commit 9a8d366a992691e6e4ab45d985733d58ff9bbc62
author Corentin Wallez <cwallez@chromium.org> Thu Sep 22 12:18:29 2016 -0400
committer Commit Bot <commit-bot@chromium.org> Tue Sep 27 23:15:49 2016 +0000
tree f24ef5bf2d443233359a3b0ce8cff92d9b5fb9d2
parent 0f40d235e22008e9ea12b9fb8597dc144f6cbc2c

FramebufferGL: add readPixels workarounds

Implements workarounds for:
 - The pack state making rows overlap in memory, which causes crashes on
   some drivers.
 - The driver adding an extra last row padding when checking if the
   pixel pack buffer is large enough for the readPixels.

BUG=angleproject:1512

Change-Id: I120ff58649bb523e8b01da6ef03d8fcadaf076b2
Reviewed-on: https://chromium-review.googlesource.com/388029
Commit-Queue: Corentin Wallez <cwallez@chromium.org>
Reviewed-by: Geoff Lang <geofflang@chromium.org>

src/libANGLE/Context.cpp

diff --git a/src/libANGLE/Context.cpp b/src/libANGLE/Context.cpp
index 1ed648c..755f12b 100644
--- a/src/libANGLE/Context.cpp
+++ b/src/libANGLE/Context.cpp
@@ -2569,6 +2569,11 @@
                          GLenum type,
                          GLvoid *pixels)
 {
+    if (width == 0 || height == 0)
+    {
+        return;
+    }
+
     syncStateForReadPixels();
 
     Framebuffer *framebufferObject = mGLState.getReadFramebuffer();
@@ -2607,6 +2612,11 @@
                                 GLsizei width,
                                 GLsizei height)
 {
+    if (width == 0 || height == 0)
+    {
+        return;
+    }
+
     // Only sync the read FBO
     mGLState.syncDirtyObject(GL_READ_FRAMEBUFFER);
 
@@ -2629,6 +2639,11 @@
                                 GLsizei width,
                                 GLsizei height)
 {
+    if (width == 0 || height == 0)
+    {
+        return;
+    }
+
     // Only sync the read FBO
     mGLState.syncDirtyObject(GL_READ_FRAMEBUFFER);