rhubarb-lip-sync/rhubarb/lib/webrtc-8d2248ff/talk/app/webrtc/objc/RTCEAGLVideoView.m

278 lines
8.7 KiB
Objective-C

/*
* libjingle
* Copyright 2014 Google Inc.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
* 3. The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
* EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
* PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
* OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
* WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
* OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#if !defined(__has_feature) || !__has_feature(objc_arc)
#error "This file requires ARC support."
#endif
#import "RTCEAGLVideoView.h"
#import <GLKit/GLKit.h>
#import "RTCI420Frame.h"
#import "RTCOpenGLVideoRenderer.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>
// |i420Frame| 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) RTCI420Frame* i420Frame;
@property(nonatomic, readonly) GLKView* glkView;
@property(nonatomic, readonly) RTCOpenGLVideoRenderer* glRenderer;
@end
@implementation RTCEAGLVideoView {
RTCDisplayLinkTimer* _timer;
GLKView* _glkView;
RTCOpenGLVideoRenderer* _glRenderer;
// This flag should only be set and read on the main thread (e.g. by
// setNeedsDisplay)
BOOL _isDirty;
}
- (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.i420Frame];
}
#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:(RTCI420Frame*)frame {
self.i420Frame = 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.i420Frame) {
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.i420Frame = nil;
[_glRenderer setupGL];
_timer.isPaused = NO;
}
- (void)teardownGL {
self.i420Frame = nil;
_timer.isPaused = YES;
[_glkView deleteDrawable];
[_glRenderer teardownGL];
}
- (void)didBecomeActive {
[self setupGL];
}
- (void)willResignActive {
[self teardownGL];
}
@end