Metal sync interval support (#2187)

* Metal sync interval support
Add shader name to SRGPool for debugging purposes
Set default value of rpi_vsync_interval to 1

Signed-off-by: moudgils <moudgils@amazon.com>

Gems/Atom/RHI/Metal/Code/Source/Platform/Mac/RHI/Metal_RHI_Mac.cpp

@@ -43,11 +43,36 @@ namespace Platform
         }
         return physicalDeviceList;
     }
-
-    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval)
+    
+    float GetRefreshRate()
     {
-        AZ_UNUSED(syncInterval);
-        [mtlCommandBuffer presentDrawable:drawable];
+        CGDirectDisplayID display = CGMainDisplayID();
+        CGDisplayModeRef currentMode = CGDisplayCopyDisplayMode(display);
+        return CGDisplayModeGetRefreshRate(currentMode);
+    }
+
+    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval, float refreshRate)
+    {
+        bool framePresented = false;
+        
+        //seconds per frame (1/refreshrate) * num frames (sync interval)
+        float presentAfterMinimumDuration = syncInterval / refreshRate;
+        
+#if defined(__MAC_10_15_4)
+        if(@available(macOS 10.15.4, *))
+        {
+            if(presentAfterMinimumDuration > 0.0f)
+            {
+                [mtlCommandBuffer presentDrawable:drawable afterMinimumDuration:presentAfterMinimumDuration];
+                framePresented = true;
+            }
+        }
+#endif
+
+        if(!framePresented)
+        {
+            [mtlCommandBuffer presentDrawable:drawable];
+        }
     }
 
     CGRect GetScreenBounds(NativeWindowType* nativeWindow)

Gems/Atom/RHI/Metal/Code/Source/Platform/iOS/RHI/Metal_RHI_iOS.cpp

@@ -29,13 +29,19 @@ namespace Platform
         return physicalDeviceList;
     }
 
-    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval)
+    float GetRefreshRate()
     {
-        bool hasPresentAfterMinimumDuration = [drawable respondsToSelector:@selector(presentAfterMinimumDuration:)];
-                
-        if (hasPresentAfterMinimumDuration && syncInterval > 0.0f)
+        NativeScreenType* nativeScreen = [NativeScreenType mainScreen];
+        return [nativeScreen maximumFramesPerSecond];
+    }
+
+    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval, float refreshRate)
+    {
+        //seconds per frame (1/refreshrate) * num frames (sync interval)
+        float presentAfterMinimumDuration = syncInterval / refreshRate;
+        if (hasPresentAfterMinimumDuration > 0.0f)
         {
-            [mtlCommandBuffer presentDrawable:drawable afterMinimumDuration:syncInterval];
+            [mtlCommandBuffer presentDrawable:drawable afterMinimumDuration:presentAfterMinimumDuration];
         }
         else
         {

Gems/Atom/RHI/Metal/Code/Source/RHI/SwapChain.cpp

@@ -19,8 +19,9 @@ namespace Platform
     CGFloat GetScreenScale();
     void AttachViewController(NativeWindowType* nativeWindow, NativeViewControllerType* viewController, RHIMetalView* metalView);
     void UnAttachViewController(NativeWindowType* nativeWindow, NativeViewControllerType* viewController);
-    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval);
+    void PresentInternal(id <MTLCommandBuffer> mtlCommandBuffer, id<CAMetalDrawable> drawable, float syncInterval, float refreshRate);
     void ResizeInternal(RHIMetalView* metalView, CGSize viewSize);
+    float GetRefreshRate();
     RHIMetalView* GetMetalView(NativeWindowType* nativeWindow);
 }
 
@@ -73,6 +74,15 @@ namespace AZ
                 AddSubView();
             }
 
+            m_refreshRate = Platform::GetRefreshRate();
+            
+            //Assume 60hz if 0 is returned.
+            //Internal OSX displays have 'flexible' refresh rates, with a max of 60Hz - but report 0hz
+            if (m_refreshRate < 0.1f)
+            {
+                m_refreshRate = 60.0f;
+            }
+            
             m_drawables.resize(descriptor.m_dimensions.m_imageCount);
 
             if (nativeDimensions)
@@ -148,10 +158,9 @@ namespace AZ
         uint32_t SwapChain::PresentInternal()
         {
             const uint32_t currentImageIndex = GetCurrentImageIndex();
-            //GFX TODO][ATOM-432] - Hardcoding to 30fps for now. Only used by ios. This needs to be driven by higher level code.
-            float syncInterval = 1.0f/30.0f;
+            
             //Preset the drawable
-            Platform::PresentInternal(m_mtlCommandBuffer, m_drawables[currentImageIndex], syncInterval);
+            Platform::PresentInternal(m_mtlCommandBuffer, m_drawables[currentImageIndex], GetDescriptor().m_verticalSyncInterval, m_refreshRate);
             
             [m_drawables[currentImageIndex] release];
             m_drawables[currentImageIndex] = nil;

Gems/Atom/RHI/Metal/Code/Source/RHI/SwapChain.h

@@ -52,6 +52,7 @@ namespace AZ
             id<MTLDevice> m_mtlDevice = nil;
             NativeWindowType* m_nativeWindow = nullptr;
             AZStd::vector<id<CAMetalDrawable>> m_drawables;
+            float m_refreshRate = 0.0f;
         };
     }
 }

Gems/Atom/RPI/Code/Source/RPI.Public/Shader/ShaderResourceGroupPool.cpp

@@ -58,8 +58,8 @@ namespace AZ
             RHI::ShaderResourceGroupPoolDescriptor poolDescriptor;
             poolDescriptor.m_layout = shaderAsset.FindShaderResourceGroupLayout(srgName, supervariantIndex).get();
 
-            
-            m_pool->SetName(srgName);
+            m_pool->SetName(AZ::Name(AZStd::string::format("%s_%s",shaderAsset.GetName().GetCStr(),srgName.GetCStr())));
+ 
             const RHI::ResultCode resultCode = m_pool->Init(*device, poolDescriptor);
             return resultCode;
         }

Gems/Atom/RPI/Code/Source/RPI.Public/WindowContext.cpp

@@ -27,7 +27,7 @@ void OnVsyncIntervalChanged(uint32_t const& interval)
 // NOTE: On change, broadcasts the new requested vsync interval to all windows.
 // The value of the vsync interval is constrained between 0 and 4
 // Vsync intervals greater than 1 are not currently supported on the Vulkan RHI (see #2061 for discussion)
-AZ_CVAR(uint32_t, rpi_vsync_interval, 0, OnVsyncIntervalChanged, AZ::ConsoleFunctorFlags::Null, "Set swapchain vsync interval");
+AZ_CVAR(uint32_t, rpi_vsync_interval, 1, OnVsyncIntervalChanged, AZ::ConsoleFunctorFlags::Null, "Set swapchain vsync interval");
 
 namespace AZ
 {