Mesa (mesa_7_6_branch): Improve implementation of GL_POINT_SPRITE_COORD_ORIGIN errors

[Ian Romanick]

Module: Mesa
Branch: mesa_7_6_branch
Commit: 0528f40e3b8ca3e59d3a641c4504d34cf9364578
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=0528f40e3b8ca3e59d3a641c4504d34cf9364578

Author: Ian Romanick <ian.d.romanick at intel.com>
Date:   Wed Nov 25 16:31:28 2009 -0800

Improve implementation of GL_POINT_SPRITE_COORD_ORIGIN errors

This enum is only supported for OpenGL 2.0.  If a driver supports
OpenGL 1.4 and GL_ARB_point_sprite, using this enum should generate an
error.  This is important because, for example, i915 and i830 can
support GL_ARB_point_sprite, but they cannot support
GL_POINT_SPRITE_COORD_ORIGIN.

This commit just removes the check for NV_point_sprite, which is
completely wrong, and add some comments describing what the code
should do.  I don't see an easy way to check for version >= 2.0 from
inside Mesa.  Perhaps we should add an extension
GL_MESA_point_sprite_20 (like Intel's old GL_EXT_packed_pixels_12) to
indicate that this added bit of functionality is available.

Also note that glean's pointSprite test only checks for
GL_ARB_point_sprite before trying to use
GL_POINT_SPRITE_COORD_ORIGIN.  Naturally, that fails on
non-2.0 implementations (i.e., Mac OS X on GMA 950).

---

 src/mesa/main/points.c |    7 ++++++-
 1 files changed, 6 insertions(+), 1 deletions(-)

diff --git a/src/mesa/main/points.c b/src/mesa/main/points.c
index 4c8fc1f..b330544 100644
--- a/src/mesa/main/points.c
+++ b/src/mesa/main/points.c
@@ -200,7 +200,12 @@ _mesa_PointParameterfv( GLenum pname, const GLfloat *params)
          }
          break;
       case GL_POINT_SPRITE_COORD_ORIGIN:
-         if (ctx->Extensions.ARB_point_sprite || ctx->Extensions.NV_point_sprite) {
+	 /* This is not completely correct.  GL_POINT_SPRITE_COORD_ORIGIN was
+	  * added to point sprites when the extension was merged into OpenGL
+	  * 2.0.  It is expected that an implementation supporting OpenGL 1.4
+	  * and GL_ARB_point_sprite will generate an error here.
+	  */
+         if (ctx->Extensions.ARB_point_sprite) {
             GLenum value = (GLenum) params[0];
             if (value != GL_LOWER_LEFT && value != GL_UPPER_LEFT) {
                _mesa_error(ctx, GL_INVALID_VALUE,