Mac: Only allow NSOpenGLContext displaying on the main display

ui/accelerated_widget_mac/io_surface_ns_gl_surface.mm

 // Copyright 2015 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 "ui/accelerated_widget_mac/io_surface_ns_gl_surface.h"
 
+#include <OpenGL/CGLRenderers.h>
 #include <OpenGL/GL.h>
 
 #include "base/callback_helpers.h"
+#include "base/command_line.h"
 #include "base/mac/bind_objc_block.h"
+#include "base/mac/mac_util.h"
 #include "base/mac/sdk_forward_declarations.h"
 #include "base/message_loop/message_loop.h"
 #include "base/trace_event/trace_event.h"
 #include "ui/base/cocoa/animation_utils.h"
+#include "ui/base/ui_base_switches.h"
 #include "ui/gfx/geometry/dip_util.h"
 #include "ui/gfx/geometry/rect.h"
 #include "ui/gl/gpu_switching_manager.h"
 
 namespace ui {
 
 IOSurfaceNSGLSurface* IOSurfaceNSGLSurface::Create(
-    IOSurfaceNSGLSurfaceClient* client, NSView* view) {
-  scoped_refptr<IOSurfaceTexture> iosurface = IOSurfaceTexture::Create(false);
+    IOSurfaceNSGLSurfaceClient* client,
+    NSView* view,
+    bool needs_gl_finish_workaround) {
+  scoped_refptr<IOSurfaceTexture> iosurface =
+      IOSurfaceTexture::Create(needs_gl_finish_workaround, true);
   if (!iosurface)
     return NULL;
 
   std::vector<NSOpenGLPixelFormatAttribute> attribs;
   attribs.push_back(NSOpenGLPFAColorSize);
   attribs.push_back(24);
   attribs.push_back(NSOpenGLPFAAlphaSize);
   attribs.push_back(8);
   attribs.push_back(NSOpenGLPFAAccelerated);
   if (ui::GpuSwitchingManager::GetInstance()->SupportsDualGpus())
     attribs.push_back(NSOpenGLPFAAllowOfflineRenderers);
   attribs.push_back(0);
   base::scoped_nsobject<NSOpenGLPixelFormat> pixel_format(
       [[NSOpenGLPixelFormat alloc] initWithAttributes:&attribs.front()]);
   if (!pixel_format) {
     LOG(ERROR) << "Failed to create pixel format object.";
     return NULL;
   }
 
   base::scoped_nsobject<NSOpenGLContext> ns_gl_context(
       [[NSOpenGLContext alloc] initWithFormat:pixel_format shareContext:nil]);
   if (!ns_gl_context) {
     LOG(ERROR) << "Failed to create context object.";
     return NULL;
   }
 
-  return new IOSurfaceNSGLSurface(client, view, ns_gl_context, iosurface);
+  return new IOSurfaceNSGLSurface(
+      client, view, needs_gl_finish_workaround, ns_gl_context, iosurface);
 }
 
 IOSurfaceNSGLSurface::IOSurfaceNSGLSurface(
     IOSurfaceNSGLSurfaceClient* client,
     NSView* view,
+    bool needs_gl_finish_workaround,
     base::scoped_nsobject<NSOpenGLContext> ns_gl_context,
     scoped_refptr<ui::IOSurfaceTexture> iosurface)
     : client_(client), view_(view), iosurface_(iosurface),
       ns_gl_context_(ns_gl_context), contents_scale_factor_(1),
       pending_draw_exists_(false) {
   [[view_ layer] setContentsGravity:kCAGravityTopLeft];
 }
 
 IOSurfaceNSGLSurface::~IOSurfaceNSGLSurface() {
   DoPendingDrawIfNeeded();
   [ns_gl_context_ makeCurrentContext];
   iosurface_ = NULL;
   [NSOpenGLContext clearCurrentContext];
   [ns_gl_context_ clearDrawable];
 
   ScopedCAActionDisabler disabler;
   [[view_ layer] setContents:nil];
 }
 
 bool IOSurfaceNSGLSurface::GotFrame(IOSurfaceID io_surface_id,
                                     gfx::Size frame_pixel_size,
                                     float frame_scale_factor,
                                     gfx::Rect pixel_damage_rect) {
+  TRACE_EVENT0("ui", "IOSurfaceNSGLSurface::GotFrame");
   pending_draw_exists_ = true;
   pending_draw_damage_rect_.Union(pixel_damage_rect);
 
   // If the OpenGL framebuffer does not match the frame in scale factor or
   // pixel size, then re-latch them. Note that they will latch to the layer's
   // bounds, which will not necessarily match the frame's pixel size.
   if (!iosurface_->IsUpToDate(io_surface_id, frame_pixel_size) ||
       [ns_gl_context_ view] != view_ ||
       frame_pixel_size != contents_pixel_size_ ||
       frame_scale_factor != contents_scale_factor_) {
@@ skipping 42 matching lines @@
     glFlush();
     [NSOpenGLContext clearCurrentContext];
   }
 
   pending_draw_exists_ = false;
   pending_draw_damage_rect_ = gfx::Rect();
 
   client_->IOSurfaceNSGLSurfaceDidDrawFrame();
 }
 
-};
+int IOSurfaceNSGLSurface::GetRendererID() {
+  GLint current_renderer_id = -1;
+  CGLContextObj cgl_context = static_cast<CGLContextObj>(

[Andre, 2015/06/10 05:23:39]

Why do you need this cast?

[ccameron, 2015/06/10 21:39:51]

-[NSOpenGLContext CGLContextObj] returns a void*, for unclear reasons. I was
surprised by this, too.

+      [ns_gl_context_ CGLContextObj]);
+  if (CGLGetParameter(cgl_context,
+                      kCGLCPCurrentRendererID,
+                      &current_renderer_id) == kCGLNoError) {
+    return current_renderer_id & kCGLRendererIDMatchingMask;
+  }
+  return -1;
+}
+
+// static
+bool IOSurfaceNSGLSurface::CanUseNSGLSurfaceForView(NSView* view) {
+  // This must be explicitly enabled at the command line.
+  static bool use_ns_gl_surfaces =
+      base::CommandLine::ForCurrentProcess()->HasSwitch(
+          switches::kEnableNSGLSurfaces);
+  if (!use_ns_gl_surfaces)
+    return false;
+
+  // Do not attempt this before 10.9. The power savings are not worth the
+  // stability risk and testing burden.
+  if (!base::mac::IsOSMavericksOrLater())
+    return false;
+
+  // If the NSView being attached to the NSOpenGLContext is not on the main
+  // monitor, then, due to an OS X bug, the IOSurface will be thrashed,
+  // resulting in hangs of 50 msec or more.
+  CGDirectDisplayID main_display = CGMainDisplayID();
+  NSScreen* screen = [[view window] screen];
+  NSDictionary* screen_description = [screen deviceDescription];
+  NSNumber* screen_number = [screen_description objectForKey:@"NSScreenNumber"];
+  CGDirectDisplayID display_id = [screen_number unsignedIntValue];
+  if (display_id != main_display)
+    return false;
+
+  return true;
+}
+
+}  // namespace ui