Add support for finding/creating general GrVkRenderPass from the VkResourceProvider.

src/gpu/vk/GrVkRenderPass.h

Index: src/gpu/vk/GrVkRenderPass.h
diff --git a/src/gpu/vk/GrVkRenderPass.h b/src/gpu/vk/GrVkRenderPass.h
index 082cccda776223d6240ef24b47a6be56b0579062..054f08e6a5ff766e1a6f8e8b19467fa72e975537 100644
--- a/src/gpu/vk/GrVkRenderPass.h
+++ b/src/gpu/vk/GrVkRenderPass.h
@@ -21,25 +21,56 @@ class GrVkRenderTarget;
 class GrVkRenderPass : public GrVkResource {
 public:
     GrVkRenderPass() : INHERITED(), fRenderPass(VK_NULL_HANDLE) {}
+
+    struct LoadStoreOps {
+        VkAttachmentLoadOp  fLoadOp;
+        VkAttachmentStoreOp fStoreOp;
+
+        LoadStoreOps()
+            : fLoadOp(VK_ATTACHMENT_LOAD_OP_LOAD)

[jvanverth1, 2016/06/02 21:26:48]

This means any time you create any of these structs without the explicit
initializer, it'll call this, whether you want it or not (e.g., you might
overwrite it with other data immediately). In the constructor for AttachmentDesc
you could use the explicit fLoadStoreOps(VK_ATTACHMENT_LOAD_OP_LOAD,
VK_ATTACHMENT_STORE_OP_STORE) instead.

[egdaniel, 2016/06/06 14:14:58]

Done.

+            , fStoreOp(VK_ATTACHMENT_STORE_OP_STORE) {}
+
+        LoadStoreOps(VkAttachmentLoadOp loadOp, VkAttachmentStoreOp storeOp)
+            : fLoadOp(loadOp),
+            fStoreOp(storeOp) {}
+
+        bool operator==(const LoadStoreOps& right) const {
+            return fLoadOp == right.fLoadOp && fStoreOp == right.fStoreOp;
+        }
+
+        bool operator!=(const LoadStoreOps& right) const {
+            return !(*this == right);
+        }
+    };
+    static const LoadStoreOps kBasicLoadStoreOps;
+
     void initSimple(const GrVkGpu* gpu, const GrVkRenderTarget& target);
+    void init(const GrVkGpu* gpu,
+              const GrVkRenderTarget& target,
+              const LoadStoreOps& colorOp,
+              const LoadStoreOps& resolveOp,
+              const LoadStoreOps& stencilOp);
+
+    void init(const GrVkGpu* gpu,
+              const GrVkRenderPass& compatibleRenderPass,
+              const LoadStoreOps& colorOp,
+              const LoadStoreOps& resolveOp,
+              const LoadStoreOps& stencilOp);
 
     struct AttachmentsDescriptor {
         struct AttachmentDesc {
             VkFormat fFormat;
             int fSamples;
-            VkAttachmentLoadOp fLoadOp;
-            VkAttachmentStoreOp fStoreOp;
+            LoadStoreOps fLoadStoreOps;
 
             AttachmentDesc()
                 : fFormat(VK_FORMAT_UNDEFINED)
                 , fSamples(0)
-                , fLoadOp(VK_ATTACHMENT_LOAD_OP_LOAD)
-                , fStoreOp(VK_ATTACHMENT_STORE_OP_STORE) {}
+                , fLoadStoreOps() {}
             bool operator==(const AttachmentDesc& right) const {
                 return (fFormat == right.fFormat &&
                         fSamples == right.fSamples &&
-                        fLoadOp == right.fLoadOp &&
-                        fStoreOp == right.fStoreOp);
+                        fLoadStoreOps == right.fLoadStoreOps);
             }
             bool operator!=(const AttachmentDesc& right) const {
                 return !(*this == right);
@@ -84,6 +115,10 @@ public:
     // basic RenderPasses that can be used when creating a VkFrameBuffer object.
     bool isCompatible(const GrVkRenderTarget& target) const;
 
+    bool equalLoadStoreOps(const LoadStoreOps& colorOps,
+                           const LoadStoreOps& resolveOps,
+                           const LoadStoreOps& stencilOps) const;
+
     VkRenderPass vkRenderPass() const { return fRenderPass; }
 
     void genKey(GrProcessorKeyBuilder* b) const;
@@ -91,6 +126,11 @@ public:
 private:
     GrVkRenderPass(const GrVkRenderPass&);
 
+    void init(const GrVkGpu* gpu,
+              const LoadStoreOps& colorOps,
+              const LoadStoreOps& resolveOps,
+              const LoadStoreOps& stencilOps);
+
     void freeGPUData(const GrVkGpu* gpu) const override;
 
     VkRenderPass          fRenderPass;