Mesa (mesa_7_5_branch): mesa: Reverse s8z24 into z24s8 as required by EXT_packed_depth_stencil.

[Jose Fonseca]

Module: Mesa
Branch: mesa_7_5_branch
Commit: 337f559cd2d98a858719cb963450fef2256e83f7
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=337f559cd2d98a858719cb963450fef2256e83f7

Author: José Fonseca <jfonseca at vmware.com>
Date:   Wed Jun 10 21:29:25 2009 +0100

mesa: Reverse s8z24 into z24s8 as required by EXT_packed_depth_stencil.

Actually, after spotting this problem, I realized this is unreachable
code. However don't bother to enable this fast path now, given the normal
path is working just fine.

---

 src/mesa/state_tracker/st_cb_readpixels.c |    9 +++++++--
 1 files changed, 7 insertions(+), 2 deletions(-)

diff --git a/src/mesa/state_tracker/st_cb_readpixels.c b/src/mesa/state_tracker/st_cb_readpixels.c
index 86baf3d..ccf1a0b 100644
--- a/src/mesa/state_tracker/st_cb_readpixels.c
+++ b/src/mesa/state_tracker/st_cb_readpixels.c
@@ -445,11 +445,16 @@ st_readpixels(GLcontext *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
             }
          }
          else {
-            /* untested, but simple: */
+            /* XXX: unreachable code -- should be before st_read_stencil_pixels */
             assert(format == GL_DEPTH_STENCIL_EXT);
             for (i = 0; i < height; i++) {
+               GLuint *zshort = (GLuint *)dst;
                pipe_get_tile_raw(trans, 0, y, width, 1, dst, 0);
                y += yStep;
+               /* Reverse into 24/8 */
+               for (j = 0; j < width; j++) {
+                  zshort[j] = (zshort[j] << 8) | (zshort[j] >> 24);
+               }
                dst += dstStride;
             }
          }
@@ -472,7 +477,7 @@ st_readpixels(GLcontext *ctx, GLint x, GLint y, GLsizei width, GLsizei height,
             }
          }
          else {
-            /* untested, but simple: */
+            /* XXX: unreachable code -- should be before st_read_stencil_pixels */
             assert(format == GL_DEPTH_STENCIL_EXT);
             for (i = 0; i < height; i++) {
                pipe_get_tile_raw(trans, 0, y, width, 1, dst, 0);