1 files changed, 66 insertions, 13 deletions

diff --git a/intern/ghost/intern/GHOST_ContextCGL.h b/intern/ghost/intern/GHOST_ContextCGL.h
index badc3241107..130b926f25c 100644
--- a/intern/ghost/intern/GHOST_ContextCGL.h
+++ b/intern/ghost/intern/GHOST_ContextCGL.h
@@ -9,8 +9,13 @@
 
 #include "GHOST_Context.h"
 
+#include <Cocoa/Cocoa.h>
+#include <Metal/Metal.h>
+#include <QuartzCore/QuartzCore.h>
+
 @class CAMetalLayer;
 @class MTLCommandQueue;
+@class MTLDevice;
 @class MTLRenderPipelineState;
 @class MTLTexture;
 @class NSOpenGLContext;
@@ -36,62 +41,89 @@ class GHOST_ContextCGL : public GHOST_Context {
    * Swaps front and back buffers of a window.
    * \return A boolean success indicator.
    */
-  GHOST_TSuccess swapBuffers();
+  GHOST_TSuccess swapBuffers() override;
 
   /**
    * Activates the drawing context of this window.
    * \return A boolean success indicator.
    */
-  GHOST_TSuccess activateDrawingContext();
+  GHOST_TSuccess activateDrawingContext() override;
 
   /**
    * Release the drawing context of the calling thread.
    * \return A boolean success indicator.
    */
-  GHOST_TSuccess releaseDrawingContext();
+  GHOST_TSuccess releaseDrawingContext() override;
 
-  unsigned int getDefaultFramebuffer();
+  unsigned int getDefaultFramebuffer() override;
 
   /**
    * Call immediately after new to initialize.  If this fails then immediately delete the object.
    * \return Indication as to whether initialization has succeeded.
    */
-  GHOST_TSuccess initializeDrawingContext();
+  GHOST_TSuccess initializeDrawingContext() override;
 
   /**
    * Removes references to native handles from this context and then returns
    * \return GHOST_kSuccess if it is OK for the parent to release the handles and
    * GHOST_kFailure if releasing the handles will interfere with sharing
    */
-  GHOST_TSuccess releaseNativeHandles();
+  GHOST_TSuccess releaseNativeHandles() override;
 
   /**
    * Sets the swap interval for #swapBuffers.
    * \param interval: The swap interval to use.
    * \return A boolean success indicator.
    */
-  GHOST_TSuccess setSwapInterval(int interval);
+  GHOST_TSuccess setSwapInterval(int interval) override;
 
   /**
    * Gets the current swap interval for #swapBuffers.
    * \param intervalOut: Variable to store the swap interval if it can be read.
    * \return Whether the swap interval can be read.
    */
-  GHOST_TSuccess getSwapInterval(int &);
+  GHOST_TSuccess getSwapInterval(int &) override;
 
   /**
    * Updates the drawing context of this window.
    * Needed whenever the window is changed.
    * \return Indication of success.
    */
-  GHOST_TSuccess updateDrawingContext();
+  GHOST_TSuccess updateDrawingContext() override;
+
+  /**
+   * Returns a texture that Metal code can use as a render target. The current
+   * contents of this texture will be composited on top of the frame-buffer
+   * each time `swapBuffers` is called.
+   */
+  id<MTLTexture> metalOverlayTexture();
+
+  /**
+   * Return a pointer to the Metal command queue used by this context.
+   */
+  MTLCommandQueue *metalCommandQueue();
+
+  /**
+   * Return a pointer to the Metal device associated with this context.
+   */
+  MTLDevice *metalDevice();
+
+  /**
+   * Register present callback
+   */
+  void metalRegisterPresentCallback(void (*callback)(
+      MTLRenderPassDescriptor *, id<MTLRenderPipelineState>, id<MTLTexture>, id<CAMetalDrawable>));
 
  private:
   /** Metal state */
+  /* Set this flag to `true` when rendering with Metal API for Viewport.
+   * TODO(Metal): This should be assigned to externally. */
+  bool m_useMetalForRendering = false;
   NSView *m_metalView;
   CAMetalLayer *m_metalLayer;
   MTLCommandQueue *m_metalCmdQueue;
   MTLRenderPipelineState *m_metalRenderPipeline;
+  bool m_ownsMetalDevice;
 
   /** OpenGL state, for GPUs that don't support Metal */
   NSOpenGLView *m_openGLView;
@@ -103,10 +135,30 @@ class GHOST_ContextCGL : public GHOST_Context {
   unsigned int m_defaultFramebuffer;
 
   /** The virtualized default frame-buffer's texture. */
-  MTLTexture *m_defaultFramebufferMetalTexture;
-
-  bool m_coreProfile;
-
+  /**
+   * Texture that you can render into with Metal. The texture will be
+   * composited on top of `m_defaultFramebufferMetalTexture` whenever
+   * `swapBuffers` is called.
+   */
+  static const int METAL_SWAPCHAIN_SIZE = 3;
+  struct MTLSwapchainTexture {
+    id<MTLTexture> texture;
+    unsigned int index;
+  };
+  MTLSwapchainTexture m_defaultFramebufferMetalTexture[METAL_SWAPCHAIN_SIZE];
+  unsigned int current_swapchain_index = 0;
+
+  /* Present callback.
+   * We use this such that presentation can be controlled from within the Metal
+   * Context. This is required for optimal performance and clean control flow.
+   * Also helps ensure flickering does not occur by present being dependent
+   * on existing submissions. */
+  void (*contextPresentCallback)(MTLRenderPassDescriptor *,
+                                 id<MTLRenderPipelineState>,
+                                 id<MTLTexture>,
+                                 id<CAMetalDrawable>);
+
+  int mtl_SwapInterval;
   const bool m_debug;
 
   /** The first created OpenGL context (for sharing display lists) */
@@ -119,4 +171,5 @@ class GHOST_ContextCGL : public GHOST_Context {
   void metalInitFramebuffer();
   void metalUpdateFramebuffer();
   void metalSwapBuffers();
+  void initClear();
 };