From: Roland Scheidegger <sroland@vmware.com>
Date: Sun, 3 Jan 2016 00:13:45 +0000 (+0100)
Subject: llvmpipe: scale up bounding box planes to subpixel precision
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=16530fdc82cde61495c66abe704e88d7752dfdbf;p=mesa.git

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 a0de599c9c6..f425825fc2a 100644
--- 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 14c389f7ce0..ddb6f0e73b0 100644
--- 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 6914882e637..4925da98bdb 100644
--- 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;
    }