Merge commit 'lb2/arb_fragment_coord_conventions'

27 files changed, 357 insertions, 14 deletions

diff --git a/src/gallium/auxiliary/tgsi/tgsi_dump.c b/src/gallium/auxiliary/tgsi/tgsi_dump.c
index 5472466eb6..dd36555875 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_dump.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_dump.c
@@ -159,7 +159,9 @@ static const char *property_names[] =
 {
    "GS_INPUT_PRIMITIVE",
    "GS_OUTPUT_PRIMITIVE",
-   "GS_MAX_OUTPUT_VERTICES"
+   "GS_MAX_OUTPUT_VERTICES",
+   "FS_COORD_ORIGIN",
+   "FS_COORD_PIXEL_CENTER"
 };
 
 static const char *primitive_names[] =
@@ -176,6 +178,18 @@ static const char *primitive_names[] =
    "POLYGON"
 };
 
+static const char *fs_coord_origin_names[] =
+{
+   "UPPER_LEFT",
+   "LOWER_LEFT"
+};
+
+static const char *fs_coord_pixel_center_names[] =
+{
+   "HALF_INTEGER",
+   "INTEGER"
+};
+
 
 static void
 _dump_register_dst(
@@ -366,6 +380,12 @@ iter_property(
       case TGSI_PROPERTY_GS_OUTPUT_PRIM:
          ENM(prop->u[i].Data, primitive_names);
          break;
+      case TGSI_PROPERTY_FS_COORD_ORIGIN:
+         ENM(prop->u[i].Data, fs_coord_origin_names);
+         break;
+      case TGSI_PROPERTY_FS_COORD_PIXEL_CENTER:
+         ENM(prop->u[i].Data, fs_coord_pixel_center_names);
+         break;
       default:
          SID( prop->u[i].Data );
          break;
diff --git a/src/gallium/auxiliary/tgsi/tgsi_text.c b/src/gallium/auxiliary/tgsi/tgsi_text.c
index f74b56bfb5..96be353e26 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_text.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_text.c
@@ -1129,7 +1129,9 @@ static const char *property_names[] =
 {
    "GS_INPUT_PRIMITIVE",
    "GS_OUTPUT_PRIMITIVE",
-   "GS_MAX_OUTPUT_VERTICES"
+   "GS_MAX_OUTPUT_VERTICES",
+   "FS_COORD_ORIGIN",
+   "FS_COORD_PIXEL_CENTER"
 };
 
 static const char *primitive_names[] =
@@ -1146,6 +1148,19 @@ static const char *primitive_names[] =
    "POLYGON"
 };
 
+static const char *fs_coord_origin_names[] =
+{
+   "UPPER_LEFT",
+   "LOWER_LEFT"
+};
+
+static const char *fs_coord_pixel_center_names[] =
+{
+   "HALF_INTEGER",
+   "INTEGER"
+};
+
+
 static boolean
 parse_primitive( const char **pcur, uint *primitive )
 {
@@ -1163,6 +1178,40 @@ parse_primitive( const char **pcur, uint *primitive )
    return FALSE;
 }
 
+static boolean
+parse_fs_coord_origin( const char **pcur, uint *fs_coord_origin )
+{
+   uint i;
+
+   for (i = 0; i < sizeof(fs_coord_origin_names) / sizeof(fs_coord_origin_names[0]); i++) {
+      const char *cur = *pcur;
+
+      if (str_match_no_case( &cur, fs_coord_origin_names[i])) {
+         *fs_coord_origin = i;
+         *pcur = cur;
+         return TRUE;
+      }
+   }
+   return FALSE;
+}
+
+static boolean
+parse_fs_coord_pixel_center( const char **pcur, uint *fs_coord_pixel_center )
+{
+   uint i;
+
+   for (i = 0; i < sizeof(fs_coord_pixel_center_names) / sizeof(fs_coord_pixel_center_names[0]); i++) {
+      const char *cur = *pcur;
+
+      if (str_match_no_case( &cur, fs_coord_pixel_center_names[i])) {
+         *fs_coord_pixel_center = i;
+         *pcur = cur;
+         return TRUE;
+      }
+   }
+   return FALSE;
+}
+
 
 static boolean parse_property( struct translate_ctx *ctx )
 {
@@ -1204,6 +1253,18 @@ static boolean parse_property( struct translate_ctx *ctx )
          ctx->implied_array_size = u_vertices_per_prim(values[0]);
       }
       break;
+   case TGSI_PROPERTY_FS_COORD_ORIGIN:
+      if (!parse_fs_coord_origin(&ctx->cur, &values[0] )) {
+         report_error( ctx, "Unknown coord origin as property: must be UPPER_LEFT or LOWER_LEFT!" );
+         return FALSE;
+      }
+      break;
+   case TGSI_PROPERTY_FS_COORD_PIXEL_CENTER:
+      if (!parse_fs_coord_pixel_center(&ctx->cur, &values[0] )) {
+         report_error( ctx, "Unknown coord pixel center as property: must be HALF_INTEGER or INTEGER!" );
+         return FALSE;
+      }
+      break;
    default:
       if (!parse_uint(&ctx->cur, &values[0] )) {
          report_error( ctx, "Expected unsigned integer as property!" );
diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.c b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
index f2610d0764..0ae46785bb 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_ureg.c
+++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.c
@@ -142,6 +142,8 @@ struct ureg_program
    unsigned property_gs_input_prim;
    unsigned property_gs_output_prim;
    unsigned property_gs_max_vertices;
+   unsigned char property_fs_coord_origin; /* = TGSI_FS_COORD_ORIGIN_* */
+   unsigned char property_fs_coord_pixel_center; /* = TGSI_FS_COORD_PIXEL_CENTER_* */
 
    unsigned nr_addrs;
    unsigned nr_preds;
@@ -265,6 +267,20 @@ ureg_property_gs_max_vertices(struct ureg_program *ureg,
    ureg->property_gs_max_vertices = max_vertices;
 }
 
+void
+ureg_property_fs_coord_origin(struct ureg_program *ureg,
+                            unsigned fs_coord_origin)
+{
+   ureg->property_fs_coord_origin = fs_coord_origin;
+}
+
+void
+ureg_property_fs_coord_pixel_center(struct ureg_program *ureg,
+                            unsigned fs_coord_pixel_center)
+{
+   ureg->property_fs_coord_pixel_center = fs_coord_pixel_center;
+}
+
 
 
 struct ureg_src 
@@ -1202,6 +1218,22 @@ static void emit_decls( struct ureg_program *ureg )
                     ureg->property_gs_max_vertices);
    }
 
+   if (ureg->property_fs_coord_origin) {
+      assert(ureg->processor == TGSI_PROCESSOR_FRAGMENT);
+
+      emit_property(ureg,
+                    TGSI_PROPERTY_FS_COORD_ORIGIN,
+                    ureg->property_fs_coord_origin);
+   }
+
+   if (ureg->property_fs_coord_pixel_center) {
+      assert(ureg->processor == TGSI_PROCESSOR_FRAGMENT);
+
+      emit_property(ureg,
+                    TGSI_PROPERTY_FS_COORD_PIXEL_CENTER,
+                    ureg->property_fs_coord_pixel_center);
+   }
+
    if (ureg->processor == TGSI_PROCESSOR_VERTEX) {
       for (i = 0; i < UREG_MAX_INPUT; i++) {
          if (ureg->vs_inputs[i/32] & (1 << (i%32))) {
diff --git a/src/gallium/auxiliary/tgsi/tgsi_ureg.h b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
index 2ac00deca1..e25f35c6dc 100644
--- a/src/gallium/auxiliary/tgsi/tgsi_ureg.h
+++ b/src/gallium/auxiliary/tgsi/tgsi_ureg.h
@@ -136,6 +136,13 @@ void
 ureg_property_gs_max_vertices(struct ureg_program *ureg,
                               unsigned max_vertices);
 
+void
+ureg_property_fs_coord_origin(struct ureg_program *ureg,
+                            unsigned fs_coord_origin);
+
+void
+ureg_property_fs_coord_pixel_center(struct ureg_program *ureg,
+                            unsigned fs_coord_pixel_center);
 
 /***********************************************************************
  * Build shader declarations:
diff --git a/src/gallium/docs/source/screen.rst b/src/gallium/docs/source/screen.rst
index f2421c74ae..0507b81627 100644
--- a/src/gallium/docs/source/screen.rst
+++ b/src/gallium/docs/source/screen.rst
@@ -57,6 +57,14 @@ The integer capabilities:
   only permit binding one constant buffer per shader, and the shaders will
   not permit two-dimensional access to constants.
 * ``MAX_CONST_BUFFER_SIZE``: Maximum byte size of a single constant buffer.
+* ``PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT``: Whether the TGSI property
+  FS_COORD_ORIGIN with value UPPER_LEFT is supported
+* ``PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT``: Whether the TGSI property
+  FS_COORD_ORIGIN with value LOWER_LEFT is supported
+* ``PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER``: Whether the TGSI
+  property FS_COORD_PIXEL_CENTER with value HALF_INTEGER is supported
+* ``PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER``: Whether the TGSI
+  property FS_COORD_PIXEL_CENTER with value INTEGER is supported
 
 The floating-point capabilities:
 
diff --git a/src/gallium/docs/source/tgsi.rst b/src/gallium/docs/source/tgsi.rst
index 2c34a6bae5..3e702ceeda 100644
--- a/src/gallium/docs/source/tgsi.rst
+++ b/src/gallium/docs/source/tgsi.rst
@@ -1319,9 +1319,8 @@ are the Cartesian coordinates, and ``w`` is the homogenous coordinate and used
 for the perspective divide, if enabled.
 
 As a vertex shader output, position should be scaled to the viewport. When
-used in fragment shaders, position will ---
-
-XXX --- wait a minute. Should position be in [0,1] for x and y?
+used in fragment shaders, position will be in window coordinates. The convention
+used depends on the FS_COORD_ORIGIN and FS_COORD_PIXEL_CENTER properties.
 
 XXX additionally, is there a way to configure the perspective divide? it's
 accelerated on most chipsets AFAIK...
@@ -1400,3 +1399,45 @@ TGSI_SEMANTIC_EDGEFLAG
 """"""""""""""""""""""
 
 XXX no clue
+
+
+Properties
+^^^^^^^^^^^^^^^^^^^^^^^^
+
+
+  Properties are general directives that apply to the whole TGSI program.
+
+FS_COORD_ORIGIN
+"""""""""""""""
+
+Specifies the fragment shader TGSI_SEMANTIC_POSITION coordinate origin.
+The default value is UPPER_LEFT.
+
+If UPPER_LEFT, the position will be (0,0) at the upper left corner and
+increase downward and rightward.
+If LOWER_LEFT, the position will be (0,0) at the lower left corner and
+increase upward and rightward.
+
+OpenGL defaults to LOWER_LEFT, and is configurable with the
+GL_ARB_fragment_coord_conventions extension.
+
+DirectX 9/10 use UPPER_LEFT.
+
+FS_COORD_PIXEL_CENTER
+"""""""""""""""""""""
+
+Specifies the fragment shader TGSI_SEMANTIC_POSITION pixel center convention.
+The default value is HALF_INTEGER.
+
+If HALF_INTEGER, the fractionary part of the position will be 0.5
+If INTEGER, the fractionary part of the position will be 0.0
+
+Note that this does not affect the set of fragments generated by
+rasterization, which is instead controlled by gl_rasterization_rules in the
+rasterizer.
+
+OpenGL defaults to HALF_INTEGER, and is configurable with the
+GL_ARB_fragment_coord_conventions extension.
+
+DirectX 9 uses INTEGER.
+DirectX 10 uses HALF_INTEGER.
diff --git a/src/gallium/drivers/cell/ppu/cell_screen.c b/src/gallium/drivers/cell/ppu/cell_screen.c
index d185c6b849..37b04396b3 100644
--- a/src/gallium/drivers/cell/ppu/cell_screen.c
+++ b/src/gallium/drivers/cell/ppu/cell_screen.c
@@ -86,6 +86,12 @@ cell_get_param(struct pipe_screen *screen, int param)
       return 0; /* XXX to do */
    case PIPE_CAP_TGSI_CONT_SUPPORTED:
       return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+      return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 0;
    default:
       return 0;
    }
diff --git a/src/gallium/drivers/i915/i915_screen.c b/src/gallium/drivers/i915/i915_screen.c
index d4ee8f5339..7b8d66b8aa 100644
--- a/src/gallium/drivers/i915/i915_screen.c
+++ b/src/gallium/drivers/i915/i915_screen.c
@@ -117,6 +117,12 @@ i915_get_param(struct pipe_screen *screen, int param)
       return 8;  /* max 128x128x128 */
    case PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS:
       return 11; /* max 1024x1024 */
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+      return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 0;
    default:
       return 0;
    }
diff --git a/src/gallium/drivers/i965/brw_screen.c b/src/gallium/drivers/i965/brw_screen.c
index a3728fb16e..a8f9892d71 100644
--- a/src/gallium/drivers/i965/brw_screen.c
+++ b/src/gallium/drivers/i965/brw_screen.c
@@ -175,6 +175,12 @@ brw_get_param(struct pipe_screen *screen, int param)
       return 8;  /* max 128x128x128 */
    case PIPE_CAP_MAX_TEXTURE_CUBE_LEVELS:
       return 11; /* max 1024x1024 */
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+      return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 0;
    default:
       return 0;
    }
diff --git a/src/gallium/drivers/llvmpipe/lp_screen.c b/src/gallium/drivers/llvmpipe/lp_screen.c
index f04c0320ba..902009d90b 100644
--- a/src/gallium/drivers/llvmpipe/lp_screen.c
+++ b/src/gallium/drivers/llvmpipe/lp_screen.c
@@ -114,6 +114,12 @@ llvmpipe_get_param(struct pipe_screen *screen, int param)
       return 0;
    case PIPE_CAP_INDEP_BLEND_FUNC:
       return 0;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+      return 0;
    default:
       return 0;
    }
diff --git a/src/gallium/drivers/nv04/nv04_screen.c b/src/gallium/drivers/nv04/nv04_screen.c
index 4eba772575..97538964af 100644
--- a/src/gallium/drivers/nv04/nv04_screen.c
+++ b/src/gallium/drivers/nv04/nv04_screen.c
@@ -49,6 +49,12 @@ nv04_screen_get_param(struct pipe_screen *screen, int param)
 		return 0;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/nv10/nv10_screen.c b/src/gallium/drivers/nv10/nv10_screen.c
index 2dabc4509f..4e6bc12994 100644
--- a/src/gallium/drivers/nv10/nv10_screen.c
+++ b/src/gallium/drivers/nv10/nv10_screen.c
@@ -44,6 +44,12 @@ nv10_screen_get_param(struct pipe_screen *screen, int param)
 		return 0;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/nv20/nv20_screen.c b/src/gallium/drivers/nv20/nv20_screen.c
index 7782cbe3a8..df9401bcce 100644
--- a/src/gallium/drivers/nv20/nv20_screen.c
+++ b/src/gallium/drivers/nv20/nv20_screen.c
@@ -44,6 +44,12 @@ nv20_screen_get_param(struct pipe_screen *screen, int param)
 		return 0;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/nv30/nv30_screen.c b/src/gallium/drivers/nv30/nv30_screen.c
index 8f8f3ea1a9..ee83ec5676 100644
--- a/src/gallium/drivers/nv30/nv30_screen.c
+++ b/src/gallium/drivers/nv30/nv30_screen.c
@@ -71,6 +71,12 @@ nv30_screen_get_param(struct pipe_screen *pscreen, int param)
 		return 0;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/nv40/nv40_screen.c b/src/gallium/drivers/nv40/nv40_screen.c
index 4eab5daa80..b1a7343b40 100644
--- a/src/gallium/drivers/nv40/nv40_screen.c
+++ b/src/gallium/drivers/nv40/nv40_screen.c
@@ -56,6 +56,12 @@ nv40_screen_get_param(struct pipe_screen *pscreen, int param)
 		return 0;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/nv50/nv50_screen.c b/src/gallium/drivers/nv50/nv50_screen.c
index 6af9700c1a..c4465a228c 100644
--- a/src/gallium/drivers/nv50/nv50_screen.c
+++ b/src/gallium/drivers/nv50/nv50_screen.c
@@ -139,6 +139,12 @@ nv50_screen_get_param(struct pipe_screen *pscreen, int param)
 		return 1;
 	case PIPE_CAP_INDEP_BLEND_FUNC:
 		return 0;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+		return 1;
+	case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+	case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+		return 0;
 	default:
 		NOUVEAU_ERR("Unknown PIPE_CAP %d\n", param);
 		return 0;
diff --git a/src/gallium/drivers/r300/r300_screen.c b/src/gallium/drivers/r300/r300_screen.c
index 679a5644af..f311284d15 100644
--- a/src/gallium/drivers/r300/r300_screen.c
+++ b/src/gallium/drivers/r300/r300_screen.c
@@ -156,6 +156,12 @@ static int r300_get_param(struct pipe_screen* pscreen, int param)
             return 1;
         case PIPE_CAP_INDEP_BLEND_FUNC:
             return 0;
+        case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+        case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+	    return 1;
+        case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+        case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+            return 0;
         default:
             debug_printf("r300: Implementation error: Bad param %d\n",
                 param);
diff --git a/src/gallium/drivers/softpipe/sp_screen.c b/src/gallium/drivers/softpipe/sp_screen.c
index b2841f4103..714a1cf534 100644
--- a/src/gallium/drivers/softpipe/sp_screen.c
+++ b/src/gallium/drivers/softpipe/sp_screen.c
@@ -99,6 +99,11 @@ softpipe_get_param(struct pipe_screen *screen, int param)
       return 1;
    case PIPE_CAP_INDEP_BLEND_FUNC:
       return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 1;
    default:
       return 0;
    }
diff --git a/src/gallium/drivers/softpipe/sp_setup.c b/src/gallium/drivers/softpipe/sp_setup.c
index ba1f0f0b2e..bb1bff581c 100644
--- a/src/gallium/drivers/softpipe/sp_setup.c
+++ b/src/gallium/drivers/softpipe/sp_setup.c
@@ -504,21 +504,24 @@ static void tri_persp_coeff( struct setup_context *setup,
 
 /**
  * Special coefficient setup for gl_FragCoord.
- * X and Y are trivial, though Y has to be inverted for OpenGL.
+ * X and Y are trivial, though Y may have to be inverted for OpenGL.
  * Z and W are copied from posCoef which should have already been computed.
  * We could do a bit less work if we'd examine gl_FragCoord's swizzle mask.
  */
 static void
 setup_fragcoord_coeff(struct setup_context *setup, uint slot)
 {
+   struct sp_fragment_shader* spfs = setup->softpipe->fs;
    /*X*/
-   setup->coef[slot].a0[0] = 0;
+   setup->coef[slot].a0[0] = spfs->pixel_center_integer ? 0.0 : 0.5;
    setup->coef[slot].dadx[0] = 1.0;
    setup->coef[slot].dady[0] = 0.0;
    /*Y*/
-   setup->coef[slot].a0[1] = 0.0;
+   setup->coef[slot].a0[1] =
+		   (spfs->origin_lower_left ? setup->softpipe->framebuffer.height : 0)
+		   + (spfs->pixel_center_integer ? 0.0 : 0.5);
    setup->coef[slot].dadx[1] = 0.0;
-   setup->coef[slot].dady[1] = 1.0;
+   setup->coef[slot].dady[1] = spfs->origin_lower_left ? -1.0 : 1.0;
    /*Z*/
    setup->coef[slot].a0[2] = setup->posCoef.a0[2];
    setup->coef[slot].dadx[2] = setup->posCoef.dadx[2];
diff --git a/src/gallium/drivers/softpipe/sp_state.h b/src/gallium/drivers/softpipe/sp_state.h
index 7f244c4fd4..a83cae7361 100644
--- a/src/gallium/drivers/softpipe/sp_state.h
+++ b/src/gallium/drivers/softpipe/sp_state.h
@@ -68,6 +68,9 @@ struct sp_fragment_shader {
 
    struct tgsi_shader_info info;
 
+   boolean origin_lower_left; /**< fragment shader uses lower left position origin? */
+   boolean pixel_center_integer; /**< fragment shader uses integer pixel center? */
+
    void (*prepare)( const struct sp_fragment_shader *shader,
 		    struct tgsi_exec_machine *machine,
 		    struct tgsi_sampler **samplers);
diff --git a/src/gallium/drivers/softpipe/sp_state_fs.c b/src/gallium/drivers/softpipe/sp_state_fs.c
index 04bdcaacc2..de3edde976 100644
--- a/src/gallium/drivers/softpipe/sp_state_fs.c
+++ b/src/gallium/drivers/softpipe/sp_state_fs.c
@@ -44,6 +44,7 @@ softpipe_create_fs_state(struct pipe_context *pipe,
 {
    struct softpipe_context *softpipe = softpipe_context(pipe);
    struct sp_fragment_shader *state;
+   unsigned i;
 
    /* debug */
    if (softpipe->dump_fs) 
@@ -60,6 +61,13 @@ softpipe_create_fs_state(struct pipe_context *pipe,
    /* get/save the summary info for this shader */
    tgsi_scan_shader(templ->tokens, &state->info);
 
+   for (i = 0; i < state->info.num_properties; ++i) {
+      if (state->info.properties[i].name == TGSI_PROPERTY_FS_COORD_ORIGIN)
+         state->origin_lower_left = state->info.properties[i].data[0];
+      else if (state->info.properties[i].name == TGSI_PROPERTY_FS_COORD_PIXEL_CENTER)
+	 state->pixel_center_integer = state->info.properties[i].data[0];
+   }
+
    return state;
 }
 
diff --git a/src/gallium/drivers/svga/svga_screen.c b/src/gallium/drivers/svga/svga_screen.c
index cd1ed7bac8..c9db9ac874 100644
--- a/src/gallium/drivers/svga/svga_screen.c
+++ b/src/gallium/drivers/svga/svga_screen.c
@@ -144,6 +144,13 @@ svga_get_paramf(struct pipe_screen *screen, int param)
    case PIPE_CAP_BLEND_EQUATION_SEPARATE: /* req. for GL 1.5 */
       return 1;
 
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER:
+      return 1;
+   case PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT:
+   case PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER:
+      return 0;
+
    default:
       return 0;
    }
diff --git a/src/gallium/include/pipe/p_defines.h b/src/gallium/include/pipe/p_defines.h
index b28441dca9..63ba3119b8 100644
--- a/src/gallium/include/pipe/p_defines.h
+++ b/src/gallium/include/pipe/p_defines.h
@@ -409,6 +409,10 @@ enum pipe_transfer_usage {
 #define PIPE_CAP_MAX_CONST_BUFFER_SIZE   33  /*< In bytes */
 #define PIPE_CAP_INDEP_BLEND_ENABLE      34  /*< blend enables and write masks per rendertarget */
 #define PIPE_CAP_INDEP_BLEND_FUNC        35  /*< different blend funcs per rendertarget */
+#define PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT 36
+#define PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT 37
+#define PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER 38
+#define PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER 39
 
 
 /**
diff --git a/src/gallium/include/pipe/p_shader_tokens.h b/src/gallium/include/pipe/p_shader_tokens.h
index b47f4971f1..21581a4674 100644
--- a/src/gallium/include/pipe/p_shader_tokens.h
+++ b/src/gallium/include/pipe/p_shader_tokens.h
@@ -170,7 +170,9 @@ union tgsi_immediate_data
 #define TGSI_PROPERTY_GS_INPUT_PRIM          0
 #define TGSI_PROPERTY_GS_OUTPUT_PRIM         1
 #define TGSI_PROPERTY_GS_MAX_VERTICES        2
-#define TGSI_PROPERTY_COUNT                  3
+#define TGSI_PROPERTY_FS_COORD_ORIGIN        3
+#define TGSI_PROPERTY_FS_COORD_PIXEL_CENTER  4
+#define TGSI_PROPERTY_COUNT                  5
 
 struct tgsi_property {
    unsigned Type         : 4;  /**< TGSI_TOKEN_TYPE_PROPERTY */
@@ -179,6 +181,12 @@ struct tgsi_property {
    unsigned Padding      : 12;
 };
 
+#define TGSI_FS_COORD_ORIGIN_UPPER_LEFT 0
+#define TGSI_FS_COORD_ORIGIN_LOWER_LEFT 1
+
+#define TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER 0
+#define TGSI_FS_COORD_PIXEL_CENTER_INTEGER 1
+
 struct tgsi_property_data {
    unsigned Data;
 };
diff --git a/src/mesa/main/extensions.c b/src/mesa/main/extensions.c
index 73be24d80c..e1320224a8 100644
--- a/src/mesa/main/extensions.c
+++ b/src/mesa/main/extensions.c
@@ -50,7 +50,8 @@ static const struct {
    { OFF, "GL_ARB_depth_clamp",                F(ARB_depth_clamp) },
    { ON,  "GL_ARB_draw_buffers",               F(ARB_draw_buffers) },
    { OFF, "GL_ARB_draw_elements_base_vertex",  F(ARB_draw_elements_base_vertex) },
-   { OFF, "GL_ARB_fragment_coord_conventions", F(ARB_fragment_coord_conventions) },
+   /* TODO: uncomment the following line once GLSL layout(...) support is implemented */
+   /* { OFF, "GL_ARB_fragment_coord_conventions", F(ARB_fragment_coord_conventions) }, */
    { OFF, "GL_ARB_fragment_program",           F(ARB_fragment_program) },
    { OFF, "GL_ARB_fragment_program_shadow",    F(ARB_fragment_program_shadow) },
    { OFF, "GL_ARB_fragment_shader",            F(ARB_fragment_shader) },
diff --git a/src/mesa/state_tracker/st_extensions.c b/src/mesa/state_tracker/st_extensions.c
index 31c03c0783..f2a62f9b69 100644
--- a/src/mesa/state_tracker/st_extensions.c
+++ b/src/mesa/state_tracker/st_extensions.c
@@ -147,6 +147,7 @@ void st_init_extensions(struct st_context *st)
     * Extensions that are supported by all Gallium drivers:
     */
    ctx->Extensions.ARB_copy_buffer = GL_TRUE;
+   ctx->Extensions.ARB_fragment_coord_conventions = GL_TRUE;
    ctx->Extensions.ARB_fragment_program = GL_TRUE;
    ctx->Extensions.ARB_map_buffer_range = GL_TRUE;
    ctx->Extensions.ARB_multisample = GL_TRUE;
diff --git a/src/mesa/state_tracker/st_mesa_to_tgsi.c b/src/mesa/state_tracker/st_mesa_to_tgsi.c
index 05b56c9b58..4aed2df8c3 100644
--- a/src/mesa/state_tracker/st_mesa_to_tgsi.c
+++ b/src/mesa/state_tracker/st_mesa_to_tgsi.c
@@ -34,8 +34,10 @@
 #include "pipe/p_compiler.h"
 #include "pipe/p_shader_tokens.h"
 #include "pipe/p_state.h"
+#include "pipe/p_context.h"
 #include "tgsi/tgsi_ureg.h"
 #include "st_mesa_to_tgsi.h"
+#include "st_context.h"
 #include "shader/prog_instruction.h"
 #include "shader/prog_parameter.h"
 #include "shader/prog_print.h"
@@ -665,6 +667,22 @@ compile_instruction(
    }
 }
 
+/**
+ * Emit the TGSI instructions to adjust the WPOS pixel center convention
+ */
+static void
+emit_adjusted_wpos( struct st_translate *t,
+                    const struct gl_program *program, GLfloat value)
+{
+   struct ureg_program *ureg = t->ureg;
+   struct ureg_dst wpos_temp = ureg_DECL_temporary(ureg);
+   struct ureg_src wpos_input = t->inputs[t->inputMapping[FRAG_ATTRIB_WPOS]];
+
+   ureg_ADD(ureg, ureg_writemask(wpos_temp, TGSI_WRITEMASK_X | TGSI_WRITEMASK_Y),
+		   wpos_input, ureg_imm1f(ureg, value));
+
+   t->inputs[t->inputMapping[FRAG_ATTRIB_WPOS]] = ureg_src(wpos_temp);
+}
 
 /**
  * Emit the TGSI instructions for inverting the WPOS y coordinate.
@@ -690,12 +708,17 @@ emit_inverted_wpos( struct st_translate *t,
                                                        winSizeState);
 
    struct ureg_src winsize = ureg_DECL_constant( ureg, winHeightConst );
-   struct ureg_dst wpos_temp = ureg_DECL_temporary( ureg );
+   struct ureg_dst wpos_temp;
    struct ureg_src wpos_input = t->inputs[t->inputMapping[FRAG_ATTRIB_WPOS]];
 
    /* MOV wpos_temp, input[wpos]
     */
-   ureg_MOV( ureg, wpos_temp, wpos_input );
+   if (wpos_input.File == TGSI_FILE_TEMPORARY)
+      wpos_temp = ureg_dst(wpos_input);
+   else {
+      wpos_temp = ureg_DECL_temporary( ureg );
+      ureg_MOV( ureg, wpos_temp, wpos_input );
+   }
 
    /* SUB wpos_temp.y, winsize_const, wpos_input
     */
@@ -801,6 +824,7 @@ st_translate_mesa_program(
     * Declare input attributes.
     */
    if (procType == TGSI_PROCESSOR_FRAGMENT) {
+      struct gl_fragment_program* fp = (struct gl_fragment_program*)program;
       for (i = 0; i < numInputs; i++) {
          t->inputs[i] = ureg_DECL_fs_input(ureg,
                                            inputSemanticName[i],
@@ -812,7 +836,51 @@ st_translate_mesa_program(
          /* Must do this after setting up t->inputs, and before
           * emitting constant references, below:
           */
-         emit_inverted_wpos( t, program );
+         struct pipe_screen* pscreen = st_context(ctx)->pipe->screen;
+         boolean invert = FALSE;
+
+         if (fp->OriginUpperLeft) {
+            if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT)) {
+            }
+            else if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT)) {
+               ureg_property_fs_coord_origin(ureg, TGSI_FS_COORD_ORIGIN_LOWER_LEFT);
+               invert = TRUE;
+            }
+            else
+               assert(0);
+         }
+         else {
+            if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_ORIGIN_LOWER_LEFT))
+               ureg_property_fs_coord_origin(ureg, TGSI_FS_COORD_ORIGIN_LOWER_LEFT);
+            else if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_ORIGIN_UPPER_LEFT))
+               invert = TRUE;
+            else
+               assert(0);
+         }
+
+         if (fp->PixelCenterInteger) {
+            if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER))
+               ureg_property_fs_coord_pixel_center(ureg, TGSI_FS_COORD_PIXEL_CENTER_INTEGER);
+            else if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER))
+               emit_adjusted_wpos(t, program, invert ? 0.5f : -0.5f);
+            else
+               assert(0);
+         }
+         else {
+            if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_HALF_INTEGER)) {
+            }
+            else if (pscreen->get_param(pscreen, PIPE_CAP_TGSI_FS_COORD_PIXEL_CENTER_INTEGER)) {
+               ureg_property_fs_coord_pixel_center(ureg, TGSI_FS_COORD_PIXEL_CENTER_INTEGER);
+               emit_adjusted_wpos(t, program, invert ? -0.5f : 0.5f);
+            }
+            else
+               assert(0);
+         }
+
+         /* we invert after adjustment so that we avoid the MOV to temporary,
+          * and reuse the adjustment ADD instead */
+         if (invert)
+            emit_inverted_wpos(t, program);
       }
 
       if (program->InputsRead & FRAG_BIT_FACE) {