X-Git-Url: https://git.libre-soc.org/?a=blobdiff_plain;f=src%2Fmesa%2Fstate_tracker%2Fst_atom_stipple.c;h=b3e0dc7f1b085486dfe54b97a558d8a70d4dbcb0;hb=8b881ad1c3d9dd3c96afbdbb608a7240d40e9c92;hp=f395930ab40343bc2e89f9686bf194300a69ad96;hpb=61d3a66456852642ed8fdc1106dc0012e4b89779;p=mesa.git

diff --git a/src/mesa/state_tracker/st_atom_stipple.c b/src/mesa/state_tracker/st_atom_stipple.c
index f395930ab40..b3e0dc7f1b0 100644
--- a/src/mesa/state_tracker/st_atom_stipple.c
+++ b/src/mesa/state_tracker/st_atom_stipple.c
@@ -33,30 +33,61 @@
   */
  
 
+#include <assert.h>
+
 #include "st_context.h"
 #include "st_atom.h"
 #include "pipe/p_context.h"
 #include "pipe/p_defines.h"
 
 
+/**
+ * OpenGL's polygon stipple is indexed with window coordinates in which
+ * the origin (0,0) is the lower-left corner of the window.
+ * With Gallium, the origin is the upper-left corner of the window.
+ * To convert GL's polygon stipple to what gallium expects we need to
+ * invert the pattern vertically and rotate the stipple rows according
+ * to the window height.
+ */
+static void
+invert_stipple(GLuint dest[32], const GLuint src[32], GLuint winHeight)
+{
+   GLuint i;
+
+   for (i = 0; i < 32; i++) {
+      dest[i] = src[(winHeight - 1 - i) & 0x1f];
+   }
+}
+
+
+
 static void 
 update_stipple( struct st_context *st )
 {
-   const GLuint sz = sizeof(st->state.poly_stipple.stipple);
-   assert(sz == sizeof(st->ctx->PolygonStipple));
+   const struct gl_context *ctx = st->ctx;
+   const GLuint sz = sizeof(st->state.poly_stipple);
+   assert(sz == sizeof(ctx->PolygonStipple));
 
-   if (memcmp(&st->state.poly_stipple.stipple, st->ctx->PolygonStipple, sz)) {
+   if (memcmp(st->state.poly_stipple, ctx->PolygonStipple, sz)) {
       /* state has changed */
-      memcpy(st->state.poly_stipple.stipple, st->ctx->PolygonStipple, sz);
-      st->pipe->set_polygon_stipple(st->pipe, &st->state.poly_stipple);
+      struct pipe_poly_stipple newStipple;
+
+      memcpy(st->state.poly_stipple, ctx->PolygonStipple, sz);
+
+      invert_stipple(newStipple.stipple, ctx->PolygonStipple,
+                     ctx->DrawBuffer->Height);
+
+      st->pipe->set_polygon_stipple(st->pipe, &newStipple);
    }
 }
 
 
+/** Update the stipple when the pattern or window height changes */
 const struct st_tracked_state st_update_polygon_stipple = {
    "st_update_polygon_stipple",				/* name */
    {							/* dirty */
-      (_NEW_POLYGONSTIPPLE),				/* mesa */
+      (_NEW_POLYGONSTIPPLE |
+       _NEW_BUFFERS),					/* mesa */
       0,						/* st */
    },
    update_stipple					/* update */