Add HDR to Metal

Source/Core/VideoBackends/Metal/MTLMain.mm

@@ -164,8 +164,23 @@ void Metal::VideoBackend::PrepareWindow(WindowSystemInfo& wsi)
     return;
   NSView* view = static_cast<NSView*>(wsi.render_surface);
   CAMetalLayer* layer = [CAMetalLayer layer];
+
+  Util::PopulateBackendInfo(&g_Config);
+
+  if (g_Config.backend_info.bSupportsHDROutput && g_Config.bHDR)
+  {
+    [layer setWantsExtendedDynamicRangeContent:YES];
+    [layer setPixelFormat:MTLPixelFormatRGBA16Float];
+
+    const CFStringRef name = kCGColorSpaceExtendedLinearSRGB;
+    CGColorSpaceRef colorspace = CGColorSpaceCreateWithName(name);
+    [layer setColorspace:colorspace];
+    CGColorSpaceRelease(colorspace);
+  }
+
   [view setWantsLayer:YES];
   [view setLayer:layer];
+
   wsi.render_surface = layer;
 #endif
 }

Source/Core/VideoBackends/Metal/MTLUtil.h

@@ -3,7 +3,9 @@
 
 #pragma once
 
+#include <AppKit/NSScreen.h>
 #include <Metal/Metal.h>
+
 #include <vector>
 
 #include "VideoCommon/AbstractShader.h"

Source/Core/VideoBackends/Metal/MTLUtil.mm

@@ -77,6 +77,8 @@ void Metal::Util::PopulateBackendInfo(VideoConfig* config)
   config->backend_info.bSupportsPartialMultisampleResolve = false;
   config->backend_info.bSupportsDynamicVertexLoader = true;
   config->backend_info.bSupportsVSLinePointExpand = true;
+  config->backend_info.bSupportsHDROutput =
+      1.0 < [[NSScreen deepestScreen] maximumPotentialExtendedDynamicRangeColorComponentValue];
 }
 
 void Metal::Util::PopulateBackendInfoAdapters(VideoConfig* config,