[dxvk] Implement bindRenderTargets method

An alternative to manually creating a framebuffer object and binding
it via bindFramebuffer. Future optmizations can use this to bring
down the number of redundant render pass changes.

src/d3d11/d3d11_context.cpp

@@ -2458,11 +2458,8 @@ namespace dxvk {
     }
     
     // Create and bind the framebuffer object to the context
-    EmitCs([attachments, dev = m_device] (DxvkContext* ctx) {
-      Rc<DxvkFramebuffer> framebuffer = nullptr;
-      if (attachments.hasAttachments())
-        framebuffer = dev->createFramebuffer(attachments);
-      ctx->bindFramebuffer(framebuffer);
+    EmitCs([cAttachments = std::move(attachments)] (DxvkContext* ctx) {
+      ctx->bindRenderTargets(cAttachments);
     });
   }
   

src/dxvk/dxvk_context.cpp

@@ -93,6 +93,39 @@ namespace dxvk {
       if (fb != nullptr) {
         m_state.gp.state.msSampleCount = fb->sampleCount();
         m_state.gp.state.omRenderPass  = fb->renderPass();
+        
+        m_flags.set(DxvkContextFlag::GpDirtyPipelineState);
+      }
+    }
+  }
+  
+  
+  void DxvkContext::bindRenderTargets(const DxvkRenderTargets& targets) {
+    bool needsUpdate = false;
+    
+    if (m_state.om.framebuffer != nullptr) {
+      const DxvkRenderTargets& active = m_state.om.framebuffer->renderTargets();
+      
+      needsUpdate |= active.getDepthTarget().view   != targets.getDepthTarget().view
+                  || active.getDepthTarget().layout != targets.getDepthTarget().layout;
+      
+      for (uint32_t i = 0; i < MaxNumRenderTargets && !needsUpdate; i++) {
+        needsUpdate |= active.getColorTarget(i).view   != targets.getColorTarget(i).view
+                    || active.getColorTarget(i).layout != targets.getColorTarget(i).layout;
+      }
+    } else {
+      needsUpdate = targets.hasAttachments();
+    }
+    
+    if (needsUpdate) {
+      Rc<DxvkFramebuffer> fb = targets.hasAttachments()
+        ? m_device->createFramebuffer(targets)
+        : nullptr;
+      
+      if (fb != nullptr) {
+        m_state.gp.state.msSampleCount = fb->sampleCount();
+        m_state.gp.state.omRenderPass  = fb->renderPass();
+        
         m_flags.set(DxvkContextFlag::GpDirtyPipelineState);
       }
     }

src/dxvk/dxvk_context.h

@@ -78,6 +78,17 @@ namespace dxvk {
     void bindFramebuffer(
       const Rc<DxvkFramebuffer>& fb);
     
+    /**
+     * \brief Sets render targets
+     * 
+     * Creates a framebuffer on the fly if necessary
+     * and binds it using \c bindFramebuffer. Prefer
+     * this method over doing the same thing manually.
+     * \param [in] targets Render targets to bind
+     */
+    void bindRenderTargets(
+      const DxvkRenderTargets&    targets);
+    
     /**
      * \brief Binds index buffer
      *