fix(Metal): improve shader stability

* use MTKView, which handles layer and scaling changes automatically
  between displays

gfx/common/metal/Renderer.h

@@ -12,7 +12,6 @@
 #import "Context.h"
 #import "PixelConverter.h"
 
-@class ViewDescriptor;
 @protocol View;
 
 @interface Renderer : NSObject

gfx/common/metal/Renderer.m

@@ -113,9 +113,7 @@
 
    {
       MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
-      // Cornflower Blue #58BAF9
+      rpd.colorAttachments[0].loadAction = MTLLoadActionDontCare;
-      //rpd.colorAttachments[0].clearColor = MTLClearColorMake(0x58 / 255.0, 0xba / 255.0, 0xf9 / 255.0, 1.0);
-      rpd.colorAttachments[0].loadAction = MTLLoadActionLoad;
       rpd.colorAttachments[0].storeAction = MTLStoreActionStore;
       _t_rpd = rpd;
    }
@@ -163,49 +161,60 @@
 
    for (id<View> v in _views) {
       if (!v.visible) continue;
-      if ([v respondsToSelector:@selector(prepareFrame:)]) {
+      if ([v respondsToSelector:@selector(drawWithContext:)]) {
-         [v prepareFrame:_context];
+         [v drawWithContext:_context];
       }
    }
-
+   
-   id<CAMetalDrawable> drawable = _context.nextDrawable;
+   BOOL pendingDraws = NO;
-   _t_rpd.colorAttachments[0].texture = drawable.texture;
-
-   id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:_t_rpd];
-   [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
-
    for (id<View> v in _views) {
-      if (!v.visible ||
+      if (v.visible && (v.drawState & ViewDrawStateEncoder) != 0) {
-          ![v respondsToSelector:@selector(drawWithEncoder:)]) {
+         pendingDraws = YES;
-         continue;
+         break;
       }
-
-      // set view state
-      if (v.format == RPixelFormatBGRX8Unorm) {
-         [rce setRenderPipelineState:_t_pipelineStateNoAlpha];
-      }
-      else {
-         [rce setRenderPipelineState:_t_pipelineState];
-      }
-
-      if (v.filter == RTextureFilterNearest) {
-         [rce setFragmentSamplerState:_samplerStateNearest atIndex:SamplerIndexDraw];
-      }
-      else {
-         [rce setFragmentSamplerState:_samplerStateLinear atIndex:SamplerIndexDraw];
-      }
-
-      [v drawWithEncoder:rce];
    }
-
+   
-   [rce endEncoding];
+   if (pendingDraws) {
+      id<CAMetalDrawable> drawable = _context.nextDrawable;
+      _t_rpd.colorAttachments[0].texture = drawable.texture;
+      
+      id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:_t_rpd];
+      [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
+      
+      for (id<View> v in _views) {
+         if (!v.visible ||
+             ![v respondsToSelector:@selector(drawWithEncoder:)] ||
+             (v.drawState & ViewDrawStateEncoder) == 0) {
+            continue;
+         }
+         
+         // set view state
+         if (v.format == RPixelFormatBGRX8Unorm || v.format == RPixelFormatB5G6R5Unorm) {
+            [rce setRenderPipelineState:_t_pipelineStateNoAlpha];
+         }
+         else {
+            [rce setRenderPipelineState:_t_pipelineState];
+         }
+         
+         if (v.filter == RTextureFilterNearest) {
+            [rce setFragmentSamplerState:_samplerStateNearest atIndex:SamplerIndexDraw];
+         }
+         else {
+            [rce setFragmentSamplerState:_samplerStateLinear atIndex:SamplerIndexDraw];
+         }
+         
+         [v drawWithEncoder:rce];
+      }
+      
+      [rce endEncoding];
+   }
 
    __block dispatch_semaphore_t inflight = _inflightSemaphore;
    [cb addCompletedHandler:^(id<MTLCommandBuffer> _) {
       dispatch_semaphore_signal(inflight);
    }];
 
-   [cb presentDrawable:drawable];
+   [cb presentDrawable:_context.nextDrawable];
    [_context end];
 }
 

gfx/common/metal/RendererCommon.h

@@ -11,33 +11,34 @@
 
 #import <Foundation/Foundation.h>
 
+// TODO(sgc): implement triple buffering
 /*! @brief maximum inflight frames */
-#define MAX_INFLIGHT 3
+#define MAX_INFLIGHT 1
 
 #pragma mark - Pixel Formats
 
 typedef NS_ENUM(NSUInteger, RPixelFormat) {
-    
+   
-    RPixelFormatInvalid,
+   RPixelFormatInvalid,
-    
+   
-    /* 16-bit formats */
+   /* 16-bit formats */
-    RPixelFormatBGRA4Unorm,
+   RPixelFormatBGRA4Unorm,
-    RPixelFormatB5G6R5Unorm,
+   RPixelFormatB5G6R5Unorm,
-    
+   
-    RPixelFormatBGRA8Unorm,
+   RPixelFormatBGRA8Unorm,
-    RPixelFormatBGRX8Unorm,
+   RPixelFormatBGRX8Unorm, // RetroArch XRGB
-    
+   
-    RPixelFormatCount,
+   RPixelFormatCount,
 };
 
 extern NSUInteger RPixelFormatToBPP(RPixelFormat format);
 extern NSString *NSStringFromRPixelFormat(RPixelFormat format);
 
 typedef NS_ENUM(NSUInteger, RTextureFilter) {
-    RTextureFilterNearest,
+   RTextureFilterNearest,
-    RTextureFilterLinear,
+   RTextureFilterLinear,
-    
+   
-    RTextureFilterCount,
+   RTextureFilterCount,
 };
 
 #endif /* RendererCommon_h */

gfx/common/metal/TexturedView.h

@@ -13,11 +13,12 @@
 @property (readwrite) BOOL visible;
 @property (readwrite) CGRect frame;
 @property (readwrite) CGSize size;
+@property (readonly) ViewDrawState drawState;
 
 - (instancetype)initWithDescriptor:(ViewDescriptor *)td renderer:(Renderer *)renderer;
 
-- (void)prepareFrame:(Context *)ctx;
+- (void)drawWithContext:(Context *)ctx;
-- (void)updateFrame:(void const *)src pitch:(NSUInteger)pitch;
 - (void)drawWithEncoder:(id<MTLRenderCommandEncoder>)rce;
+- (void)updateFrame:(void const *)src pitch:(NSUInteger)pitch;
 
 @end

gfx/common/metal/TexturedView.m

@@ -35,6 +35,11 @@
       _filter = d.filter;
       _context = r.context;
       _visible = YES;
+      if (_format == RPixelFormatBGRA8Unorm || _format == RPixelFormatBGRX8Unorm) {
+         _drawState = ViewDrawStateEncoder;
+      } else {
+         _drawState = ViewDrawStateAll;
+      }
       self.size = d.size;
       self.frame = CGRectMake(0, 0, 1, 1);
    }
@@ -113,7 +118,7 @@
    _pixelsDirty = NO;
 }
 
-- (void)prepareFrame:(Context *)ctx {
+- (void)drawWithContext:(Context *)ctx {
    [self _convertFormat];
 }
 

gfx/common/metal/View.h

@@ -10,6 +10,15 @@
 #import <Foundation/Foundation.h>
 #import <Metal/Metal.h>
 
+typedef NS_ENUM(NSInteger, ViewDrawState)
+{
+   ViewDrawStateNone    = 0x00,
+   ViewDrawStateContext = 0x01,
+   ViewDrawStateEncoder = 0x02,
+   
+   ViewDrawStateAll     = 0x03,
+};
+
 @protocol View<NSObject>
 
 @property (readonly) RPixelFormat format;
@@ -17,9 +26,10 @@
 @property (readwrite) BOOL visible;
 @property (readwrite) CGRect frame;
 @property (readwrite) CGSize size;
+@property (readonly) ViewDrawState drawState;
 
 @optional
-- (void)prepareFrame:(Context *)ctx;
+- (void)drawWithContext:(Context *)ctx;
 - (void)drawWithEncoder:(id<MTLRenderCommandEncoder>)rce;
 
 @end

gfx/common/metal_common.h

@@ -9,6 +9,7 @@
 #define METAL_COMMON_H__
 
 #import <Metal/Metal.h>
+#import <MetalKit/MetalKit.h>
 #import "metal/metal_common.h"
 
 #include <retro_common_api.h>
@@ -20,6 +21,9 @@
 
 RETRO_BEGIN_DECLS
 
+extern MTLPixelFormat glslang_format_to_metal(glslang_format fmt);
+extern MTLPixelFormat SelectOptimalPixelFormat(MTLPixelFormat fmt);
+
 #pragma mark - Classes
 
 @interface FrameView : NSObject<View>
@@ -29,6 +33,7 @@ RETRO_BEGIN_DECLS
 @property (readwrite) BOOL visible;
 @property (readwrite) CGRect frame;
 @property (readwrite) CGSize size;
+@property (readonly) ViewDrawState drawState;
 @property (readonly) struct video_shader* shader;
 
 @property (readwrite) uint64_t         frameCount;
@@ -53,7 +58,7 @@ RETRO_BEGIN_DECLS
              filter:(RTextureFilter)filter;
 @end
 
-@interface MetalDriver : NSObject<PlatformDelegate>
+@interface MetalDriver : NSObject<MTKViewDelegate>
 
 @property (readonly) video_viewport_t* viewport;
 @property (readwrite) bool             keepAspect;
@@ -71,11 +76,6 @@ RETRO_BEGIN_DECLS
 /*! @brief setNeedsResize triggers a display resize */
 - (void)setNeedsResize;
 
-- (void)viewDidUpdateFrame:(NSRect)rect;
-
-
-#pragma mark - Menu APIs
-
 @end
 
 RETRO_END_DECLS

gfx/common/metal_common.m

@@ -32,7 +32,7 @@
 @property (readwrite) video_viewport_t *viewport;
 
 - (instancetype)initWithDescriptor:(ViewDescriptor *)td renderer:(Renderer *)renderer;
-- (void)prepareFrame:(Context *)ctx;
+- (void)drawWithContext:(Context *)ctx;
 - (void)drawWithEncoder:(id<MTLRenderCommandEncoder>)rce;
 
 @end
@@ -72,32 +72,19 @@
    }
 }
 
-#pragma mark - swap chain
-
-- (void)viewDidUpdateFrame:(NSRect)rect
-{
-   RARCH_LOG("[MetalDriver] viewDidUpdateFrame %s\n", NSStringFromRect(rect).UTF8String);
-   _viewport->full_width = (unsigned int)rect.size.width;
-   _viewport->full_height = (unsigned int)rect.size.height;
-   video_driver_set_size(&_viewport->full_width, &_viewport->full_height);
-   resize_chain = YES;
-}
-
-
 #pragma mark - video
 
 - (void)setVideo:(const video_info_t *)video
 {
    _video = *video;
-   _viewport->full_width = _video.width;
-   _viewport->full_height = _video.height;
 
    if (!_renderer) {
       id<MTLDevice> device = MTLCreateSystemDefaultDevice();
       _device = device;
-      NSView *view = (NSView *)apple_platform.renderView;
+      MetalView *view = (MetalView *)apple_platform.renderView;
+      view.device = device;
       CAMetalLayer *layer = (CAMetalLayer *)view.layer;
-      layer.device = device;
+      //layer.device = device;
       _renderer = [[Renderer alloc] initWithDevice:device layer:layer];
       _menu.renderer = _renderer;
    }
@@ -119,11 +106,6 @@
 
 - (void)beginFrame
 {
-   if (resize_chain) {
-      [_renderer drawableSizeWillChange:CGSizeMake(_viewport->full_width, _viewport->full_height)];
-      resize_chain = NO;
-   }
-
    video_driver_update_viewport(_viewport, NO, _keepAspect);
 
    [_renderer beginFrame];
@@ -139,6 +121,21 @@
    // TODO(sgc): resize all drawables
 }
 
+#pragma mark - MTKViewDelegate
+
+- (void)mtkView:(MTKView *)view drawableSizeWillChange:(CGSize)size {
+   RARCH_LOG("[MetalDriver] drawableSizeWillChange: %s\n", NSStringFromSize(size).UTF8String);
+   _viewport->full_width = (unsigned int)size.width;
+   _viewport->full_height = (unsigned int)size.height;
+   video_driver_set_size(&_viewport->full_width, &_viewport->full_height);
+   [_renderer drawableSizeWillChange:size];
+   video_driver_update_viewport(_viewport, NO, _keepAspect);
+}
+
+- (void)drawInMTKView:(MTKView *)view {
+
+}
+
 extern inline matrix_float4x4 matrix_proj_ortho1(float left, float right, float top, float bottom)
 {
    float near = 0;
@@ -292,12 +289,18 @@ typedef struct ALIGN(16)
       _format = d.format;
       _bpp = RPixelFormatToBPP(_format);
       _filter = d.filter;
+      if (_format == RPixelFormatBGRA8Unorm || _format == RPixelFormatBGRX8Unorm) {
+         _drawState = ViewDrawStateEncoder;
+      } else {
+         _drawState = ViewDrawStateAll;
+      }
       _visible = YES;
       _engine.mvp = matrix_proj_ortho1(0, 1, 0, 1);
       [self _initSamplers];
 
       self.size = d.size;
       self.frame = CGRectMake(0, 0, 1, 1);
+      resize_render_targets = YES;
    }
    return self;
 }
@@ -425,7 +428,6 @@ typedef struct ALIGN(16)
          if (init_history)
             [self _initHistory];
          else {
-            // TODO(sgc): change to ring buffer?
             int k;
             /* todo: what about frame-duping ?
              * maybe clone d3d10_texture_t with AddRef */
@@ -546,7 +548,7 @@ static vertex_t vertex_bytes[] = {
    }
 }
 
-- (void)prepareFrame:(Context *)ctx
+- (void)drawWithContext:(Context *)ctx
 {
    _texture = _engine.frame.texture[0].view;
    [self _convertFormat];
@@ -567,15 +569,15 @@ static vertex_t vertex_bytes[] = {
 
    MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
    rpd.colorAttachments[0].clearColor = MTLClearColorMake(0, 0, 0, 1.0);
-   rpd.colorAttachments[0].loadAction = MTLLoadActionDontCare;
+   rpd.colorAttachments[0].loadAction = MTLLoadActionClear;
    rpd.colorAttachments[0].storeAction = MTLStoreActionStore;
 
    BOOL firstPass = YES;
    
    for (unsigned i = 0; i < _shader->passes; i++) {
-      BOOL lastPass  = i == _shader->passes - 1;
+      BOOL backBuffer = (_engine.pass[i].rt.view == nil);
 
-      if (lastPass) {
+      if (backBuffer) {
          rpd.colorAttachments[0].texture = _context.nextDrawable.texture;
       }
       else {
@@ -630,7 +632,7 @@ static vertex_t vertex_bytes[] = {
          texture_sem++;
       }
 
-      if (lastPass) {
+      if (backBuffer) {
          [rce setViewport:_engine.frame.viewport];
       }
       else {
@@ -645,7 +647,11 @@ static vertex_t vertex_bytes[] = {
       [rce endEncoding];
       _texture = _engine.pass[i].rt.view;
    }
-   _texture = nil;
+   if (_texture == nil) {
+      _drawState = ViewDrawStateContext;
+   } else {
+      _drawState = ViewDrawStateAll;
+   }
 }
 
 - (void)_updateRenderTargets
@@ -712,15 +718,17 @@ static vertex_t vertex_bytes[] = {
       }
 
       RARCH_LOG("[Metal]: Updating framebuffer size %u x %u.\n", width, height);
-
+      MTLPixelFormat fmt = SelectOptimalPixelFormat(glslang_format_to_metal(_engine.pass[i].semantics.format));
-      if (i != (_shader->passes - 1)) {
+      if ((i != (_shader->passes - 1)) ||
-
+          (width != _viewport->width) || (height != _viewport->height) ||
+          fmt != MTLPixelFormatBGRA8Unorm)
+      {
          _engine.pass[i].viewport.width = width;
          _engine.pass[i].viewport.height = height;
          _engine.pass[i].viewport.znear = 0.0;
          _engine.pass[i].viewport.zfar = 1.0;
 
-         MTLTextureDescriptor *td = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:MTLPixelFormatBGRA8Unorm
+         MTLTextureDescriptor *td = [MTLTextureDescriptor texture2DDescriptorWithPixelFormat:fmt
                                                                                        width:width
                                                                                       height:height
                                                                                    mipmapped:false];
@@ -823,8 +831,16 @@ static vertex_t vertex_bytes[] = {
          if (!slang_process(shader, i, RARCH_SHADER_METAL, 20000, &semantics_map, &_engine.pass[i].semantics))
             return NO;
 
+#ifdef DEBUG
+         bool save_msl = true;
+#else
+         bool save_msl = false;
+#endif
+         NSString *vs_src = [NSString stringWithUTF8String:shader->pass[i].source.string.vertex];
+         NSString *fs_src = [NSString stringWithUTF8String:shader->pass[i].source.string.fragment];
+
+         // vertex descriptor
          @try {
-            // vertex descriptor
             MTLVertexDescriptor *vd = [MTLVertexDescriptor new];
             vd.attributes[0].offset = offsetof(vertex_t, pos);
             vd.attributes[0].format = MTLVertexFormatFloat4;
@@ -839,8 +855,11 @@ static vertex_t vertex_bytes[] = {
             psd.label = [NSString stringWithFormat:@"pass %d", i];
 
             MTLRenderPipelineColorAttachmentDescriptor *ca = psd.colorAttachments[0];
-            ca.pixelFormat = MTLPixelFormatBGRA8Unorm;
+            
-            ca.blendingEnabled = YES;
+            ca.pixelFormat = SelectOptimalPixelFormat(glslang_format_to_metal(_engine.pass[i].semantics.format));
+
+            // TODO(sgc): confirm we never need blending for render passes
+            ca.blendingEnabled = NO;
             ca.sourceAlphaBlendFactor = MTLBlendFactorSourceAlpha;
             ca.sourceRGBBlendFactor = MTLBlendFactorSourceAlpha;
             ca.destinationAlphaBlendFactor = MTLBlendFactorOneMinusSourceAlpha;
@@ -848,19 +867,18 @@ static vertex_t vertex_bytes[] = {
 
             psd.sampleCount = 1;
             psd.vertexDescriptor = vd;
-            NSString *vs_src = [NSString stringWithUTF8String:shader->pass[i].source.string.vertex];
-            NSLog(@"vertex function:\n%@", vs_src);
-            NSString *fs_src = [NSString stringWithUTF8String:shader->pass[i].source.string.fragment];
-            NSLog(@"fragment function:\n%@", fs_src);
 
             NSError *err;
             id<MTLLibrary> lib = [_context.device newLibraryWithSource:vs_src options:nil error:&err];
             if (err != nil) {
                if (lib == nil) {
+                  save_msl = true;
                   RARCH_ERR("Metal]: unable to compile vertex shader: %s\n", err.localizedDescription.UTF8String);
                   return NO;
                }
+#if DEBUG
                RARCH_WARN("[Metal]: warnings compiling vertex shader: %s\n", err.localizedDescription.UTF8String);
+#endif
             }
 
             psd.vertexFunction = [lib newFunctionWithName:@"main0"];
@@ -868,16 +886,20 @@ static vertex_t vertex_bytes[] = {
             lib = [_context.device newLibraryWithSource:fs_src options:nil error:&err];
             if (err != nil) {
                if (lib == nil) {
+                  save_msl = true;
                   RARCH_ERR("Metal]: unable to compile fragment shader: %s\n", err.localizedDescription.UTF8String);
                   return NO;
                }
+#if DEBUG
                RARCH_WARN("[Metal]: warnings compiling fragment shader: %s\n", err.localizedDescription.UTF8String);
+#endif
             }
             psd.fragmentFunction = [lib newFunctionWithName:@"main0"];
 
             STRUCT_ASSIGN(_engine.pass[i]._state,
                           [_context.device newRenderPipelineStateWithDescriptor:psd error:&err]);
             if (err != nil) {
+               save_msl = true;
                RARCH_ERR("error creating pipeline state: %s", err.localizedDescription.UTF8String);
                return NO;
             }
@@ -892,6 +914,29 @@ static vertex_t vertex_bytes[] = {
                STRUCT_ASSIGN(_engine.pass[i].buffers[j], buf);
             }
          } @finally {
+            if (save_msl) {
+               RARCH_LOG("[Metal]: saving metal shader files\n");
+
+               NSError *err = nil;
+               NSString *basePath = [[NSString stringWithUTF8String:shader->pass[i].source.path] stringByDeletingPathExtension];
+               [vs_src writeToFile:[basePath stringByAppendingPathExtension:@"vs.metal"]
+                        atomically:NO
+                          encoding:NSStringEncodingConversionAllowLossy
+                             error:&err];
+               if (err != nil) {
+                  RARCH_ERR("[Metal]: unable to save vertex shader source: %s\n", err.localizedDescription.UTF8String);
+               }
+               
+               err = nil;
+               [fs_src writeToFile:[basePath stringByAppendingPathExtension:@"fs.metal"]
+                        atomically:NO
+                          encoding:NSStringEncodingConversionAllowLossy
+                             error:&err];
+               if (err != nil) {
+                  RARCH_ERR("[Metal]: unable to save fragment shader source: %s\n", err.localizedDescription.UTF8String);
+               }
+            }
+
             free(shader->pass[i].source.string.vertex);
             free(shader->pass[i].source.string.fragment);
 
@@ -945,3 +990,67 @@ static vertex_t vertex_bytes[] = {
 }
 
 @end
+
+MTLPixelFormat glslang_format_to_metal(glslang_format fmt)
+{
+#undef FMT2
+#define FMT2(x,y) case SLANG_FORMAT_##x: return MTLPixelFormat##y
+   
+   switch (fmt)
+   {
+         FMT2(R8_UNORM, R8Unorm);
+         FMT2(R8_SINT, R8Sint);
+         FMT2(R8_UINT, R8Uint);
+         FMT2(R8G8_UNORM, RG8Unorm);
+         FMT2(R8G8_SINT, RG8Sint);
+         FMT2(R8G8_UINT, RG8Uint);
+         FMT2(R8G8B8A8_UNORM, RGBA8Unorm);
+         FMT2(R8G8B8A8_SINT, RGBA8Sint);
+         FMT2(R8G8B8A8_UINT, RGBA8Uint);
+         FMT2(R8G8B8A8_SRGB, RGBA8Unorm_sRGB);
+         
+         FMT2(A2B10G10R10_UNORM_PACK32, RGB10A2Unorm);
+         FMT2(A2B10G10R10_UINT_PACK32, RGB10A2Uint);
+         
+         FMT2(R16_UINT, R16Uint);
+         FMT2(R16_SINT, R16Sint);
+         FMT2(R16_SFLOAT, R16Float);
+         FMT2(R16G16_UINT, RG16Uint);
+         FMT2(R16G16_SINT, RG16Sint);
+         FMT2(R16G16_SFLOAT, RG16Float);
+         FMT2(R16G16B16A16_UINT, RGBA16Uint);
+         FMT2(R16G16B16A16_SINT, RGBA16Sint);
+         FMT2(R16G16B16A16_SFLOAT, RGBA16Float);
+         
+         FMT2(R32_UINT, R32Uint);
+         FMT2(R32_SINT, R32Sint);
+         FMT2(R32_SFLOAT, R32Float);
+         FMT2(R32G32_UINT, RG32Uint);
+         FMT2(R32G32_SINT, RG32Sint);
+         FMT2(R32G32_SFLOAT, RG32Float);
+         FMT2(R32G32B32A32_UINT, RGBA32Uint);
+         FMT2(R32G32B32A32_SINT, RGBA32Sint);
+         FMT2(R32G32B32A32_SFLOAT, RGBA32Float);
+         
+      case SLANG_FORMAT_UNKNOWN:
+      default:
+         break;
+   }
+#undef FMT2
+   return MTLPixelFormatInvalid;
+}
+
+MTLPixelFormat SelectOptimalPixelFormat(MTLPixelFormat fmt)
+{
+   switch (fmt)
+   {
+      case MTLPixelFormatRGBA8Unorm:
+         return MTLPixelFormatBGRA8Unorm;
+         
+      case MTLPixelFormatRGBA8Unorm_sRGB:
+         return MTLPixelFormatBGRA8Unorm_sRGB;
+         
+      default:
+         return fmt;
+   }
+}

gfx/drivers/metal.m

@@ -53,13 +53,14 @@ static void *metal_init(const video_info_t *video,
    gfx_ctx_mode_t mode;
 
    [apple_platform setViewType:APPLE_VIEW_TYPE_METAL];
-
    MetalDriver *md = [MetalDriver new];
    if (md == nil) {
       return NULL;
    }
+   MetalView *view = (MetalView *)apple_platform.renderView;
+   view.delegate = md;
 
-   apple_platform.delegate = md;
+   md.keepAspect = video->force_aspect;
 
    RARCH_LOG("[Metal]: Detecting screen resolution %ux%u.\n", video->width, video->height);
 
@@ -67,8 +68,8 @@ static void *metal_init(const video_info_t *video,
    mode.height = video->height;
    mode.fullscreen = video->fullscreen;
 
-   [apple_platform setVideoMode:mode];
    [md setVideo:video];
+   [apple_platform setVideoMode:mode];
 
    *input = NULL;
    *input_data = NULL;

ui/drivers/cocoa/cocoa_common.h

@@ -36,22 +36,16 @@ typedef enum apple_view_type {
    APPLE_VIEW_TYPE_METAL,
 } apple_view_type_t;
 
-@protocol PlatformDelegate
 #ifdef HAVE_METAL
-@optional
+#import <MetalKit/MetalKit.h>
-- (void)viewDidUpdateFrame:(NSRect)rect;
+
-#endif
+@interface MetalView : MTKView
 @end
 
+#endif
+
 @protocol ApplePlatform
 
-@property (readwrite,retain) id<PlatformDelegate> delegate;
-
-/*!
- @brief viewHandle returns an appropriate handle for the current view type
- */
-@property (readonly) id viewHandle;
-
 /*! @brief renderView returns the current render view based on the viewType */
 @property (readonly) id renderView;
 

ui/drivers/cocoa/cocoa_common.m

@@ -19,9 +19,6 @@
 #include "cocoa_common.h"
 #ifdef HAVE_COCOA
 #include "../ui_cocoa.h"
-#ifdef HAVE_VULKAN
-#import <QuartzCore/CAMetalLayer.h>
-#endif
 #endif
 
 #include <retro_assert.h>
@@ -46,6 +43,21 @@
 #include "../../../location/location_driver.h"
 #include "../../../camera/camera_driver.h"
 
+#ifdef HAVE_METAL
+@implementation MetalView
+
+- (void)keyDown:(NSEvent*)theEvent
+{
+}
+
+/* Stop the annoying sound when pressing a key. */
+- (BOOL)acceptsFirstResponder
+{
+   return YES;
+}
+@end
+#endif
+
 static CocoaView* g_instance;
 
 #if defined(HAVE_COCOA)
@@ -96,15 +108,13 @@ void *glkitview_init(void);
 }
 
 #if defined(HAVE_COCOA)
+- (BOOL)layer:(CALayer *)layer shouldInheritContentsScale:(CGFloat)newScale fromWindow:(NSWindow *)window {
+   return YES;
+}
+
 - (void)setFrame:(NSRect)frameRect
 {
    [super setFrame:frameRect];
-
-   if (apple_platform.delegate != nil)
-   {
-      [apple_platform.delegate viewDidUpdateFrame:frameRect];
-   }
-
    cocoagl_gfx_ctx_update();
 }
 

ui/drivers/ui_cocoa.m

@@ -53,7 +53,6 @@ id<ApplePlatform> apple_platform;
    NSWindow* _window;
    apple_view_type_t _vt;
    NSView* _renderView;
-   id<PlatformDelegate> _delegate;
 }
 
 @property (nonatomic, retain) NSWindow IBOutlet* window;
@@ -259,9 +258,9 @@ static char** waiting_argv;
       case APPLE_VIEW_TYPE_METAL:
 #if defined(HAVE_METAL) || defined(HAVE_VULKAN)
       {
-         NSView *v = [CocoaView get];
+         MetalView *v = [MetalView new];
-         v.wantsLayer = YES;
+         v.paused = YES;
-         v.layer = CAMetalLayer.layer;
+         v.enableSetNeedsDisplay = NO;
          _renderView = v;
       }
 #endif
@@ -280,7 +279,7 @@ static char** waiting_argv;
    
    _renderView.autoresizingMask = NSViewWidthSizable | NSViewHeightSizable;
    _renderView.frame = self.window.contentView.bounds;
-   
+
    [self.window.contentView addSubview:_renderView];
    [self.window makeFirstResponder:_renderView];
 }
@@ -293,18 +292,6 @@ static char** waiting_argv;
    return _renderView;
 }
 
-- (id)delegate {
-   return _delegate;
-}
-
-- (void)setDelegate:(id<PlatformDelegate>)delegate {
-   _delegate = delegate;
-}
-
-- (id)viewHandle {
-   return nil;
-}
-
 - (bool)hasFocus {
    return [NSApp isActive];
 }