rhubarb-lip-sync/lib/webrtc-8d2248ff/webrtc/sdk/objc/Framework/Classes/RTCEAGLVideoView.m

264 lines
7.9 KiB
Objective-C

/*
* Copyright 2015 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/RTCEAGLVideoView.h"
#import <GLKit/GLKit.h>
#import "RTCOpenGLVideoRenderer.h"
#import "WebRTC//RTCVideoFrame.h"
// RTCDisplayLinkTimer wraps a CADisplayLink and is set to fire every two screen
// refreshes, which should be 30fps. We wrap the display link in order to avoid
// a retain cycle since CADisplayLink takes a strong reference onto its target.
// The timer is paused by default.
@interface RTCDisplayLinkTimer : NSObject
@property(nonatomic) BOOL isPaused;
- (instancetype)initWithTimerHandler:(void (^)(void))timerHandler;
- (void)invalidate;
@end
@implementation RTCDisplayLinkTimer {
CADisplayLink *_displayLink;
void (^_timerHandler)(void);
}
- (instancetype)initWithTimerHandler:(void (^)(void))timerHandler {
NSParameterAssert(timerHandler);
if (self = [super init]) {
_timerHandler = timerHandler;
_displayLink =
[CADisplayLink displayLinkWithTarget:self
selector:@selector(displayLinkDidFire:)];
_displayLink.paused = YES;
// Set to half of screen refresh, which should be 30fps.
[_displayLink setFrameInterval:2];
[_displayLink addToRunLoop:[NSRunLoop currentRunLoop]
forMode:NSRunLoopCommonModes];
}
return self;
}
- (void)dealloc {
[self invalidate];
}
- (BOOL)isPaused {
return _displayLink.paused;
}
- (void)setIsPaused:(BOOL)isPaused {
_displayLink.paused = isPaused;
}
- (void)invalidate {
[_displayLink invalidate];
}
- (void)displayLinkDidFire:(CADisplayLink *)displayLink {
_timerHandler();
}
@end
// RTCEAGLVideoView wraps a GLKView which is setup with
// enableSetNeedsDisplay = NO for the purpose of gaining control of
// exactly when to call -[GLKView display]. This need for extra
// control is required to avoid triggering method calls on GLKView
// that results in attempting to bind the underlying render buffer
// when the drawable size would be empty which would result in the
// error GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT. -[GLKView display] is
// the method that will trigger the binding of the render
// buffer. Because the standard behaviour of -[UIView setNeedsDisplay]
// is disabled for the reasons above, the RTCEAGLVideoView maintains
// its own |isDirty| flag.
@interface RTCEAGLVideoView () <GLKViewDelegate>
// |videoFrame| is set when we receive a frame from a worker thread and is read
// from the display link callback so atomicity is required.
@property(atomic, strong) RTCVideoFrame *videoFrame;
@property(nonatomic, readonly) GLKView *glkView;
@property(nonatomic, readonly) RTCOpenGLVideoRenderer *glRenderer;
@end
@implementation RTCEAGLVideoView {
RTCDisplayLinkTimer *_timer;
// This flag should only be set and read on the main thread (e.g. by
// setNeedsDisplay)
BOOL _isDirty;
}
@synthesize delegate = _delegate;
@synthesize videoFrame = _videoFrame;
@synthesize glkView = _glkView;
@synthesize glRenderer = _glRenderer;
- (instancetype)initWithFrame:(CGRect)frame {
if (self = [super initWithFrame:frame]) {
[self configure];
}
return self;
}
- (instancetype)initWithCoder:(NSCoder *)aDecoder {
if (self = [super initWithCoder:aDecoder]) {
[self configure];
}
return self;
}
- (void)configure {
EAGLContext *glContext =
[[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES3];
if (!glContext) {
glContext = [[EAGLContext alloc] initWithAPI:kEAGLRenderingAPIOpenGLES2];
}
_glRenderer = [[RTCOpenGLVideoRenderer alloc] initWithContext:glContext];
// GLKView manages a framebuffer for us.
_glkView = [[GLKView alloc] initWithFrame:CGRectZero
context:glContext];
_glkView.drawableColorFormat = GLKViewDrawableColorFormatRGBA8888;
_glkView.drawableDepthFormat = GLKViewDrawableDepthFormatNone;
_glkView.drawableStencilFormat = GLKViewDrawableStencilFormatNone;
_glkView.drawableMultisample = GLKViewDrawableMultisampleNone;
_glkView.delegate = self;
_glkView.layer.masksToBounds = YES;
_glkView.enableSetNeedsDisplay = NO;
[self addSubview:_glkView];
// Listen to application state in order to clean up OpenGL before app goes
// away.
NSNotificationCenter *notificationCenter =
[NSNotificationCenter defaultCenter];
[notificationCenter addObserver:self
selector:@selector(willResignActive)
name:UIApplicationWillResignActiveNotification
object:nil];
[notificationCenter addObserver:self
selector:@selector(didBecomeActive)
name:UIApplicationDidBecomeActiveNotification
object:nil];
// Frames are received on a separate thread, so we poll for current frame
// using a refresh rate proportional to screen refresh frequency. This
// occurs on the main thread.
__weak RTCEAGLVideoView *weakSelf = self;
_timer = [[RTCDisplayLinkTimer alloc] initWithTimerHandler:^{
RTCEAGLVideoView *strongSelf = weakSelf;
[strongSelf displayLinkTimerDidFire];
}];
[self setupGL];
}
- (void)dealloc {
[[NSNotificationCenter defaultCenter] removeObserver:self];
UIApplicationState appState =
[UIApplication sharedApplication].applicationState;
if (appState == UIApplicationStateActive) {
[self teardownGL];
}
[_timer invalidate];
}
#pragma mark - UIView
- (void)setNeedsDisplay {
[super setNeedsDisplay];
_isDirty = YES;
}
- (void)setNeedsDisplayInRect:(CGRect)rect {
[super setNeedsDisplayInRect:rect];
_isDirty = YES;
}
- (void)layoutSubviews {
[super layoutSubviews];
_glkView.frame = self.bounds;
}
#pragma mark - GLKViewDelegate
// This method is called when the GLKView's content is dirty and needs to be
// redrawn. This occurs on main thread.
- (void)glkView:(GLKView *)view drawInRect:(CGRect)rect {
// The renderer will draw the frame to the framebuffer corresponding to the
// one used by |view|.
[_glRenderer drawFrame:self.videoFrame];
}
#pragma mark - RTCVideoRenderer
// These methods may be called on non-main thread.
- (void)setSize:(CGSize)size {
__weak RTCEAGLVideoView *weakSelf = self;
dispatch_async(dispatch_get_main_queue(), ^{
RTCEAGLVideoView *strongSelf = weakSelf;
[strongSelf.delegate videoView:strongSelf didChangeVideoSize:size];
});
}
- (void)renderFrame:(RTCVideoFrame *)frame {
// Generate the i420 frame on video send thread instead of main thread.
// TODO(tkchin): Remove this once RTCEAGLVideoView supports uploading
// CVPixelBuffer textures.
[frame convertBufferIfNeeded];
self.videoFrame = frame;
}
#pragma mark - Private
- (void)displayLinkTimerDidFire {
// Don't render unless video frame have changed or the view content
// has explicitly been marked dirty.
if (!_isDirty && _glRenderer.lastDrawnFrame == self.videoFrame) {
return;
}
// Always reset isDirty at this point, even if -[GLKView display]
// won't be called in the case the drawable size is empty.
_isDirty = NO;
// Only call -[GLKView display] if the drawable size is
// non-empty. Calling display will make the GLKView setup its
// render buffer if necessary, but that will fail with error
// GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT if size is empty.
if (self.bounds.size.width > 0 && self.bounds.size.height > 0) {
[_glkView display];
}
}
- (void)setupGL {
self.videoFrame = nil;
[_glRenderer setupGL];
_timer.isPaused = NO;
}
- (void)teardownGL {
self.videoFrame = nil;
_timer.isPaused = YES;
[_glkView deleteDrawable];
[_glRenderer teardownGL];
}
- (void)didBecomeActive {
[self setupGL];
}
- (void)willResignActive {
[self teardownGL];
}
@end