Mesa (master): i965/Gen6-7: Fix point sprites with PolygonMode(GL_POINT)

[Chris Forbes]

Module: Mesa
Branch: master
Commit: ed56c16820aea0e115768d77861fe266380f2595
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=ed56c16820aea0e115768d77861fe266380f2595

Author: Chris Forbes <chrisf at ijw.co.nz>
Date:   Fri Dec  5 19:43:13 2014 +1300

i965/Gen6-7: Fix point sprites with PolygonMode(GL_POINT)

This was an oversight in the original patch. When PolygonMode is
used, then front faces, back faces, or both may be rendered as
points and are affected by point sprite state.

Note that SNB/IVB can't actually be fully conformant here, for
a legacy context -- we don't have separate sets of pointsprite
enables for front and back faces. Haswell ignores pointsprite
state correctly in hardware for non-point rasterization, so can
do this correctly, but it doesn't seem worth it.

Signed-off-by: Chris Forbes <chrisf at ijw.co.nz>
Cc: "10.4" <mesa-stable at lists.freedesktop.org>
Bugzilla: https://bugs.freedesktop.org/show_bug.cgi?id=86764
Reviewed-by: Matt Turner <mattst88 at gmail.com>

---

 src/mesa/drivers/dri/i965/gen6_sf_state.c |    6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/src/mesa/drivers/dri/i965/gen6_sf_state.c b/src/mesa/drivers/dri/i965/gen6_sf_state.c
index ccb6b30..fc73c57 100644
--- a/src/mesa/drivers/dri/i965/gen6_sf_state.c
+++ b/src/mesa/drivers/dri/i965/gen6_sf_state.c
@@ -133,6 +133,12 @@ static bool
 is_drawing_points(const struct brw_context *brw)
 {
    /* Determine if the primitives *reaching the SF* are points */
+   /* _NEW_POLYGON */
+   if (brw->ctx.Polygon.FrontMode == GL_POINT ||
+       brw->ctx.Polygon.BackMode == GL_POINT) {
+      return true;
+   }
+
    if (brw->geometry_program) {
       /* BRW_NEW_GEOMETRY_PROGRAM */
       return brw->geometry_program->OutputType == GL_POINTS;