Add Paul's MSAA patchubuntu-precise

3 files changed, 62 insertions, 0 deletions

diff --git a/debian/changelog b/debian/changelog
index e3c6acd9f6..b4ee166a01 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,3 +1,10 @@
+mesa (9.1~git20120910.e81ee67b-5) precise; urgency=low
+
+  [ Jordan Justen ]
+  * Add Paul's MSAA patch
+
+ -- Jordan Justen <jljusten@gmail.com>  Mon, 10 Sep 2012 15:42:40 -0700
+
 mesa (9.1~git20120910.e81ee67b-4) precise; urgency=low
 
   [ Jordan Justen ]
diff --git a/debian/patches/16-mesa-msaa--Allow-X-and-Y-flips-in-multisampled-blits.patch b/debian/patches/16-mesa-msaa--Allow-X-and-Y-flips-in-multisampled-blits.patch
new file mode 100644
index 0000000000..c810a9ebe0
--- /dev/null
+++ b/debian/patches/16-mesa-msaa--Allow-X-and-Y-flips-in-multisampled-blits.patch
@@ -0,0 +1,54 @@
+To: mesa-dev@lists.freedesktop.org
+Date: Wed,  5 Sep 2012 16:22:56 -0700
+Subject: [Mesa-dev] [PATCH] mesa/msaa: Allow X and Y flips in multisampled
+	blits.
+
+From the GL 4.3 spec, section 18.3.1 "Blitting Pixel Rectangles":
+
+    If SAMPLE_BUFFERS for either the read framebuffer or draw
+    framebuffer is greater than zero, no copy is performed and an
+    INVALID_OPERATION error is generated if the dimensions of the
+    source and destination rectangles provided to BlitFramebuffer are
+    not identical, or if the formats of the read and draw framebuffers
+    are not identical.
+
+It is not clear from the spec whether "dimensions" should mean both
+sign and magnitude, or just magnitude.
+
+Previously, Mesa interpreted "dimensions" as meaning both sign and
+magnitude, so any multisampled blit that attempted to flip the image
+in the X and/or Y direction would fail.
+
+However, Y flips are likely to be commonplace in OpenGL applications
+that have been ported from DirectX applications, as a result of the
+fact that DirectX and OpenGL differ in their orientation of the Y
+axis.  Furthermore, at least one commercial driver (nVidia) permits Y
+filps, and L4D2 relies on them being permitted.  So it seems prudent
+for Mesa to permit them.
+
+This patch changes Mesa to allow both X and Y flips, since there is no
+language in the spec to indicate that X and Y flips should be treated
+differently.
+
+NOTE: This is a candidate for stable release branches.
+---
+ src/mesa/main/fbobject.c |    4 ++--
+ 1 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/src/mesa/main/fbobject.c b/src/mesa/main/fbobject.c
+index 59a5ec3..abc9d83 100644
+--- a/src/mesa/main/fbobject.c
++++ b/src/mesa/main/fbobject.c
+@@ -2979,8 +2979,8 @@ _mesa_BlitFramebufferEXT(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
+    /* extra checks for multisample copies... */
+    if (readFb->Visual.samples > 0 || drawFb->Visual.samples > 0) {
+       /* src and dest region sizes must be the same */
+-      if (srcX1 - srcX0 != dstX1 - dstX0 ||
+-          srcY1 - srcY0 != dstY1 - dstY0) {
++      if (abs(srcX1 - srcX0) != abs(dstX1 - dstX0) ||
++          abs(srcY1 - srcY0) != abs(dstY1 - dstY0)) {
+          _mesa_error(ctx, GL_INVALID_OPERATION,
+                 "glBlitFramebufferEXT(bad src/dst multisample region sizes)");
+          return;
+-- 
+1.7.7.6
diff --git a/debian/patches/series b/debian/patches/series
index 0d68a36094..d983f91a2e 100644
--- a/debian/patches/series
+++ b/debian/patches/series
@@ -8,3 +8,4 @@
 13-llvm-config-pick-a-version.diff
 14-fix-osmesa-build.diff
 15-fix-llvmpipe-test-linking.diff
+16-mesa-msaa--Allow-X-and-Y-flips-in-multisampled-blits.patch