Fix Chromoting Mac to work with multiple monitors.

remoting/host/capturer_mac.cc

 // Copyright (c) 2011 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "remoting/host/capturer.h"
 
 #include <ApplicationServices/ApplicationServices.h>
 #include <OpenGL/CGLMacro.h>
 #include <OpenGL/OpenGL.h>
 
@@ skipping 359 matching lines @@
     // the invalid region from the previous capture in the current buffer.
     // TODO(hclam): We can reduce the amount of copying here by subtracting
     // |capturer_helper_|s region from |last_invalid_region_|.
     // http://crbug.com/92354
 
     // Since the image obtained from OpenGL is upside-down, need to do some
     // magic here to copy the correct rectangle.
     const int y_offset = (buffer_height - 1) * buffer.bytes_per_row();
     for(SkRegion::Iterator i(last_invalid_region_); !i.done(); i.next()) {
       SkIRect copy_rect = i.rect();
-      copy_rect.intersect(clip_rect);
-      CopyRect(last_buffer_ + y_offset,
-               -buffer.bytes_per_row(),
-               buffer.ptr() + y_offset,
-               -buffer.bytes_per_row(),
-               4,  // Bytes for pixel for RGBA.
-               copy_rect);
+      if (copy_rect.intersect(clip_rect)) {
+        CopyRect(last_buffer_ + y_offset,
+                 -buffer.bytes_per_row(),
+                 buffer.ptr() + y_offset,
+                 -buffer.bytes_per_row(),
+                 4,  // Bytes for pixel for RGBA.
+                 copy_rect);
+      }
     }
   }
   last_buffer_ = buffer.ptr();
   last_invalid_region_ = region;
 
   CGLContextObj CGL_MACRO_CONTEXT = cgl_context_;
   glBindBufferARB(GL_PIXEL_PACK_BUFFER_ARB, pixel_buffer_object_.get());
   glReadPixels(0, 0, buffer_width, buffer_height, GL_BGRA, GL_UNSIGNED_BYTE, 0);
   GLubyte* ptr = static_cast<GLubyte*>(
       glMapBufferARB(GL_PIXEL_PACK_BUFFER_ARB, GL_READ_ONLY_ARB));
   if (ptr == NULL) {
     // If the buffer can't be mapped, assume that it's no longer valid and
     // release it.
     pixel_buffer_object_.Release();
   } else {
     // Copy only from the dirty rects. Since the image obtained from OpenGL is
     // upside-down we need to do some magic here to copy the correct rectangle.
     const int y_offset = (buffer_height - 1) * buffer.bytes_per_row();
     for(SkRegion::Iterator i(region); !i.done(); i.next()) {
       SkIRect copy_rect = i.rect();
-      copy_rect.intersect(clip_rect);
-      CopyRect(ptr + y_offset,
-         -buffer.bytes_per_row(),
-         buffer.ptr() + y_offset,
-         -buffer.bytes_per_row(),
-         4,  // Bytes for pixel for RGBA.
-         copy_rect);
+      if (copy_rect.intersect(clip_rect)) {
+        CopyRect(ptr + y_offset,
+           -buffer.bytes_per_row(),
+           buffer.ptr() + y_offset,
+           -buffer.bytes_per_row(),
+           4,  // Bytes for pixel for RGBA.
+           copy_rect);
+      }
     }
   }
   if (!glUnmapBufferARB(GL_PIXEL_PACK_BUFFER_ARB)) {
     // If glUnmapBuffer returns false, then the contents of the data store are
     // undefined. This might be because the screen mode has changed, in which
     // case it will be recreated in ScreenConfigurationChanged, but releasing
     // the object here is the best option. Capturing will fall back on
     // GlBlitSlow until such time as the pixel buffer object is recreated.
     pixel_buffer_object_.Release();
   }
@@ skipping 29 matching lines @@
   CGDirectDisplayID main_display = CGMainDisplayID();
   uint8* display_base_address =
       reinterpret_cast<uint8*>(CGDisplayBaseAddress(main_display));
   int src_bytes_per_row = CGDisplayBytesPerRow(main_display);
   int src_bytes_per_pixel = CGDisplayBitsPerPixel(main_display) / 8;
   // TODO(hclam): We can reduce the amount of copying here by subtracting
   // |capturer_helper_|s region from |last_invalid_region_|.
   // http://crbug.com/92354
   for(SkRegion::Iterator i(region); !i.done(); i.next()) {
     SkIRect copy_rect = i.rect();
-    copy_rect.intersect(clip_rect);
-    CopyRect(display_base_address,
-             src_bytes_per_row,
-             buffer.ptr(),
-             buffer.bytes_per_row(),
-             src_bytes_per_pixel,
-             copy_rect);
+    if (copy_rect.intersect(clip_rect)) {
+      CopyRect(display_base_address,
+               src_bytes_per_row,
+               buffer.ptr(),
+               buffer.bytes_per_row(),
+               src_bytes_per_pixel,
+               copy_rect);
+    }
   }
 }
 
 const gfx::Size& CapturerMac::size_most_recent() const {
   return helper_.size_most_recent();
 }
 
 void CapturerMac::ScreenRefresh(CGRectCount count, const CGRect *rect_array) {
   SkIRect skirect_array[count];
   for (CGRectCount i = 0; i < count; ++i) {
@@ skipping 65 matching lines @@
 Capturer* Capturer::Create() {
   CapturerMac* capturer = new CapturerMac();
   if (!capturer->Init()) {
     delete capturer;
     capturer = NULL;
   }
   return capturer;
 }
 
 }  // namespace remoting