i965 Gen4/5: clip: correctly handle flat varyings

Previously we only gave special treatment to the builtin color varyings.
This patch adds support for arbitrary flat-shaded varyings, which is
required for GLSL 1.30.

Based on Olivier Galibert's patch from last year:
http://lists.freedesktop.org/archives/mesa-dev/2012-July/024340.html

V5: Move key.do_flat_shading to brw_clip_compile.has_flat_shading
V6: Real bools.

[V1-2]: Signed-off-by: Olivier Galibert <galibert at pobox.com>
Signed-off-by: Chris Forbes <[email protected]>
Reviewed-by: Kenneth Graunke <[email protected]>

1 files changed, 4 insertions, 1 deletions

diff --git a/src/mesa/drivers/dri/i965/brw_clip.c b/src/mesa/drivers/dri/i965/brw_clip.c
index 7621675969d..1c2a4bc6eb8 100644
--- a/src/mesa/drivers/dri/i965/brw_clip.c
+++ b/src/mesa/drivers/dri/i965/brw_clip.c
@@ -70,6 +70,9 @@ static void compile_clip_prog( struct brw_context *brw,
    c.key = *key;
    c.vue_map = brw->vue_map_geom_out;
 
+   c.has_flat_shading =
+      brw_any_flat_varyings(&key->interpolation_mode);
+
    /* nr_regs is the number of registers filled by reading data from the VUE.
     * This program accesses the entire VUE, so nr_regs needs to be the size of
     * the VUE (measured in pairs, since two slots are stored in each
@@ -149,8 +152,8 @@ brw_upload_clip_prog(struct brw_context *brw)
    key.primitive = brw->reduced_primitive;
    /* BRW_NEW_VUE_MAP_GEOM_OUT */
    key.attrs = brw->vue_map_geom_out.slots_valid;
+
    /* _NEW_LIGHT */
-   key.do_flat_shading = (ctx->Light.ShadeModel == GL_FLAT);
    key.pv_first = (ctx->Light.ProvokingVertex == GL_FIRST_VERTEX_CONVENTION);
    /* _NEW_TRANSFORM (also part of VUE map)*/
    key.nr_userclip = _mesa_bitcount_64(ctx->Transform.ClipPlanesEnabled);