       raster->bottom_edge_rule = 1;
+   /* _NEW_VIEWPORT */
+   if (ctx->ClipControl.Origin == GL_UPPER_LEFT)
+      raster->bottom_edge_rule ^= 1;
+
+   /* _NEW_VIEWPORT */
+   raster->clip_halfz = (ctx->ClipControl.Depth == GL_ZERO_TO_ONE);
 
    /* ST_NEW_RASTERIZER */
    raster->rasterizer_discard = ctx->RasterDiscard;
@@ -272,7 +283,8 @@ const struct st_tracked_state st_update_rasterizer = {
        _NEW_PROGRAM |
        _NEW_SCISSOR |
        _NEW_FRAG_CLAMP |
-       _NEW_TRANSFORM),      /* mesa state dependencies*/
+       _NEW_TRANSFORM |
+       _NEW_VIEWPORT),      /* mesa state dependencies*/
       (ST_NEW_VERTEX_PROGRAM |
        ST_NEW_RASTERIZER),  /* state tracker dependencies */
    },
diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 78bfe30..4a3f055 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -889,4 +889,9 @@ void st_init_extensions(struct pipe_screen *screen,
                                PIPE_VIDEO_CAP_SUPPORTS_INTERLACED)) {
       extensions->NV_vdpau_interop = GL_TRUE;
    }
+
+   /* ARB_clip_control */
+   if (screen->get_param(screen, PIPE_CAP_CLIP_HALFZ)) {
+      extensions->ARB_clip_control = GL_TRUE;
+   }
 }
-- 
1.9.3