Add conditional-free implementation (disabled, not tested)

diff --git a/src/mesa/pipe/softpipe/sp_quad_stipple.c b/src/mesa/pipe/softpipe/sp_quad_stipple.c
index e77bbb8..928771e 100644 (file)
--- a/src/mesa/pipe/softpipe/sp_quad_stipple.c
+++ b/src/mesa/pipe/softpipe/sp_quad_stipple.c
@@ -23,13 +23,15 @@ stipple_quad(struct quad_stage *qs, struct quad_header *quad)
    const GLint row0 = quad->y0 % 32;
    const GLuint stipple0 = softpipe->poly_stipple.stipple[row0];
    const GLuint stipple1 = softpipe->poly_stipple.stipple[row0 + 1];
+
+   /* XXX this should be acheivable without conditionals */
+#if 1
    GLbitfield mask = 0x0;
 
-   /* XXX this could be optimize a bit to use just two conditionals */
    if ((1 << col0) & stipple0)
       mask |= MASK_BOTTOM_LEFT;
 
-   if ((2 << col0) & stipple0)
+   if ((2 << col0) & stipple0) /* note: col0 <= 30 */
       mask |= MASK_BOTTOM_RIGHT;
 
    if ((1 << col0) & stipple1)
@@ -39,6 +41,13 @@ stipple_quad(struct quad_stage *qs, struct quad_header *quad)
       mask |= MASK_TOP_RIGHT;
 
    quad->mask &= mask;
+#else
+   /* XXX there may be a better way to lay out the stored stipple
+    * values to further simplify this computation.
+    */
+   quad->mask &= (((stipple0 >> col0) & 0x3) | 
+                 (((stipple1 >> col0) & 0x3) << 2));
+#endif
 
    if (quad->mask)
       qs->next->run(qs->next, quad);