1 files changed, 83 insertions, 5 deletions

diff --git a/src/gallium/drivers/r300/r300_render.c b/src/gallium/drivers/r300/r300_render.c
index 4c5fb405c6..2d70ec2ac9 100644
--- a/src/gallium/drivers/r300/r300_render.c
+++ b/src/gallium/drivers/r300/r300_render.c
@@ -37,7 +37,6 @@
 #include "r300_reg.h"
 #include "r300_render.h"
 #include "r300_state_derived.h"
-#include "r300_vbo.h"
 
 /* r300_render: Vertex and index buffer primitive emission. */
 #define R300_MAX_VBO_SIZE  (1024 * 1024)
@@ -70,14 +69,67 @@ uint32_t r300_translate_primitive(unsigned prim)
     }
 }
 
+static boolean r300_nothing_to_draw(struct r300_context *r300)
+{
+    return r300->rs_state->rs.scissor &&
+           r300->scissor_state->scissor.empty_area;
+}
+
+static uint32_t r300_provoking_vertex_fixes(struct r300_context *r300,
+                                            unsigned mode)
+{
+    uint32_t color_control = r300->rs_state->color_control;
+
+    /* By default (see r300_state.c:r300_create_rs_state) color_control is
+     * initialized to provoking the first vertex.
+     *
+     * Triangle fans must be reduced to the second vertex, not the first, in
+     * Gallium flatshade-first mode, as per the GL spec.
+     * (http://www.opengl.org/registry/specs/ARB/provoking_vertex.txt)
+     *
+     * Quads never provoke correctly in flatshade-first mode. The first
+     * vertex is never considered as provoking, so only the second, third,
+     * and fourth vertices can be selected, and both "third" and "last" modes
+     * select the fourth vertex. This is probably due to D3D lacking quads.
+     *
+     * Similarly, polygons reduce to the first, not the last, vertex, when in
+     * "last" mode, and all other modes start from the second vertex.
+     *
+     * ~ C.
+     */
+
+    if (r300->rs_state->rs.flatshade_first) {
+        switch (mode) {
+            case PIPE_PRIM_TRIANGLE_FAN:
+                color_control |= R300_GA_COLOR_CONTROL_PROVOKING_VERTEX_SECOND;
+                break;
+            case PIPE_PRIM_QUADS:
+            case PIPE_PRIM_QUAD_STRIP:
+            case PIPE_PRIM_POLYGON:
+                color_control |= R300_GA_COLOR_CONTROL_PROVOKING_VERTEX_LAST;
+                break;
+            default:
+                color_control |= R300_GA_COLOR_CONTROL_PROVOKING_VERTEX_FIRST;
+                break;
+        }
+    } else {
+        color_control |= R300_GA_COLOR_CONTROL_PROVOKING_VERTEX_LAST;
+    }
+
+    return color_control;
+}
+
 static void r300_emit_draw_arrays(struct r300_context *r300,
                                   unsigned mode,
                                   unsigned count)
 {
     CS_LOCALS(r300);
 
-    BEGIN_CS(4);
-    OUT_CS_REG(R300_VAP_VF_MAX_VTX_INDX, count);
+    BEGIN_CS(8);
+    OUT_CS_REG(R300_GA_COLOR_CONTROL,
+            r300_provoking_vertex_fixes(r300, mode));
+    OUT_CS_REG(R300_VAP_VF_MIN_VTX_INDX, 0);
+    OUT_CS_REG(R300_VAP_VF_MAX_VTX_INDX, count - 1);
     OUT_CS_PKT3(R300_PACKET3_3D_DRAW_VBUF_2, 0);
     OUT_CS(R300_VAP_VF_CNTL__PRIM_WALK_VERTEX_LIST | (count << 16) |
            r300_translate_primitive(mode));
@@ -102,7 +154,10 @@ static void r300_emit_draw_elements(struct r300_context *r300,
     assert((start * indexSize)  % 4 == 0);
     assert(offset_dwords == 0);
 
-    BEGIN_CS(10);
+    BEGIN_CS(14);
+    OUT_CS_REG(R300_GA_COLOR_CONTROL,
+            r300_provoking_vertex_fixes(r300, mode));
+    OUT_CS_REG(R300_VAP_VF_MIN_VTX_INDX, minIndex);
     OUT_CS_REG(R300_VAP_VF_MAX_VTX_INDX, maxIndex);
     OUT_CS_PKT3(R300_PACKET3_3D_DRAW_INDX_2, 0);
     if (indexSize == 4) {
@@ -177,13 +232,24 @@ boolean r300_draw_range_elements(struct pipe_context* pipe,
         return FALSE;
     }
 
+    if (r300_nothing_to_draw(r300)) {
+        return TRUE;
+    }
+
     r300_update_derived_state(r300);
 
     if (!r300_setup_vertex_buffers(r300)) {
         return FALSE;
     }
 
-    setup_index_buffer(r300, indexBuffer, indexSize);
+    if (!r300->winsys->add_buffer(r300->winsys, indexBuffer,
+                                  RADEON_GEM_DOMAIN_GTT, 0)) {
+        return FALSE;
+    }
+
+    if (!r300->winsys->validate(r300->winsys)) {
+        return FALSE;
+    }
 
     r300_emit_dirty_state(r300);
 
@@ -218,6 +284,10 @@ boolean r300_draw_arrays(struct pipe_context* pipe, unsigned mode,
         return FALSE;
     }
 
+    if (r300_nothing_to_draw(r300)) {
+        return TRUE;
+    }
+
     r300_update_derived_state(r300);
 
     if (!r300_setup_vertex_buffers(r300)) {
@@ -251,6 +321,10 @@ boolean r300_swtcl_draw_arrays(struct pipe_context* pipe,
         return FALSE;
     }
 
+    if (r300_nothing_to_draw(r300)) {
+        return TRUE;
+    }
+
     for (i = 0; i < r300->vertex_buffer_count; i++) {
         void* buf = pipe_buffer_map(pipe->screen,
                                     r300->vertex_buffer[i].buffer,
@@ -292,6 +366,10 @@ boolean r300_swtcl_draw_range_elements(struct pipe_context* pipe,
         return FALSE;
     }
 
+    if (r300_nothing_to_draw(r300)) {
+        return TRUE;
+    }
+
     for (i = 0; i < r300->vertex_buffer_count; i++) {
         void* buf = pipe_buffer_map(pipe->screen,
                                     r300->vertex_buffer[i].buffer,