Mesa (master): t_dd_dmatmp: Allow flat shaded polygons with tri fans

[Ian Romanick]

Module: Mesa
Branch: master
Commit: b15b4581d15684d59e1fc4d7cad72ece4dd9fcb0
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=b15b4581d15684d59e1fc4d7cad72ece4dd9fcb0

Author: Ville Syrjälä <ville.syrjala at linux.intel.com>
Date:   Mon Mar 23 14:47:18 2015 +0200

t_dd_dmatmp: Allow flat shaded polygons with tri fans

We can allow rendering flat shaded polygons using tri fans if we check
the provoking vertex convention.

v2 (idr): Remove _EXT suffixes from GL_FIRST_VERTEX_CONVENTION.

Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

---

 src/mesa/tnl_dd/t_dd_dmatmp.h |    6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/src/mesa/tnl_dd/t_dd_dmatmp.h b/src/mesa/tnl_dd/t_dd_dmatmp.h
index 181cf67..7d03b02 100644
--- a/src/mesa/tnl_dd/t_dd_dmatmp.h
+++ b/src/mesa/tnl_dd/t_dd_dmatmp.h
@@ -316,7 +316,8 @@ static void TAG(render_poly_verts)(struct gl_context *ctx,
       }
 
       FLUSH();
-   } else if (ctx->Light.ShadeModel == GL_SMOOTH) {
+   } else if (ctx->Light.ShadeModel == GL_SMOOTH ||
+              ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION) {
       TAG(render_tri_fan_verts)( ctx, start, count, flags );
    } else {
       unreachable("Cannot draw primitive; validate_render should have "
@@ -458,7 +459,8 @@ static bool TAG(validate_render)(struct gl_context *ctx,
          ok = true;
          break;
       case GL_POLYGON:
-         ok = (HAVE_POLYGONS) || ctx->Light.ShadeModel == GL_SMOOTH;
+         ok = (HAVE_POLYGONS) || ctx->Light.ShadeModel == GL_SMOOTH ||
+              ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION;
          break;
       case GL_QUAD_STRIP:
          ok = VB->Elts ||