llvmpipe: scale up bounding box planes to subpixel precision

Otherwise some planes we get in rasterization have subpixel precision, others
not. Doesn't matter so far, but will soon. (OpenGL actually supports viewports
with subpixel accuracy, so could even do bounding box calcs with that).

Reviewed-by: Brian Paul <brianp@vmware.com>
Reviewed-by: Jose Fonseca <jfonseca@vmware.com>

diff --git a/src/gallium/drivers/llvmpipe/lp_setup_line.c b/src/gallium/drivers/llvmpipe/lp_setup_line.c
index a0de599..f425825 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_setup_line.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup_line.c
@@ -713,24 +713,24 @@ try_setup_line( struct lp_setup_context *setup,
       const struct u_rect *scissor =
          &setup->scissors[viewport_index];
 
-      plane[4].dcdx = -1;
+      plane[4].dcdx = -1 << 8;
       plane[4].dcdy = 0;
-      plane[4].c = 1-scissor->x0;
-      plane[4].eo = 1;
+      plane[4].c = (1-scissor->x0) << 8;
+      plane[4].eo = 1 << 8;
 
-      plane[5].dcdx = 1;
+      plane[5].dcdx = 1 << 8;
       plane[5].dcdy = 0;
-      plane[5].c = scissor->x1+1;
+      plane[5].c = (scissor->x1+1) << 8;
       plane[5].eo = 0;
 
       plane[6].dcdx = 0;
-      plane[6].dcdy = 1;
-      plane[6].c = 1-scissor->y0;
-      plane[6].eo = 1;
+      plane[6].dcdy = 1 << 8;
+      plane[6].c = (1-scissor->y0) << 8;
+      plane[6].eo = 1 << 8;
 
       plane[7].dcdx = 0;
-      plane[7].dcdy = -1;
-      plane[7].c = scissor->y1+1;
+      plane[7].dcdy = -1 << 8;
+      plane[7].c = (scissor->y1+1) << 8;
       plane[7].eo = 0;
    }
 

diff --git a/src/gallium/drivers/llvmpipe/lp_setup_point.c b/src/gallium/drivers/llvmpipe/lp_setup_point.c
index 14c389f..ddb6f0e 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_setup_point.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup_point.c
@@ -492,24 +492,24 @@ try_setup_point( struct lp_setup_context *setup,
    {
       struct lp_rast_plane *plane = GET_PLANES(point);
 
-      plane[0].dcdx = -1;
+      plane[0].dcdx = -1 << 8;
       plane[0].dcdy = 0;
-      plane[0].c = 1-bbox.x0;
-      plane[0].eo = 1;
+      plane[0].c = (1-bbox.x0) << 8;
+      plane[0].eo = 1 << 8;
 
-      plane[1].dcdx = 1;
+      plane[1].dcdx = 1 << 8;
       plane[1].dcdy = 0;
-      plane[1].c = bbox.x1+1;
+      plane[1].c = (bbox.x1+1) << 8;
       plane[1].eo = 0;
 
       plane[2].dcdx = 0;
-      plane[2].dcdy = 1;
-      plane[2].c = 1-bbox.y0;
-      plane[2].eo = 1;
+      plane[2].dcdy = 1 << 8;
+      plane[2].c = (1-bbox.y0) << 8;
+      plane[2].eo = 1 << 8;
 
       plane[3].dcdx = 0;
-      plane[3].dcdy = -1;
-      plane[3].c = bbox.y1+1;
+      plane[3].dcdy = -1 << 8;
+      plane[3].c = (bbox.y1+1) << 8;
       plane[3].eo = 0;
    }
 

diff --git a/src/gallium/drivers/llvmpipe/lp_setup_tri.c b/src/gallium/drivers/llvmpipe/lp_setup_tri.c
index 6914882..4925da9 100644 (file)
--- a/src/gallium/drivers/llvmpipe/lp_setup_tri.c
+++ b/src/gallium/drivers/llvmpipe/lp_setup_tri.c
@@ -676,24 +676,24 @@ do_triangle_ccw(struct lp_setup_context *setup,
    if (nr_planes == 7) {
       const struct u_rect *scissor = &setup->scissors[viewport_index];
 
-      plane[3].dcdx = -1;
+      plane[3].dcdx = -1 << 8;
       plane[3].dcdy = 0;
-      plane[3].c = 1-scissor->x0;
-      plane[3].eo = 1;
+      plane[3].c = (1-scissor->x0) << 8;
+      plane[3].eo = 1 << 8;
 
-      plane[4].dcdx = 1;
+      plane[4].dcdx = 1 << 8;
       plane[4].dcdy = 0;
-      plane[4].c = scissor->x1+1;
+      plane[4].c = (scissor->x1+1) << 8;
       plane[4].eo = 0;
 
       plane[5].dcdx = 0;
-      plane[5].dcdy = 1;
-      plane[5].c = 1-scissor->y0;
-      plane[5].eo = 1;
+      plane[5].dcdy = 1 << 8;
+      plane[5].c = (1-scissor->y0) << 8;
+      plane[5].eo = 1 << 8;
 
       plane[6].dcdx = 0;
-      plane[6].dcdy = -1;
-      plane[6].c = scissor->y1+1;
+      plane[6].dcdy = -1 << 8;
+      plane[6].c = (scissor->y1+1) << 8;
       plane[6].eo = 0;
    }