Revert "Metal rendering should account for cropping."

This reverts commit fc4a9c933326cac2eb048eb507e63021c75e705e.

Reason for revert: Remote video is not showing in a video call.

Original change's description:
> Metal rendering should account for cropping.
> 
> Also:
> - added a rotation override to allow ignoring frame rotation
> - fixed a couple of minor issues
> - made it possible to run the MTKView without the DisplayLink
> 
> Bug: webrtc:9301
> Change-Id: Ia83c152d9b6d45d56ceb80d287b5d3eacfaebddd
> Reviewed-on: https://webrtc-review.googlesource.com/78282
> Reviewed-by: Kári Helgason <kthelgason@webrtc.org>
> Reviewed-by: Anders Carlsson <andersc@webrtc.org>
> Commit-Queue: Peter Hanspers <peterhanspers@webrtc.org>
> Cr-Commit-Position: refs/heads/master@{#23452}

TBR=andersc@webrtc.org,kthelgason@webrtc.org,peterhanspers@webrtc.org

Change-Id: Iddf7793368531d2d7268c1ec138bb3a9874a4ab7
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: webrtc:9301
Reviewed-on: https://webrtc-review.googlesource.com/80020
Reviewed-by: JT Teh <jtteh@webrtc.org>
Commit-Queue: JT Teh <jtteh@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#23455}

examples/objc/AppRTCMobile/ios/ARDVideoCallView.m

@@ -43,9 +43,7 @@ static CGFloat const kStatusBarHeight = 20;
   if (self = [super initWithFrame:frame]) {
 
 #if defined(RTC_SUPPORTS_METAL)
-    RTCMTLVideoView *metalView = [[RTCMTLVideoView alloc] initWithFrame:CGRectZero];
+    _remoteVideoView = [[RTCMTLVideoView alloc] initWithFrame:CGRectZero];
-    metalView.useDisplayLink = NO;
-    _remoteVideoView = metalView;
 #else
     RTCEAGLVideoView *remoteView = [[RTCEAGLVideoView alloc] initWithFrame:CGRectZero];
     remoteView.delegate = self;

sdk/objc/Framework/Classes/Metal/RTCMTLI420Renderer.mm

@@ -90,9 +90,7 @@ static NSString *const shaderSource = MTL_STRINGIFY(
 }
 
 - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame {
-  if (![super setupTexturesForFrame:frame]) {
+  [super setupTexturesForFrame:frame];
-    return NO;
-  }
 
   id<MTLDevice> device = [self currentMetalDevice];
   if (!device) {

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

@@ -89,9 +89,7 @@ static NSString *const shaderSource = MTL_STRINGIFY(
 
 - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame {
   RTC_DCHECK([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]);
-  if ([super setupTexturesForFrame:frame] == NO) {
+  [super setupTexturesForFrame:frame];
-    return NO;
-  }
   CVPixelBufferRef pixelBuffer = ((RTCCVPixelBuffer *)frame.buffer).pixelBuffer;
 
   id<MTLTexture> lumaTexture = nil;

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

@@ -88,9 +88,7 @@ static NSString *const shaderSource = MTL_STRINGIFY(
 
 - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame {
   RTC_DCHECK([frame.buffer isKindOfClass:[RTCCVPixelBuffer class]]);
-  if ([super setupTexturesForFrame:frame] == NO) {
+  [super setupTexturesForFrame:frame];
-    return NO;
-  }
   CVPixelBufferRef pixelBuffer = ((RTCCVPixelBuffer *)frame.buffer).pixelBuffer;
 
   id<MTLTexture> gpuTexture = nil;
@@ -123,9 +121,10 @@ static NSString *const shaderSource = MTL_STRINGIFY(
 
   if (gpuTexture != nil) {
     _texture = gpuTexture;
-    _uniformsBuffer = [[self currentMetalDevice] newBufferWithBytes:&isARGB
+    _uniformsBuffer =
+        [[self currentMetalDevice] newBufferWithBytes:&isARGB
                                                length:sizeof(isARGB)
-                                                            options:MTLResourceStorageModePrivate];
+                                              options:MTLResourceCPUCacheModeDefaultCache];
     return YES;
   }
 

sdk/objc/Framework/Classes/Metal/RTCMTLRenderer.h

@@ -46,16 +46,10 @@ NS_ASSUME_NONNULL_BEGIN
 @end
 
 /**
- * Implementation of RTCMTLRenderer protocol.
+ * Implementation of RTCMTLRenderer protocol for rendering native nv12 video frames.
  */
 NS_AVAILABLE(10_11, 9_0)
 @interface RTCMTLRenderer : NSObject<RTCMTLRenderer>
-
-/** @abstract   A wrapped RTCVideoRotation, or nil.
-    @discussion When not nil, the frame rotation is ignored when rendering.
- */
-@property(atomic, nullable) NSValue *rotationOverride;
-
 @end
 
 NS_ASSUME_NONNULL_END

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

@@ -15,7 +15,6 @@
 
 #import "WebRTC/RTCLogging.h"
 #import "WebRTC/RTCVideoFrame.h"
-#import "WebRTC/RTCVideoFrameBuffer.h"
 
 #include "api/video/video_rotation.h"
 #include "rtc_base/checks.h"
@@ -29,57 +28,31 @@ static NSString *const commandBufferLabel = @"RTCCommandBuffer";
 static NSString *const renderEncoderLabel = @"RTCEncoder";
 static NSString *const renderEncoderDebugGroup = @"RTCDrawFrame";
 
-// Computes the texture coordinates given rotation and cropping.
+static const float cubeVertexData[64] = {
-static inline void getCubeVertexData(int cropX,
+    -1.0, -1.0, 0.0, 1.0, 1.0, -1.0, 1.0, 1.0, -1.0, 1.0, 0.0, 0.0, 1.0, 1.0, 1.0, 0.0,
-                                     int cropY,
-                                     int cropWidth,
-                                     int cropHeight,
-                                     size_t frameWidth,
-                                     size_t frameHeight,
-                                     RTCVideoRotation rotation,
-                                     float *buffer) {
-  // The computed values are the adjusted texture coordinates, in [0..1].
-  // For the left and top, 0.0 means no cropping and e.g. 0.2 means we're skipping 20% of the
-  // left/top edge.
-  // For the right and bottom, 1.0 means no cropping and e.g. 0.8 means we're skipping 20% of the
-  // right/bottom edge (i.e. keeping 80%).
-  float cropLeft = cropX / (float)frameWidth;
-  float cropRight = (cropX + cropWidth) / (float)frameWidth;
-  float cropTop = cropY / (float)frameHeight;
-  float cropBottom = (cropY + cropHeight) / (float)frameHeight;
 
-  // These arrays map the view coordinates to texture coordinates, taking cropping and rotation
+    // rotation = 90, offset = 16.
-  // into account. The first two columns are view coordinates, the last two are texture coordinates.
+    -1.0, -1.0, 1.0, 1.0, 1.0, -1.0, 1.0, 0.0, -1.0, 1.0, 0.0, 1.0, 1.0, 1.0, 0.0, 0.0,
+
+    // rotation = 180, offset = 32.
+    -1.0, -1.0, 1.0, 0.0, 1.0, -1.0, 0.0, 0.0, -1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 0.0, 1.0,
+
+    // rotation = 270, offset = 48.
+    -1.0, -1.0, 0.0, 0.0, 1.0, -1.0, 0.0, 1.0, -1.0, 1.0, 1.0, 0.0, 1.0, 1.0, 1.0, 1.0,
+};
+
+static inline int offsetForRotation(RTCVideoRotation rotation) {
   switch (rotation) {
-    case RTCVideoRotation_0: {
+    case RTCVideoRotation_0:
-      float values[16] = {-1.0, -1.0, cropLeft, cropBottom,
+      return 0;
-                           1.0, -1.0, cropRight, cropBottom,
+    case RTCVideoRotation_90:
-                          -1.0,  1.0, cropLeft, cropTop,
+      return 16;
-                           1.0,  1.0, cropRight, cropTop};
+    case RTCVideoRotation_180:
-      memcpy(buffer, &values, sizeof(values));
+      return 32;
-    } break;
+    case RTCVideoRotation_270:
-    case RTCVideoRotation_90: {
+      return 48;
-      float values[16] = {-1.0, -1.0, cropRight, cropBottom,
-                           1.0, -1.0, cropRight, cropTop,
-                          -1.0,  1.0, cropLeft, cropBottom,
-                           1.0,  1.0, cropLeft, cropTop};
-      memcpy(buffer, &values, sizeof(values));
-    } break;
-    case RTCVideoRotation_180: {
-      float values[16] = {-1.0, -1.0, cropRight, cropTop,
-                           1.0, -1.0, cropLeft, cropTop,
-                          -1.0,  1.0, cropRight, cropBottom,
-                           1.0,  1.0, cropLeft, cropBottom};
-      memcpy(buffer, &values, sizeof(values));
-    } break;
-    case RTCVideoRotation_270: {
-      float values[16] = {-1.0, -1.0, cropLeft, cropTop,
-                           1.0, -1.0, cropLeft, cropBottom,
-                          -1.0, 1.0, cropRight, cropTop,
-                           1.0, 1.0, cropRight, cropBottom};
-      memcpy(buffer, &values, sizeof(values));
-    } break;
   }
+  return 0;
 }
 
 // The max number of command buffers in flight (submitted to GPU).
@@ -102,20 +75,14 @@ static const NSInteger kMaxInflightBuffers = 1;
   // Buffers.
   id<MTLBuffer> _vertexBuffer;
 
-  // Values affecting the vertex buffer. Stored for comparison to avoid unnecessary recreation.
+  // RTC Frame parameters.
-  size_t _oldFrameWidth;
+  int _offset;
-  size_t _oldFrameHeight;
-  int _oldCropWidth;
-  int _oldCropHeight;
-  int _oldCropX;
-  int _oldCropY;
-  RTCVideoRotation _oldRotation;
 }
 
-@synthesize rotationOverride = _rotationOverride;
-
 - (instancetype)init {
   if (self = [super init]) {
+    // _offset of 0 is equal to rotation of 0.
+    _offset = 0;
     _inflight_semaphore = dispatch_semaphore_create(kMaxInflightBuffers);
   }
 
@@ -131,22 +98,13 @@ static const NSInteger kMaxInflightBuffers = 1;
 - (BOOL)setupWithView:(__kindof MTKView *)view {
   BOOL success = NO;
   if ([self setupMetal]) {
-    _view = view;
+    [self setupView:view];
-    view.device = _device;
-    view.preferredFramesPerSecond = 30;
-    view.autoResizeDrawable = NO;
-
-    float vertexBufferArray[16] = {0};
-    _vertexBuffer = [_device newBufferWithBytes:vertexBufferArray
-                                         length:sizeof(vertexBufferArray)
-                                        options:MTLResourceCPUCacheModeWriteCombined];
-
     [self loadAssets];
+    [self setupBuffers];
     success = YES;
   }
   return success;
 }
-
 #pragma mark - Inheritance
 
 - (id<MTLDevice>)currentMetalDevice {
@@ -163,47 +121,7 @@ static const NSInteger kMaxInflightBuffers = 1;
 }
 
 - (BOOL)setupTexturesForFrame:(nonnull RTCVideoFrame *)frame {
-  // Apply rotation override if set.
+  _offset = offsetForRotation(frame.rotation);
-  RTCVideoRotation rotation;
-  NSValue *rotationOverride = self.rotationOverride;
-  if (rotationOverride) {
-#if defined(__IPHONE_11_0) && (__IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_11_0)
-    if (@available(iOS 11, *)) {
-      [rotationOverride getValue:&rotation size:sizeof(rotation)];
-    } else
-#endif
-    {
-      [rotationOverride getValue:&rotation];
-    }
-  } else {
-    rotation = frame.rotation;
-  }
-
-  RTCCVPixelBuffer *pixelBuffer = (RTCCVPixelBuffer *)frame.buffer;
-  size_t frameWidth = CVPixelBufferGetWidth(pixelBuffer.pixelBuffer);
-  size_t frameHeight = CVPixelBufferGetHeight(pixelBuffer.pixelBuffer);
-
-  // Recompute the texture cropping and recreate vertexBuffer if necessary.
-  if (pixelBuffer.cropX != _oldCropX || pixelBuffer.cropY != _oldCropY ||
-      pixelBuffer.cropWidth != _oldCropWidth || pixelBuffer.cropHeight != _oldCropHeight ||
-      rotation != _oldRotation || frameWidth != _oldFrameWidth || frameHeight != _oldFrameHeight) {
-    getCubeVertexData(pixelBuffer.cropX,
-                      pixelBuffer.cropY,
-                      pixelBuffer.cropWidth,
-                      pixelBuffer.cropHeight,
-                      frameWidth,
-                      frameHeight,
-                      rotation,
-                      (float *)_vertexBuffer.contents);
-    _oldCropX = pixelBuffer.cropX;
-    _oldCropY = pixelBuffer.cropY;
-    _oldCropWidth = pixelBuffer.cropWidth;
-    _oldCropHeight = pixelBuffer.cropHeight;
-    _oldRotation = rotation;
-    _oldFrameWidth = frameWidth;
-    _oldFrameHeight = frameHeight;
-  }
-
   return YES;
 }
 
@@ -240,6 +158,16 @@ static const NSInteger kMaxInflightBuffers = 1;
   return YES;
 }
 
+- (void)setupView:(__kindof MTKView *)view {
+  view.device = _device;
+
+  view.preferredFramesPerSecond = 30;
+  view.autoResizeDrawable = NO;
+
+  // We need to keep reference to the view as it's needed down the rendering pipeline.
+  _view = view;
+}
+
 - (void)loadAssets {
   id<MTLFunction> vertexFunction = [_defaultLibrary newFunctionWithName:vertexFunctionName];
   id<MTLFunction> fragmentFunction = [_defaultLibrary newFunctionWithName:fragmentFunctionName];
@@ -258,6 +186,12 @@ static const NSInteger kMaxInflightBuffers = 1;
   }
 }
 
+- (void)setupBuffers {
+  _vertexBuffer = [_device newBufferWithBytes:cubeVertexData
+                                       length:sizeof(cubeVertexData)
+                                      options:MTLResourceOptionCPUCacheModeDefault];
+}
+
 - (void)render {
   // Wait until the inflight (curently sent to GPU) command buffer
   // has completed the GPU work.
@@ -281,8 +215,7 @@ static const NSInteger kMaxInflightBuffers = 1;
     // Set context state.
     [renderEncoder pushDebugGroup:renderEncoderDebugGroup];
     [renderEncoder setRenderPipelineState:_pipelineState];
-
+    [renderEncoder setVertexBuffer:_vertexBuffer offset:_offset * sizeof(float) atIndex:0];
-    [renderEncoder setVertexBuffer:_vertexBuffer offset:0 atIndex:0];
     [self uploadTexturesToRenderEncoder:renderEncoder];
 
     [renderEncoder drawPrimitives:MTLPrimitiveTypeTriangleStrip

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

@@ -29,16 +29,17 @@
 #define RTCMTLRGBRendererClass NSClassFromString(@"RTCMTLRGBRenderer")
 
 @interface RTCMTLVideoView () <MTKViewDelegate>
-@property(nonatomic) RTCMTLI420Renderer *rendererI420;
+@property(nonatomic, strong) RTCMTLI420Renderer *rendererI420;
-@property(nonatomic) RTCMTLNV12Renderer *rendererNV12;
+@property(nonatomic, strong) RTCMTLNV12Renderer *rendererNV12;
-@property(nonatomic) RTCMTLRGBRenderer *rendererRGB;
+@property(nonatomic, strong) RTCMTLRGBRenderer *rendererRGB;
-@property(nonatomic) MTKView *metalView;
+@property(nonatomic, strong) MTKView *metalView;
-@property(atomic) RTCVideoFrame *videoFrame;
+@property(atomic, strong) RTCVideoFrame *videoFrame;
-@property(nonatomic) CGSize videoFrameSize;
-@property(nonatomic) int64_t lastFrameTimeNs;
 @end
 
-@implementation RTCMTLVideoView
+@implementation RTCMTLVideoView {
+  int64_t _lastFrameTimeNs;
+  CGSize _videoFrameSize;
+}
 
 @synthesize delegate = _delegate;
 @synthesize rendererI420 = _rendererI420;
@@ -46,11 +47,6 @@
 @synthesize rendererRGB = _rendererRGB;
 @synthesize metalView = _metalView;
 @synthesize videoFrame = _videoFrame;
-@synthesize useDisplayLink = _useDisplayLink;
-@synthesize videoFrameSize = _videoFrameSize;
-@synthesize lastFrameTimeNs = _lastFrameTimeNs;
-@synthesize enabled = _enabled;
-@synthesize rotationOverride = _rotationOverride;
 
 - (instancetype)initWithFrame:(CGRect)frameRect {
   self = [super initWithFrame:frameRect];
@@ -68,36 +64,8 @@
   return self;
 }
 
-- (void)setUseDisplayLink:(BOOL)useDisplayLink {
-  _useDisplayLink = useDisplayLink;
-  [self updateRunningState];
-}
-
-- (void)setEnabled:(BOOL)enabled {
-  _enabled = enabled;
-  [self updateRunningState];
-}
-
-- (UIViewContentMode)videoContentMode {
-  return self.metalView.contentMode;
-}
-
-- (void)setVideoContentMode:(UIViewContentMode)mode {
-  self.metalView.contentMode = mode;
-}
-
 #pragma mark - Private
 
-- (void)updateRunningState {
-  if (self.useDisplayLink) {
-    self.metalView.paused = !self.enabled;
-    self.metalView.enableSetNeedsDisplay = YES;
-  } else {
-    self.metalView.paused = YES;
-    self.metalView.enableSetNeedsDisplay = NO;
-  }
-}
-
 + (BOOL)isMetalAvailable {
 #if defined(RTC_SUPPORTS_METAL)
   return MTLCreateSystemDefaultDevice() != nil;
@@ -106,6 +74,11 @@
 #endif
 }
 
++ (MTKView *)createMetalView:(CGRect)frame {
+  MTKView *view = [[MTKViewClass alloc] initWithFrame:frame];
+  return view;
+}
+
 + (RTCMTLNV12Renderer *)createNV12Renderer {
   return [[RTCMTLNV12RendererClass alloc] init];
 }
@@ -121,28 +94,33 @@
 - (void)configure {
   NSAssert([RTCMTLVideoView isMetalAvailable], @"Metal not availiable on this device");
 
-  _enabled = YES;
+  _metalView = [RTCMTLVideoView createMetalView:self.bounds];
-  _useDisplayLink = YES;
+  [self configureMetalView];
-  [self updateRunningState];
-
-  self.metalView = [[MTKViewClass alloc] initWithFrame:self.bounds];
-  self.metalView.delegate = self;
-  self.metalView.paused = YES;
-  self.metalView.enableSetNeedsDisplay = NO;
-  self.metalView.contentMode = UIViewContentModeScaleAspectFill;
-  [self addSubview:self.metalView];
-  self.videoFrameSize = CGSizeZero;
 }
 
+- (void)configureMetalView {
+  if (_metalView) {
+    _metalView.delegate = self;
+    [self addSubview:_metalView];
+    _metalView.contentMode = UIViewContentModeScaleAspectFit;
+    _videoFrameSize = CGSizeZero;
+  }
+}
+
+- (void)setVideoContentMode:(UIViewContentMode)mode {
+  _metalView.contentMode = mode;
+}
+
+#pragma mark - Private
+
 - (void)layoutSubviews {
   [super layoutSubviews];
-
   CGRect bounds = self.bounds;
-  self.metalView.frame = bounds;
+  _metalView.frame = bounds;
-  if (!CGSizeEqualToSize(self.videoFrameSize, CGSizeZero)) {
+  if (!CGSizeEqualToSize(_videoFrameSize, CGSizeZero)) {
-    self.metalView.drawableSize = [self drawableSize];
+    _metalView.drawableSize = _videoFrameSize;
   } else {
-    self.metalView.drawableSize = bounds.size;
+    _metalView.drawableSize = bounds.size;
   }
 }
 
@@ -152,11 +130,10 @@
   NSAssert(view == self.metalView, @"Receiving draw callbacks from foreign instance.");
   RTCVideoFrame *videoFrame = self.videoFrame;
   // Skip rendering if we've already rendered this frame.
-  if (!videoFrame || videoFrame.timeStampNs == self.lastFrameTimeNs) {
+  if (!videoFrame || videoFrame.timeStampNs == _lastFrameTimeNs) {
     return;
   }
 
-  RTCMTLRenderer *renderer;
   if ([videoFrame.buffer isKindOfClass:[RTCCVPixelBuffer class]]) {
     RTCCVPixelBuffer *buffer = (RTCCVPixelBuffer*)videoFrame.buffer;
     const OSType pixelFormat = CVPixelBufferGetPixelFormatType(buffer.pixelBuffer);
@@ -169,7 +146,7 @@
           return;
         }
       }
-      renderer = self.rendererRGB;
+      [self.rendererRGB drawFrame:videoFrame];
     } else {
       if (!self.rendererNV12) {
         self.rendererNV12 = [RTCMTLVideoView createNV12Renderer];
@@ -179,7 +156,7 @@
           return;
         }
       }
-      renderer = self.rendererNV12;
+      [self.rendererNV12 drawFrame:videoFrame];
     }
   } else {
     if (!self.rendererI420) {
@@ -190,82 +167,30 @@
         return;
       }
     }
-    renderer = self.rendererI420;
+    [self.rendererI420 drawFrame:videoFrame];
   }
-
+  _lastFrameTimeNs = videoFrame.timeStampNs;
-  renderer.rotationOverride = self.rotationOverride;
-
-  [renderer drawFrame:videoFrame];
-  self.lastFrameTimeNs = videoFrame.timeStampNs;
 }
 
 - (void)mtkView:(MTKView *)view drawableSizeWillChange:(CGSize)size {
 }
 
-- (RTCVideoRotation)frameRotation {
-  if (self.rotationOverride) {
-    RTCVideoRotation rotation;
-#if defined(__IPHONE_11_0) && (__IPHONE_OS_VERSION_MAX_ALLOWED >= __IPHONE_11_0)
-    if (@available(iOS 11, *)) {
-      [self.rotationOverride getValue:&rotation size:sizeof(rotation)];
-    } else
-#endif
-    {
-      [self.rotationOverride getValue:&rotation];
-    }
-    return rotation;
-  }
-
-  return self.videoFrame.rotation;
-}
-
-- (CGSize)drawableSize {
-  // Flip width/height if the rotations are not the same.
-  CGSize videoFrameSize = self.videoFrameSize;
-
-  BOOL useLandscape = ([self frameRotation] == RTCVideoRotation_0) ||
-      ([self frameRotation] == RTCVideoRotation_180);
-  BOOL sizeIsLandscape = (self.videoFrame.rotation == RTCVideoRotation_0) ||
-      (self.videoFrame.rotation == RTCVideoRotation_180);
-
-  if (useLandscape == sizeIsLandscape) {
-    return videoFrameSize;
-  } else {
-    return CGSizeMake(videoFrameSize.height, videoFrameSize.width);
-  }
-}
-
 #pragma mark - RTCVideoRenderer
 
 - (void)setSize:(CGSize)size {
-  __weak RTCMTLVideoView *weakSelf = self;
+  self.metalView.drawableSize = size;
   dispatch_async(dispatch_get_main_queue(), ^{
-    RTCMTLVideoView *strongSelf = weakSelf;
+    _videoFrameSize = size;
-
+    [self.delegate videoView:self didChangeVideoSize:size];
-    strongSelf.videoFrameSize = size;
-    CGSize drawableSize = [strongSelf drawableSize];
-
-    strongSelf.metalView.drawableSize = drawableSize;
-    [strongSelf setNeedsLayout];
-    [strongSelf.delegate videoView:self didChangeVideoSize:size];
   });
 }
 
 - (void)renderFrame:(nullable RTCVideoFrame *)frame {
-  if (!self.isEnabled) {
-    return;
-  }
-
   if (frame == nil) {
     RTCLogInfo(@"Incoming frame is nil. Exiting render callback.");
     return;
   }
-
   self.videoFrame = frame;
-
-  if (!self.useDisplayLink) {
-    [self.metalView draw];
-  }
 }
 
 @end

sdk/objc/Framework/Headers/WebRTC/RTCMTLVideoView.h

@@ -10,7 +10,6 @@
 
 #import <Foundation/Foundation.h>
 
-#import "WebRTC/RTCVideoFrame.h"
 #import "WebRTC/RTCVideoRenderer.h"
 
 // Check if metal is supported in WebRTC.
@@ -36,21 +35,7 @@ RTC_EXPORT
 
 @property(nonatomic, weak) id<RTCVideoViewDelegate> delegate;
 
-@property(nonatomic) UIViewContentMode videoContentMode;
+- (void)setVideoContentMode:(UIViewContentMode)mode;
-
-/** @abstract Enables/disables rendering.
- */
-@property(nonatomic, getter=isEnabled) BOOL enabled;
-
-/** @abstract   If YES, the backing MTKView will use a display link to issue
-   draw calls.
-    @discussion Default is YES.
- */
-@property(nonatomic) BOOL useDisplayLink;
-
-/** @abstract Wrapped RTCVideoRotation, or nil.
- */
-@property(nullable) NSValue* rotationOverride;
 
 @end