From 42742a56efbe4726555339a0e1a7858f8563a8f0 Mon Sep 17 00:00:00 2001
From: "adam.fedor" <adam.fedor@gmail.com>
Date: Mon, 12 Jun 2017 07:32:02 -0700
Subject: [PATCH] Fall-back to OpenGL renderer if mac hardware doesn't support
 Metal

BUG=webrtc:7782

Review-Url: https://codereview.webrtc.org/2927983002
Cr-Commit-Position: refs/heads/master@{#18539}
---
 .../examples/objc/AppRTCMobile/mac/APPRTCViewController.m  | 7 ++++---
 .../sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m   | 2 +-
 .../sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h  | 2 +-
 3 files changed, 6 insertions(+), 5 deletions(-)

diff --git a/webrtc/examples/objc/AppRTCMobile/mac/APPRTCViewController.m b/webrtc/examples/objc/AppRTCMobile/mac/APPRTCViewController.m
index c23e0d59cd..d8ee1413f3 100644
--- a/webrtc/examples/objc/AppRTCMobile/mac/APPRTCViewController.m
+++ b/webrtc/examples/objc/AppRTCMobile/mac/APPRTCViewController.m
@@ -221,10 +221,12 @@ static NSUInteger const kBottomViewHeight = 200;
 // If not we're providing sensible default.
 #pragma clang diagnostic push
 #pragma clang diagnostic ignored "-Wpartial-availability"
-  if ([RTCMTLNSVideoView class]) {
+  if ([RTCMTLNSVideoView class] && [RTCMTLNSVideoView isMetalAvailable]) {
     _remoteVideoView = [[RTCMTLNSVideoView alloc] initWithFrame:NSZeroRect];
     _localVideoView = [[RTCMTLNSVideoView alloc] initWithFrame:NSZeroRect];
-  } else {
+  }
+#pragma clang diagnostic pop
+  if (_remoteVideoView == nil) {
     NSOpenGLPixelFormatAttribute attributes[] = {
       NSOpenGLPFADoubleBuffer,
       NSOpenGLPFADepthSize, 24,
@@ -245,7 +247,6 @@ static NSUInteger const kBottomViewHeight = 200;
     local.delegate = self;
     _localVideoView = local;
   }
-#pragma clang diagnostic pop
 
   [_remoteVideoView setTranslatesAutoresizingMaskIntoConstraints:NO];
   [self addSubview:_remoteVideoView];
diff --git a/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m b/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m
index dd41393267..ff23bc6e6e 100644
--- a/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m
+++ b/webrtc/sdk/objc/Framework/Classes/Metal/RTCMTLNSVideoView.m
@@ -50,7 +50,7 @@
 #pragma mark - Private
 
 + (BOOL)isMetalAvailable {
-  return YES;
+  return [MTLCopyAllDevices() count] > 0;
 }
 
 - (void)configure {
diff --git a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h
index d9f4164a8b..4990e2529e 100644
--- a/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h
+++ b/webrtc/sdk/objc/Framework/Headers/WebRTC/RTCMTLNSVideoView.h
@@ -13,5 +13,5 @@
 
 NS_AVAILABLE_MAC(10.11)
 @interface RTCMTLNSVideoView : NSView<RTCVideoRenderer>
-
++ (BOOL)isMetalAvailable;
 @end