More cleanup

* use single render command encoder for display for better performance
* Context handles all rendering and presentation

gfx/common/metal/Context.h

@@ -20,10 +20,18 @@
 
 @property (readonly) id<MTLDevice>        device;
 @property (readonly) id<MTLLibrary>       library;
+
+/*! @brief Returns the command buffer used for pre-render work,
+ * such as mip maps for applying filters
+ * */
+@property (readonly) id<MTLCommandBuffer> blitCommandBuffer;
+
 /*! @brief Returns the command buffer for the current frame */
 @property (readonly) id<MTLCommandBuffer> commandBuffer;
 @property (readonly) id<CAMetalDrawable>  nextDrawable;
-@property (readonly) id<MTLTexture>       renderTexture;
+
+/*! @brief Main render encoder to back buffer */
+@property (readonly) id<MTLRenderCommandEncoder> rce;
 
 - (instancetype)initWithDevice:(id<MTLDevice>)d
                          layer:(CAMetalLayer *)layer

gfx/common/metal/Context.m

@@ -16,18 +16,21 @@
 @end
 
 @interface Context()
-@property (readonly) id<MTLCommandBuffer> blitCommandBuffer;
 - (bool)_initConversionFilters;
 @end
 
 @implementation Context
 {
+   dispatch_semaphore_t _inflightSemaphore;
    id<MTLCommandQueue> _commandQueue;
    CAMetalLayer *_layer;
    id<CAMetalDrawable> _drawable;
    id<MTLSamplerState> _samplers[TEXTURE_FILTER_MIPMAP_NEAREST + 1];
    Filter *_filters[RPixelFormatCount]; // convert to bgra8888
    
+   // main render pass state
+   id<MTLRenderCommandEncoder> _rce;
+   
    id<MTLCommandBuffer> _blitCommandBuffer;
 }
 
@@ -37,6 +40,7 @@
 {
    if (self = [super init])
    {
+      _inflightSemaphore = dispatch_semaphore_create(MAX_INFLIGHT);
       _device = d;
       _layer = layer;
       _library = l;
@@ -63,10 +67,18 @@
       
       if (![self _initConversionFilters])
          return nil;
+      
+      if (![self _initMainState])
+         return nil;
    }
    return self;
 }
 
+- (bool)_initMainState
+{
+   return YES;
+}
+
 - (bool)_initConversionFilters
 {
    NSError *err = nil;
@@ -158,18 +170,13 @@
    return _drawable;
 }
 
-- (id<MTLTexture>)renderTexture
-{
-   return self.nextDrawable.texture;
-}
-
 - (void)convertFormat:(RPixelFormat)fmt from:(id<MTLBuffer>)src to:(id<MTLTexture>)dst
 {
    assert(dst.width * dst.height == src.length / RPixelFormatToBPP(fmt));
    assert(fmt >= 0 && fmt < RPixelFormatCount);
    Filter *conv = _filters[fmt];
    assert(conv != nil);
-   [conv apply:self.commandBuffer inBuf:src outTex:dst];
+   [conv apply:self.blitCommandBuffer inBuf:src outTex:dst];
 }
 
 - (id<MTLCommandBuffer>)blitCommandBuffer
@@ -182,9 +189,22 @@
 - (void)begin
 {
    assert(_commandBuffer == nil);
+   dispatch_semaphore_wait(_inflightSemaphore, DISPATCH_TIME_FOREVER);
    _commandBuffer = [_commandQueue commandBuffer];
 }
 
+- (id<MTLRenderCommandEncoder>)rce
+{
+   assert(_commandBuffer != nil);
+   if (_rce == nil)
+   {
+      MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
+      rpd.colorAttachments[0].texture = self.nextDrawable.texture;
+      _rce = [_commandBuffer renderCommandEncoderWithDescriptor:rpd];
+   }
+   return _rce;
+}
+
 - (void)end
 {
    assert(self->_commandBuffer != nil);
@@ -197,7 +217,20 @@
       _blitCommandBuffer = nil;
    }
    
+   if (_rce)
+   {
+      [_rce endEncoding];
+      _rce = nil;
+   }
+   
+   __block dispatch_semaphore_t inflight = _inflightSemaphore;
+   [_commandBuffer addCompletedHandler:^(id<MTLCommandBuffer> _) {
+      dispatch_semaphore_signal(inflight);
+   }];
+   
+   [_commandBuffer presentDrawable:self.nextDrawable];
    [_commandBuffer commit];
+   
    _commandBuffer = nil;
    _drawable = nil;
 }

gfx/common/metal/MenuDisplay.h

@@ -14,6 +14,7 @@
 @property (readwrite) MTLClearColor clearColor;
 
 - (instancetype)initWithDriver:(MetalDriver *)driver;
+- (void)drawPipeline:(menu_display_ctx_draw_t *)draw video:(video_frame_info_t *)video;
 - (void)draw:(menu_display_ctx_draw_t *)draw video:(video_frame_info_t *)video;
 
 #pragma mark - static methods

gfx/common/metal/MenuDisplay.m

@@ -166,6 +166,11 @@ static INLINE void write_quad4a(SpriteVertex *pv,
    }
 }
 
+- (void)drawPipeline:(menu_display_ctx_draw_t *)draw video:(video_frame_info_t *)video
+{
+
+}
+
 - (void)draw:(menu_display_ctx_draw_t *)draw video:(video_frame_info_t *)video
 {
    Texture *tex = (__bridge Texture *)(void *)draw->texture;
@@ -225,30 +230,20 @@ static INLINE void write_quad4a(SpriteVertex *pv,
 #endif
       default:
       {
-         MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
          if (_clearNextRender)
          {
-            rpd.colorAttachments[0].clearColor = _clearColor;
-            rpd.colorAttachments[0].loadAction = MTLLoadActionClear;
+            // TODO(sgc): draw quad to clear
             _clearNextRender = NO;
          }
-         else
-         {
-            rpd.colorAttachments[0].loadAction = MTLLoadActionLoad;
-         }
-         rpd.colorAttachments[0].storeAction = MTLStoreActionStore;
-         rpd.colorAttachments[0].texture = _context.nextDrawable.texture;
+   
+         id<MTLRenderCommandEncoder> rce = _context.rce;
          
-         id<MTLCommandBuffer> cb = _context.commandBuffer;
-         
-         id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:rpd];
          [rce setRenderPipelineState:[_driver getStockShader:VIDEO_SHADER_STOCK_BLEND blend:_blend]];
          [rce setVertexBytes:uniforms length:sizeof(*uniforms) atIndex:BufferIndexUniforms];
          [rce setVertexBytes:buf length:sizeof(buf) atIndex:BufferIndexPositions];
          [rce setFragmentTexture:tex.texture atIndex:TextureIndexColor];
          [rce setFragmentSamplerState:tex.sampler atIndex:SamplerIndexDraw];
          [rce drawPrimitives:MTLPrimitiveTypeTriangleStrip vertexStart:0 vertexCount:4];
-         [rce endEncoding];
          
          break;
       }

gfx/common/metal_common.h

@@ -46,7 +46,8 @@ extern MTLPixelFormat SelectOptimalPixelFormat(MTLPixelFormat fmt);
 
 @interface MetalMenu : NSObject
 
-@property (nonatomic, readwrite) BOOL enabled;
+@property (readonly) bool hasFrame;
+@property (readwrite) bool enabled;
 @property (readwrite) float alpha;
 
 - (void)updateFrame:(void const *)source;

gfx/common/metal_common.m

@@ -52,7 +52,6 @@
    
    video_info_t _video;
    
-   dispatch_semaphore_t _inflightSemaphore;
    id<MTLDevice> _device;
    id<MTLLibrary> _library;
    Context *_context;
@@ -62,7 +61,6 @@
    // render target layer state
    id<MTLRenderPipelineState> _t_pipelineState;
    id<MTLRenderPipelineState> _t_pipelineStateNoAlpha;
-   MTLRenderPassDescriptor *_t_rpd;
    
    id<MTLSamplerState> _samplerStateLinear;
    id<MTLSamplerState> _samplerStateNearest;
@@ -82,7 +80,6 @@
 {
    if (self = [super init])
    {
-      _inflightSemaphore = dispatch_semaphore_create(MAX_INFLIGHT);
       _device = MTLCreateSystemDefaultDevice();
       MetalView *view = (MetalView *)apple_platform.renderView;
       view.device = _device;
@@ -199,13 +196,6 @@
       }
    }
    
-   {
-      MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
-      rpd.colorAttachments[0].loadAction = MTLLoadActionDontCare;
-      rpd.colorAttachments[0].storeAction = MTLStoreActionStore;
-      _t_rpd = rpd;
-   }
-   
    {
       MTLSamplerDescriptor *sd = [MTLSamplerDescriptor new];
       _samplerStateNearest = [_device newSamplerStateWithDescriptor:sd];
@@ -214,6 +204,7 @@
       sd.magFilter = MTLSamplerMinMagFilterLinear;
       _samplerStateLinear = [_device newSamplerStateWithDescriptor:sd];
    }
+   
    return YES;
 }
 
@@ -230,7 +221,7 @@
    
    {
       MTLRenderPipelineDescriptor *psd = [MTLRenderPipelineDescriptor new];
-      psd.label = @"stock_blend";
+      psd.label = @"stock_no_blend";
       
       MTLRenderPipelineColorAttachmentDescriptor *ca = psd.colorAttachments[0];
       ca.pixelFormat = _layer.pixelFormat;
@@ -252,7 +243,8 @@
          RARCH_ERR("[Metal]: error creating pipeline state %s\n", err.localizedDescription.UTF8String);
          return NO;
       }
-      
+   
+      psd.label = @"stock_blend";
       ca.blendingEnabled = YES;
       _states[VIDEO_SHADER_STOCK_BLEND][1] = [_device newRenderPipelineStateWithDescriptor:psd error:&err];
       if (err != nil)
@@ -335,7 +327,6 @@
    
    assert(!_begin && !_end);
    _begin = YES;
-   dispatch_semaphore_wait(_inflightSemaphore, DISPATCH_TIME_FOREVER);
    [_context begin];
    [self _updateUniforms];
 }
@@ -346,18 +337,14 @@
    _begin = NO;
    _end = YES;
    
-   id<MTLCommandBuffer> cb = _context.commandBuffer;
-   cb.label = @"renderer cb";
+   id<MTLRenderCommandEncoder> rce = _context.rce;
    
    // draw back buffer
+   [rce pushDebugGroup:@"core frame"];
    [_frameView drawWithContext:_context];
    
-   id<CAMetalDrawable> drawable = _context.nextDrawable;
-   _t_rpd.colorAttachments[0].texture = drawable.texture;
-   
    if ((_frameView.drawState & ViewDrawStateEncoder) != 0)
    {
-      id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:_t_rpd];
       [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
       [rce setRenderPipelineState:_t_pipelineStateNoAlpha];
       if (_frameView.filter == RTextureFilterNearest)
@@ -369,27 +356,31 @@
          [rce setFragmentSamplerState:_samplerStateLinear atIndex:SamplerIndexDraw];
       }
       [_frameView drawWithEncoder:rce];
-      [rce endEncoding];
    }
+   [rce popDebugGroup];
 
 #if defined(HAVE_MENU)
    if (_menu.enabled)
    {
+      [rce pushDebugGroup:@"menu"];
       menu_driver_frame(video_info);
-      [_menu.view drawWithContext:_context];
-      id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:_t_rpd];
-      [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
-      [rce setRenderPipelineState:_t_pipelineState];
-      if (_menu.view.filter == RTextureFilterNearest)
+      
+      if (_menu.hasFrame)
       {
-         [rce setFragmentSamplerState:_samplerStateNearest atIndex:SamplerIndexDraw];
+         [_menu.view drawWithContext:_context];
+         [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
+         [rce setRenderPipelineState:_t_pipelineState];
+         if (_menu.view.filter == RTextureFilterNearest)
+         {
+            [rce setFragmentSamplerState:_samplerStateNearest atIndex:SamplerIndexDraw];
+         }
+         else
+         {
+            [rce setFragmentSamplerState:_samplerStateLinear atIndex:SamplerIndexDraw];
+         }
+         [_menu.view drawWithEncoder:rce];
       }
-      else
-      {
-         [rce setFragmentSamplerState:_samplerStateLinear atIndex:SamplerIndexDraw];
-      }
-      [_menu.view drawWithEncoder:rce];
-      [rce endEncoding];
+      [rce popDebugGroup];
    }
 #endif
 }
@@ -398,14 +389,6 @@
 {
    assert(!_begin && _end);
    _end = NO;
-   
-   id<MTLCommandBuffer> cb = _context.commandBuffer;
-   __block dispatch_semaphore_t inflight = _inflightSemaphore;
-   [cb addCompletedHandler:^(id<MTLCommandBuffer> _) {
-      dispatch_semaphore_signal(inflight);
-   }];
-   
-   [cb presentDrawable:_context.nextDrawable];
    [_context end];
 }
 
@@ -444,7 +427,7 @@
 {
    Context *_context;
    TexturedView *_view;
-   BOOL _enabled;
+   bool _enabled;
 }
 
 - (instancetype)initWithContext:(Context *)context
@@ -456,14 +439,19 @@
    return self;
 }
 
-- (void)setEnabled:(BOOL)enabled
+- (bool)hasFrame
+{
+   return _view != nil;
+}
+
+- (void)setEnabled:(bool)enabled
 {
    if (_enabled == enabled) return;
    _enabled = enabled;
    _view.visible = enabled;
 }
 
-- (BOOL)enabled
+- (bool)enabled
 {
    return _enabled;
 }
@@ -879,7 +867,7 @@ static vertex_t vertex_bytes[] = {
       }
    }
    
-   id<MTLCommandBuffer> cb = ctx.commandBuffer;
+   id<MTLCommandBuffer> cb = ctx.blitCommandBuffer;
    
    MTLRenderPassDescriptor *rpd = [MTLRenderPassDescriptor new];
    // rpd.colorAttachments[0].clearColor = MTLClearColorMake(0, 0, 0, 1.0);
@@ -888,18 +876,20 @@ static vertex_t vertex_bytes[] = {
    
    for (unsigned i = 0; i < _shader->passes; i++)
    {
+      id<MTLRenderCommandEncoder> rce = nil;
+      
       BOOL backBuffer = (_engine.pass[i].rt.view == nil);
       
       if (backBuffer)
       {
-         rpd.colorAttachments[0].texture = _context.nextDrawable.texture;
+         rce = _context.rce;
       }
       else
       {
          rpd.colorAttachments[0].texture = _engine.pass[i].rt.view;
+         rce = [cb renderCommandEncoderWithDescriptor:rpd];
       }
-      
-      id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:rpd];
+
 #if METAL_DEBUG
       rce.label = [NSString stringWithFormat:@"pass %d", i];
 #endif
@@ -962,17 +952,19 @@ static vertex_t vertex_bytes[] = {
       [rce setFragmentSamplerStates:samplers withRange:NSMakeRange(0, SLANG_NUM_BINDINGS)];
       [rce setVertexBytes:vertex_bytes length:sizeof(vertex_bytes) atIndex:4];
       [rce drawPrimitives:MTLPrimitiveTypeTriangleStrip vertexStart:0 vertexCount:4];
-      [rce endEncoding];
+      
+      if (!backBuffer)
+      {
+         [rce endEncoding];
+      }
+      
       _texture = _engine.pass[i].rt.view;
    }
+   
    if (_texture == nil)
-   {
       _drawState = ViewDrawStateContext;
-   }
    else
-   {
       _drawState = ViewDrawStateAll;
-   }
 }
 
 - (void)_updateRenderTargets

gfx/drivers_font/metal_raster_font.m

@@ -32,7 +32,6 @@
    id<MTLBuffer> _buffer;
    id<MTLTexture> _texture;
    
-   MTLRenderPassDescriptor *_rpd;
    id<MTLRenderPipelineState> _state;
    id<MTLSamplerState> _sampler;
    
@@ -163,12 +162,6 @@ static const NSUInteger kConstantAlignment = 4;
       }
    }
    
-   {
-      _rpd = [MTLRenderPassDescriptor renderPassDescriptor];
-      _rpd.colorAttachments[0].loadAction = MTLLoadActionDontCare;
-      _rpd.colorAttachments[0].storeAction = MTLStoreActionStore;
-   }
-   
    {
       MTLSamplerDescriptor *sd = [MTLSamplerDescriptor new];
       sd.minFilter = MTLSamplerMinMagFilterLinear;
@@ -339,10 +332,8 @@ static INLINE void write_quad6(SpriteVertex *pv,
 {
    NSUInteger start = _offset * sizeof(SpriteVertex);
    [_vert didModifyRange:NSMakeRange(start, sizeof(SpriteVertex) * _vertices)];
-   _rpd.colorAttachments[0].texture = _context.nextDrawable.texture;
    
-   id<MTLCommandBuffer> cb = _context.commandBuffer;
-   id<MTLRenderCommandEncoder> rce = [cb renderCommandEncoderWithDescriptor:_rpd];
+   id<MTLRenderCommandEncoder> rce = _context.rce;
    [rce pushDebugGroup:@"render fonts"];
    [rce setRenderPipelineState:_state];
    [rce setVertexBytes:&_uniforms length:sizeof(_uniforms) atIndex:BufferIndexUniforms];
@@ -351,7 +342,6 @@ static INLINE void write_quad6(SpriteVertex *pv,
    [rce setFragmentSamplerState:_sampler atIndex:SamplerIndexDraw];
    [rce drawPrimitives:MTLPrimitiveTypeTriangle vertexStart:0 vertexCount:_vertices];
    [rce popDebugGroup];
-   [rce endEncoding];
    
    _offset += _vertices;
    _vertices = 0;

menu/drivers_display/menu_display_metal.m

@@ -34,6 +34,7 @@ static void *menu_display_metal_get_default_mvp(video_frame_info_t *video_info)
    MetalDriver *md = GET_DRIVER(video_info);
    if (!md)
       return NULL;
+   
    return (void *)md.viewportMVP;
 }
 
@@ -67,6 +68,11 @@ static void menu_display_metal_draw(menu_display_ctx_draw_t *draw,
 
 static void menu_display_metal_draw_pipeline(menu_display_ctx_draw_t *draw, video_frame_info_t *video_info)
 {
+   MetalDriver *md = GET_DRIVER(video_info);
+   if (!md || !draw)
+      return;
+   
+   [md.display drawPipeline:draw video:video_info];
 }
 
 static void menu_display_metal_viewport(menu_display_ctx_draw_t *draw,
@@ -76,6 +82,7 @@ static void menu_display_metal_viewport(menu_display_ctx_draw_t *draw,
 
 static void menu_display_metal_restore_clear_color(void)
 {
+   // nothing to do
 }
 
 static void menu_display_metal_clear_color(menu_display_ctx_clearcolor_t *clearcolor,