Misc: fix bugs that were preventing starting a new stream after disconnecting. Known issue: this leaks a bit of memory. This also removes all OSX-specific code from the Apple example I used, as I have no intention of using this on Mac.

VoidLink/Metal/MetalVideoRenderer.m

@@ -158,6 +158,11 @@ CFStringRef __currentColorSpace;
 }
 
 - (void)dealloc {
+    Log(LOG_I, @"MetalVideoRenderer dealloc");
+
+    if (_commandQueue) {
+        _commandQueue = nil;
+    }
     if (_CscParamsBuffer) {
         _CscParamsBuffer = nil;
     }
@@ -172,6 +177,9 @@ CFStringRef __currentColorSpace;
     if (_renderPassDescriptor) {
         _renderPassDescriptor = nil;
     }
+    if (_textureCache) {
+        _textureCache = nil;
+    }
     if (__currentColorSpace) {
         CFRelease(__currentColorSpace);
     }
@@ -179,12 +187,7 @@ CFStringRef __currentColorSpace;
 
 #if !TARGET_OS_TV
 - (void)reportMaxEDRHeadroom {
-    CGFloat maxHeadroom = 1.0f;
+    CGFloat maxHeadroom = [[UIScreen mainScreen] potentialEDRHeadroom];
-#if TARGET_OS_OSX
-    maxHeadroom = [[NSScreen mainScreen] maximumPotentialExtendedDynamicRangeColorComponentValue];
-#else
-    maxHeadroom = [[UIScreen mainScreen] potentialEDRHeadroom];
-#endif
     if (maxHeadroom > 1.0) {
         LogOnce(LOG_I, @"Display supports EDR with a max headroom of %.1f", maxHeadroom);
     } else {
@@ -193,12 +196,7 @@ CFStringRef __currentColorSpace;
 }
 
 - (void)pollCurrentEDRHeadroom {
-    CGFloat headroom = 1.0f;
+    CGFloat headroom = [[UIScreen mainScreen] currentEDRHeadroom];
-#if TARGET_OS_OSX
-    headroom = [[NSScreen mainScreen] maximumExtendedDynamicRangeColorComponentValue];
-#else
-    headroom = [[UIScreen mainScreen] currentEDRHeadroom];
-#endif
     if (headroom != _currentEDRHeadroom) {
         Log(LOG_I, @"EDR headroom changed to %.1f", headroom);
         _currentEDRHeadroom = (float)headroom;
@@ -448,7 +446,7 @@ CFStringRef __currentColorSpace;
 - (void)renderFrame:(Frame *)frame toLayer:(CAMetalLayer *)layer {
     @autoreleasepool {
         if (self.isStopping) {
-            Log(LOG_I, @"XXX Metal renderThread is stopping. returning from renderFrame");
+            Log(LOG_I, @"[MetalVideoRenderer] isStopping");
             return;
         }
 
@@ -573,10 +571,12 @@ CFStringRef __currentColorSpace;
 
         [renderEncoder setVertexBuffer:_VideoVertexBuffer offset:0 atIndex:0];
         [renderEncoder setFragmentBuffer:_CscParamsBuffer offset:0 atIndex:0];
+#if !TARGET_OS_TV
         if (layer.pixelFormat == MTLPixelFormatRGBA16Float) {
             [self pollCurrentEDRHeadroom];
             [renderEncoder setFragmentBytes:&_currentEDRHeadroom length:sizeof(float) atIndex:1];
         }
+#endif
         [renderEncoder drawPrimitives:MTLPrimitiveTypeTriangleStrip vertexStart:0 vertexCount:4];
         [renderEncoder endEncoding];
 
@@ -617,8 +617,6 @@ CFStringRef __currentColorSpace;
 #endif
 
         [commandBuffer commit];
-
-        // Wait for the command buffer to complete and free our CVMetalTextureCache references
         [commandBuffer waitUntilCompleted];
     }
 }
@@ -633,12 +631,14 @@ CFStringRef __currentColorSpace;
 }
 
 - (void)shutdown {
-    Log(LOG_I, @"XXX MetalVideoRenderer shutodwn");
+    if (!self.isStopping) {
-    self.isStopping = YES;
+        self.isStopping = YES;
+        Log(LOG_I, @"[MetalVideoRenderer] shutdown");
 
-    // Ensure no rendering is in flight
+        // Ensure no rendering is in flight
-    for (NSUInteger i = 0; i < MaxFramesInFlight; i++) {
+        for (NSUInteger i = 0; i < MaxFramesInFlight; i++) {
-        dispatch_semaphore_signal(_inFlightSemaphore);
+            dispatch_semaphore_signal(_inFlightSemaphore);
+        }
     }
 }
 

VoidLink/Metal/MetalView.h

@@ -1,15 +1,8 @@
 #import <Metal/Metal.h>
 #import <QuartzCore/CAMetalDisplayLink.h>
 #import <QuartzCore/CAMetalLayer.h>
-#import "MetalConfig.h"
-
-#if TARGET_OS_IOS || TARGET_OS_TV
 #import <UIKit/UIKit.h>
-#define PlatformView UIView
+#import "MetalConfig.h"
-#else
-#import <AppKit/AppKit.h>
-#define PlatformView NSView
-#endif
 
 // The protocol to provide resize and redraw callbacks to a delegate.
 @protocol MetalViewDelegate <NSObject>
@@ -17,15 +10,13 @@
 - (void)drawableResize:(CGSize)size;
 - (void)renderTo:(nonnull CAMetalLayer *)layer;
 - (void)waitToRenderTo:(nonnull CAMetalLayer *)layer;
-- (void)shutdown;
 
 @end
 
 // The Metal game view base class.
-@interface MetalView : PlatformView <CALayerDelegate>
+@interface MetalView : UIView <CALayerDelegate>
 
 @property (nonatomic, nonnull, readonly) CAMetalLayer *metalLayer;
-@property (nonatomic, getter=isPaused) BOOL paused;
 @property (nonatomic, nullable) id<MetalViewDelegate> delegate;
 @property (nonatomic) float framerate;
 

VoidLink/Metal/MetalView.m

@@ -1,4 +1,4 @@
-// This is based on the following Apple example:
+// This is based on the following Apple example
 // https://developer.apple.com/documentation/metal/achieving-smooth-frame-rates-with-a-metal-display-link?language=objc
 // https://developer.apple.com/wwdc23/10123/
 
@@ -29,29 +29,23 @@
 }
 
 - (void)initCommon {
-#if TARGET_OS_OSX
-    self.wantsLayer = YES;
-
-    self.layerContentsRedrawPolicy = NSViewLayerContentsRedrawDuringViewResize;
-#endif
-
     _metalLayer = (CAMetalLayer *)self.layer;
-
     self.layer.delegate = self;
 }
 
 - (void)shutdown {
     if (_renderThread) {
+        Log(LOG_I, @"[MetalView] sending renderThread a cancel message");
         [_renderThread cancel];
-        // wait for thread to exist
+        Log(LOG_I, @"[MetalView] waiting on renderThread to finish");
         while (!_renderThread.isFinished) {
-            Log(LOG_I, @"XXX MetalView waiting on renderThread to finish");
             usleep(100);
         }
+        Log(LOG_I, @"[MetalView] renderThread has finished");
+        _renderThread = nil;
     }
 }
 
-#if TARGET_OS_IOS || TARGET_OS_TV
 + (Class)layerClass {
     return [CAMetalLayer class];
 }
@@ -59,29 +53,11 @@
 - (void)didMoveToWindow {
     [self movedToWindow];
 }
-#else
-- (CALayer *)makeBackingLayer {
-    return [CAMetalLayer layer];
-}
-
-- (void)viewDidMoveToWindow {
-    [self movedToWindow];
-}
-#endif  // END TARGET_OS_IOS || TARGET_OS_TV
 
 - (void)movedToWindow {
     if (!self.window) {
-        return;
+        Log(LOG_I, @"[MetalView] movedToWindow(nil): shutting down...");
-
+        [self shutdown];
-        // We have been removed
-        if (_renderThread) {
-            [_renderThread cancel];
-            // wait for thread to exist
-            while (!_renderThread.isFinished) {
-                Log(LOG_I, @"XXX MetalView waiting on renderThread to finish");
-                usleep(100);
-            }
-        }
         return;
     }
 
@@ -93,21 +69,18 @@
                 [self.delegate renderTo:self.metalLayer];
             }
         }
-        Log(LOG_I, @"XXX Metal renderThread shutting down");
+        Log(LOG_I, @"[MetalView] renderThread is exiting");
     }];
     _renderThread.name = @"MetalVideoRenderer";
     _renderThread.qualityOfService = NSQualityOfServiceUserInteractive;
     [_renderThread start];
+    Log(LOG_I, @"[MetalView] started renderThread %@", _renderThread);
 
     // Perform any actions that need to know the size and scale of the drawable. When UIKit calls
     // didMoveToWindow after the view initialization, this is the first opportunity to notify
     // components of the drawable's size.
 #if AUTOMATICALLY_RESIZE
-#if TARGET_OS_IOS || TARGET_OS_TV
     [self resizeDrawable:self.window.screen.nativeScale];
-#else
-    [self resizeDrawable:self.window.screen.backingScaleFactor];
-#endif
 #else
     // Notify the delegate of the default drawable size when the system can calculate it.
     CGSize defaultDrawableSize = self.bounds.size;
@@ -123,7 +96,6 @@
 
 // Override all methods that indicate the view's size has changed.
 
-#if TARGET_OS_IOS || TARGET_OS_TV
 - (void)setContentScaleFactor:(CGFloat)contentScaleFactor {
     [super setContentScaleFactor:contentScaleFactor];
     [self resizeDrawable:self.window.screen.nativeScale];
@@ -143,22 +115,6 @@
     [super setBounds:bounds];
     [self resizeDrawable:self.window.screen.nativeScale];
 }
-#else
-- (void)viewDidChangeBackingProperties {
-    [super viewDidChangeBackingProperties];
-    [self resizeDrawable:self.window.screen.backingScaleFactor];
-}
-
-- (void)setFrameSize:(NSSize)size {
-    [super setFrameSize:size];
-    [self resizeDrawable:self.window.screen.backingScaleFactor];
-}
-
-- (void)setBoundsSize:(NSSize)size {
-    [super setBoundsSize:size];
-    [self resizeDrawable:self.window.screen.backingScaleFactor];
-}
-#endif
 
 - (void)resizeDrawable:(CGFloat)scaleFactor {
     CGSize newSize = self.bounds.size;

VoidLink/Metal/MetalViewController.h

@@ -1,18 +1,11 @@
 #import <Metal/Metal.h>
+#import <UIKit/UIKit.h>
 #import "FrameQueue.h"
 #import "ImGuiRenderer.h"
 #import "MetalVideoRenderer.h"
 #import "MetalView.h"
 
-#if TARGET_OS_IOS || TARGET_OS_TV
+@interface MetalViewController : UIViewController <MetalViewDelegate>
-#import <UIKit/UIKit.h>
-#define PlatformViewController UIViewController
-#else
-#import <AppKit/AppKit.h>
-#define PlatformViewController NSViewController
-#endif
-
-@interface MetalViewController : PlatformViewController <MetalViewDelegate>
 
 @property (nonatomic) CGRect bounds;
 

VoidLink/Metal/MetalViewController.m

@@ -33,6 +33,7 @@ The implementation of the cross-platform game view controller.
 
 - (void)loadView {
     self.view = [[MetalView alloc] initWithFrame:_bounds];
+    Log(LOG_I, @"[MetalViewController] created MetalView %@", (MetalView *)self.view);
 }
 
 - (void)viewDidLoad {
@@ -51,7 +52,7 @@ The implementation of the cross-platform game view controller.
     id<MTLDevice> device = MTLCreateSystemDefaultDevice();
     if (!device) {
         Log(LOG_E, @"Metal isn't supported on this device.");
-        self.view = [[PlatformView alloc] initWithFrame:self.view.frame];
+        self.view = [[UIView alloc] initWithFrame:self.view.frame];
         return;
     }
     view.metalLayer.device = device;
@@ -64,12 +65,12 @@ The implementation of the cross-platform game view controller.
         Log(LOG_E, @"The renderer couldn't be initialized.");
         return;
     }
+    self->_renderer = renderer;
+    Log(LOG_I, @"[MetalViewController] viewDidLoad, created renderer: %@", renderer);
 
     // Initialize the renderer-dependent view properties.
     view.metalLayer.pixelFormat = renderer.colorPixelFormat;
     view.metalLayer.maximumDrawableCount = 3;
-
-    self->_renderer = renderer;
 }
 
 - (void)waitToRenderTo:(nonnull CAMetalLayer *)layer {
@@ -95,46 +96,20 @@ The implementation of the cross-platform game view controller.
     [_renderer drawableResize:size];
 }
 
-- (void)shutdown {
-    [_renderer shutdown];
-}
-
 - (void)viewDidDisappear:(BOOL)animated {
     [super viewDidDisappear:animated];
 
-    Log(LOG_I, @"XXX MetalViewController viewDidDisappear");
+    Log(LOG_I, @"[MetalViewController] viewDidDisappear");
 
-    [_metalView shutdown];
+    [_renderer shutdown];
+    _renderer = nil;
 }
 
 #if TARGET_OS_IOS
-/// Hides the Home indicator button automatically.
+// Hides the Home indicator button automatically.
 - (BOOL)prefersHomeIndicatorAutoHidden {
     return YES;
 }
 #endif
 
-#if TARGET_OS_OSX
-/// Makes the view controller the first responder to receive keyboard events.
-- (void)viewDidAppear {
-    [_metalView.window makeFirstResponder:self];
-}
-
-/// Receives the keydown events to avoid system beeps.
-///
-/// The `GameInputKeyboardMouse` class handles keyboard events.
-- (void)keyDown:(NSEvent *)event {
-    // Reference the parameter to avoid an unused parameter warning.
-    (void)(event);
-}
-
-/// Receives the keyup events to avoid system beeps.
-///
-/// The `GameInputKeyboardMouse` class handles keyboard events.
-- (void)keyUp:(NSEvent *)event {
-    // Reference the parameter to avoid an unused parameter warning.
-    (void)(event);
-}
-#endif
-
 @end

VoidLink/Stats/ImGuiPlots.h

@@ -24,6 +24,7 @@ struct PlotDef {
 - (instancetype _Nonnull)init NS_UNAVAILABLE;
 + (instancetype _Nonnull)new NS_UNAVAILABLE;
 
+- (void)clearData;
 - (void)observeFloat:(int)plotId value:(CFTimeInterval)value;
 - (void)observeFloatReturnMetrics:(int)plotId value:(CFTimeInterval)value plotMetrics:(PlotMetrics * _Nullable)plotMetrics;
 

VoidLink/Stats/ImGuiPlots.mm

@@ -92,4 +92,12 @@
     }
 }
 
+- (void) clearData {
+    for (int i = 0; i < PlotCount; i++) {
+        if (_plots[i].buffer) {
+            [_plots[i].buffer clear];
+        }
+    }
+}
+
 @end

VoidLink/Stream/VideoDecoderRenderer.m

@@ -122,14 +122,13 @@ extern int ff_isom_write_av1c(AVIOContext *pb, const uint8_t *buf, int size,
     _view = view;
     _callbacks = callbacks;
     _streamAspectRatio = aspectRatio;
-
-    _parameterSetBuffers = [[NSMutableArray alloc] init];
-    _frameQueue = [FrameQueue sharedInstance];
-    [_frameQueue start];
     _maxRefreshRate = [[UIScreen mainScreen] maximumFramesPerSecond];
+    _parameterSetBuffers = [[NSMutableArray alloc] init];
 
     DataManager* dataMan = [[DataManager alloc] init];
 
+    _frameQueue = [FrameQueue sharedInstance];
+    [_frameQueue start];
     [_frameQueue setHighWaterMark:(int)[[dataMan getSettings].frameQueueSize integerValue]];
 
     [self reinitializeDisplayLayer];
@@ -149,6 +148,9 @@ extern int ff_isom_write_av1c(AVIOContext *pb, const uint8_t *buf, int size,
     self->_videoFormat = videoFormat;
     self->_frameRate = frameRate;
 
+    // reset plot data in case we've already used it for a previous renderer
+    [[ImGuiPlots sharedInstance] clearData];
+
     DataManager* dataMan = [[DataManager alloc] init];
     if ([[dataMan getSettings].renderingBackend integerValue] == RENDER_AVSB) {
         // PACING_MODE_VSYNC:
@@ -349,7 +351,7 @@ int DrSubmitDecodeUnit(PDECODE_UNIT decodeUnit);
 }
 - (void)cleanup
 {
-    [_frameQueue shutdown];
+    [_frameQueue stop];
 
     if (_renderingBackend == RENDER_AVSB) {
         [_displayLink invalidate];

VoidLink/Utility/FrameQueue.h

@@ -12,7 +12,7 @@ NS_ASSUME_NONNULL_BEGIN
 @property (nonatomic) FloatBuffer *frameDropMetrics;
 @property (nonatomic) int highWaterMark;
 @property (nonatomic, readonly) int maxCapacity;
-@property (atomic) BOOL isStopping;
+@property (atomic) BOOL paused;
 
 + (instancetype)sharedInstance;
 
@@ -27,8 +27,8 @@ NS_ASSUME_NONNULL_BEGIN
 - (CFTimeInterval)estimatedFramerate;
 - (int)currentSoftCap;
 - (void)waitForEnqueue;
-- (void)shutdown;
 - (void)start;
+- (void)stop;
 
 @end
 

VoidLink/Utility/FrameQueue.m

@@ -60,7 +60,7 @@
         _ptsCorrection     = CMTimeMake(0, 90000);
         _queueSizeHistory  = [[FloatBuffer alloc] initWithCapacity:64];
         _lock              = OS_UNFAIR_LOCK_INIT;
-        _isStopping        = NO;
+        _paused            = YES; // caller will call start()
 
 	    // ring buffer
 	    _capacity = _maxCapacity;
@@ -226,7 +226,7 @@
 
 // Allows the render loop to wait if the queue is empty
 - (void)waitForEnqueue {
-    while (!self.isStopping && [self isEmpty]) {
+    while (!self.paused && [self isEmpty]) {
         dispatch_time_t timeout = dispatch_time(DISPATCH_TIME_NOW, (int64_t)(0.1f * NSEC_PER_SEC)); // 100ms
         dispatch_semaphore_wait(_frameSemaphore, timeout);
     }
@@ -256,7 +256,7 @@
     CFTimeInterval deadline = start + timeout;
     int round = 0;
 
-    if (self.isStopping) {
+    if (self.paused) {
         return nil;
     }
 
@@ -287,15 +287,10 @@
     return [self count] == 0;
 }
 
-- (void)_clear_unsafe {
-    _head = _tail = _count = 0;
-    _frameDropMetrics = [[FloatBuffer alloc] initWithCapacity:512];
-}
-
-// The public clear method now safely calls the unsafe version.
 - (void)clear {
     os_unfair_lock_lock(&_lock);
-    [self _clear_unsafe];
+    _head = _tail = _count = 0;
+    _frameDropMetrics = [[FloatBuffer alloc] initWithCapacity:512];
     os_unfair_lock_unlock(&_lock);
 }
 
@@ -329,19 +324,17 @@
     return cap;
 }
 
-- (void)shutdown {
+- (void)stop {
     // new frames will no longer be coming in, make sure consumer side is not left waiting
-    self.isStopping = YES;
+    self.paused = YES;
-    Log(LOG_I, @"XXX FrameQueue shutting down");
+    Log(LOG_I, @"FrameQueue stopped");
     dispatch_semaphore_signal(_frameSemaphore);
 }
 
 - (void)start {
-    os_unfair_lock_lock(&_lock);
+    // (re)start for a new renderer
-    [self _clear_unsafe]; // Use the version without the lock
+    self.paused = NO;
-    self.isStopping = NO;
+    Log(LOG_I, @"FrameQueue started");
-    os_unfair_lock_unlock(&_lock);
-    Log(LOG_I, @"FrameQueue (re)started");
 }
 
 // For use with NSLog("%@", franeQueue);

VoidLink/ViewControllers/StreamFrameViewController.m

@@ -663,6 +663,7 @@
 
     if ([_settings.renderingBackend intValue] == RENDER_METAL) {
         // Metal view for video
+        Log(LOG_I, @"StreamFrameViewController creating MetalViewController");
         self.metalViewController = [[MetalViewController alloc] initWithFrame:self.view.bounds
                                                                     framerate:[self->_settings.framerate floatValue]
                                                                     enableHdr:self->_settings.enableHdr
@@ -745,7 +746,6 @@
             _inactivityTimer = nil;
         }
         if (self.metalViewController) {
-            [self.metalViewController shutdown];
             [self.metalViewController.view removeFromSuperview];
             [self.metalViewController removeFromParentViewController];
             self.metalViewController = nil;