Moving src/webrtc into src/.

In order to eliminate the WebRTC Subtree mirror in Chromium, 
WebRTC is moving the content of the src/webrtc directory up
to the src/ directory.

NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
TBR=tommi@webrtc.org

Bug: chromium:611808
Change-Id: Iac59c5b51b950f174119565bac87955a7994bc38
Reviewed-on: https://webrtc-review.googlesource.com/1560
Commit-Queue: Mirko Bonadei <mbonadei@webrtc.org>
Reviewed-by: Henrik Kjellander <kjellander@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#19845}

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

@@ -0,0 +1,152 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+#import "WebRTC/RTCMTLVideoView.h"
+
+#import <Metal/Metal.h>
+#import <MetalKit/MetalKit.h>
+
+#import "WebRTC/RTCLogging.h"
+#import "WebRTC/RTCVideoFrame.h"
+#import "WebRTC/RTCVideoFrameBuffer.h"
+
+#import "RTCMTLI420Renderer.h"
+#import "RTCMTLNV12Renderer.h"
+
+// To avoid unreconized symbol linker errors, we're taking advantage of the objc runtime.
+// Linking errors occur when compiling for architectures that don't support Metal.
+#define MTKViewClass NSClassFromString(@"MTKView")
+#define RTCMTLNV12RendererClass NSClassFromString(@"RTCMTLNV12Renderer")
+#define RTCMTLI420RendererClass NSClassFromString(@"RTCMTLI420Renderer")
+
+@interface RTCMTLVideoView () <MTKViewDelegate>
+@property(nonatomic, strong) RTCMTLI420Renderer *rendererI420;
+@property(nonatomic, strong) RTCMTLNV12Renderer *rendererNV12;
+@property(nonatomic, strong) MTKView *metalView;
+@property(atomic, strong) RTCVideoFrame *videoFrame;
+@end
+
+@implementation RTCMTLVideoView
+
+@synthesize rendererI420 = _rendererI420;
+@synthesize rendererNV12 = _rendererNV12;
+@synthesize metalView = _metalView;
+@synthesize videoFrame = _videoFrame;
+
+- (instancetype)initWithFrame:(CGRect)frameRect {
+  self = [super initWithFrame:frameRect];
+  if (self) {
+    [self configure];
+  }
+  return self;
+}
+
+- (instancetype)initWithCoder:(NSCoder *)aCoder {
+  self = [super initWithCoder:aCoder];
+  if (self) {
+    [self configure];
+  }
+  return self;
+}
+
+#pragma mark - Private
+
++ (BOOL)isMetalAvailable {
+#if defined(RTC_SUPPORTS_METAL)
+  return YES;
+#else
+  return NO;
+#endif
+}
+
++ (MTKView *)createMetalView:(CGRect)frame {
+  MTKView *view = [[MTKViewClass alloc] initWithFrame:frame];
+  return view;
+}
+
++ (RTCMTLNV12Renderer *)createNV12Renderer {
+  return [[RTCMTLNV12RendererClass alloc] init];
+}
+
++ (RTCMTLI420Renderer *)createI420Renderer {
+  return [[RTCMTLI420RendererClass alloc] init];
+}
+
+- (void)configure {
+  NSAssert([RTCMTLVideoView isMetalAvailable], @"Metal not availiable on this device");
+
+  _metalView = [RTCMTLVideoView createMetalView:self.bounds];
+  [self configureMetalView];
+}
+
+- (void)configureMetalView {
+  if (_metalView) {
+    _metalView.delegate = self;
+    [self addSubview:_metalView];
+    _metalView.contentMode = UIViewContentModeScaleAspectFit;
+    _metalView.translatesAutoresizingMaskIntoConstraints = NO;
+    UILayoutGuide *margins = self.layoutMarginsGuide;
+    [_metalView.topAnchor constraintEqualToAnchor:margins.topAnchor].active = YES;
+    [_metalView.bottomAnchor constraintEqualToAnchor:margins.bottomAnchor].active = YES;
+    [_metalView.leftAnchor constraintEqualToAnchor:margins.leftAnchor].active = YES;
+    [_metalView.rightAnchor constraintEqualToAnchor:margins.rightAnchor].active = YES;
+  }
+}
+
+#pragma mark - MTKViewDelegate methods
+
+- (void)drawInMTKView:(nonnull MTKView *)view {
+  NSAssert(view == self.metalView, @"Receiving draw callbacks from foreign instance.");
+  if (!self.videoFrame) {
+    return;
+  }
+
+  id<RTCMTLRenderer> renderer = nil;
+  if ([self.videoFrame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
+    if (!self.rendererNV12) {
+      self.rendererNV12 = [RTCMTLVideoView createNV12Renderer];
+      if (![self.rendererNV12 addRenderingDestination:self.metalView]) {
+        self.rendererNV12 = nil;
+        RTCLogError(@"Failed to create NV12 renderer");
+      }
+    }
+    renderer = self.rendererNV12;
+  } else {
+    if (!self.rendererI420) {
+      self.rendererI420 = [RTCMTLVideoView createI420Renderer];
+      if (![self.rendererI420 addRenderingDestination:self.metalView]) {
+        self.rendererI420 = nil;
+        RTCLogError(@"Failed to create I420 renderer");
+      }
+    }
+    renderer = self.rendererI420;
+  }
+
+  [renderer drawFrame:self.videoFrame];
+}
+
+- (void)mtkView:(MTKView *)view drawableSizeWillChange:(CGSize)size {
+}
+
+#pragma mark - RTCVideoRenderer
+
+- (void)setSize:(CGSize)size {
+  self.metalView.drawableSize = size;
+}
+
+- (void)renderFrame:(nullable RTCVideoFrame *)frame {
+  if (frame == nil) {
+    RTCLogInfo(@"Incoming frame is nil. Exiting render callback.");
+    return;
+  }
+  self.videoFrame = frame;
+}
+
+@end