commit e49452de1f0b14a526d528274d6e0d9ffc1e3d4a
author Kári Tristan Helgason <kthelgason@webrtc.org> Tue Apr 10 08:38:43 2018
committer Commit Bot <commit-bot@chromium.org> Tue Apr 10 13:24:25 2018
tree 60c407d63b964eb1927dd85f3a5b75d44486f816
parent 07f80cc3936b3d68c668a942ef1089a5ba12bf9e

Reland "Improve thread-safety of MTL Renderer."

This is a reland of a8f13ccad400eb8ff84a379042c0595951ca9658

Original change's description:
> Improve thread-safety of MTL Renderer.
> 
> Bug: b/77579859
> Change-Id: I427d0f41593155dc5cbf98a09d7ec826497b803c
> Reviewed-on: https://webrtc-review.googlesource.com/67040
> Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
> Reviewed-by: Anders Carlsson <andersc@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#22795}

Bug: b/77579859
Change-Id: I9582cffaae5e241fdb4e41a2a5892738b7246e39
Reviewed-on: https://webrtc-review.googlesource.com/68960
Reviewed-by: Anders Carlsson <andersc@webrtc.org>
Commit-Queue: Kári Helgason <kthelgason@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#22806}

sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.mm

diff --git a/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.mm b/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.mm
index 079b5fb..6de9c34 100644
--- a/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.mm
+++ b/sdk/objc/Framework/Classes/Metal/RTCMTLNV12Renderer.mm
@@ -18,6 +18,7 @@
 #import "WebRTC/RTCVideoFrameBuffer.h"
 
 #import "RTCMTLRenderer+Private.h"
+#include "rtc_base/checks.h"
 
 #define MTL_STRINGIFY(s) @ #s
 
@@ -85,6 +86,7 @@
 }
 
 - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame {
+  RTC_DCHECK([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]);
   [super setupTexturesForFrame:frame];
   CVPixelBufferRef pixelBuffer = ((RTCCVPixelBuffer *)frame.buffer).pixelBuffer;
 

sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m

diff --git a/sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m b/sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m
index 0e17777..5334edb 100644
--- a/sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m
+++ b/sdk/objc/Framework/Classes/Metal/RTCMTLVideoView.m
@@ -105,12 +105,12 @@
 
 - (void)drawInMTKView:(nonnull MTKView *)view {
   NSAssert(view == self.metalView, @"Receiving draw callbacks from foreign instance.");
-  if (!self.videoFrame) {
+  RTCVideoFrame *videoFrame = self.videoFrame;
+  if (!videoFrame) {
     return;
   }
 
-  id<RTCMTLRenderer> renderer = nil;
-  if ([self.videoFrame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
+  if ([videoFrame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
     if (!self.rendererNV12) {
       self.rendererNV12 = [RTCMTLVideoView createNV12Renderer];
       if (![self.rendererNV12 addRenderingDestination:self.metalView]) {
@@ -118,7 +118,7 @@
         RTCLogError(@"Failed to create NV12 renderer");
       }
     }
-    renderer = self.rendererNV12;
+    [self.rendererNV12 drawFrame:videoFrame];
   } else {
     if (!self.rendererI420) {
       self.rendererI420 = [RTCMTLVideoView createI420Renderer];
@@ -127,10 +127,8 @@
         RTCLogError(@"Failed to create I420 renderer");
       }
     }
-    renderer = self.rendererI420;
+    [self.rendererI420 drawFrame:videoFrame];
   }
-
-  [renderer drawFrame:self.videoFrame];
 }
 
 - (void)mtkView:(MTKView *)view drawableSizeWillChange:(CGSize)size {