Refactor creation of GrVkRenderPasses to make them move general

src/gpu/vk/GrVkRenderPass.cpp

Index: src/gpu/vk/GrVkRenderPass.cpp
diff --git a/src/gpu/vk/GrVkRenderPass.cpp b/src/gpu/vk/GrVkRenderPass.cpp
index 1aedab4cfa985dd35fcef1d7ec173f9129cd576d..c56bafa92daa367c547d95adbf4b36961255103e 100644
--- a/src/gpu/vk/GrVkRenderPass.cpp
+++ b/src/gpu/vk/GrVkRenderPass.cpp
@@ -13,17 +13,31 @@
 #include "GrVkRenderTarget.h"
 #include "GrVkUtil.h"
 
-void setup_simple_vk_attachment_description(VkAttachmentDescription* attachment,
-                                            VkFormat format,
-                                            uint32_t samples,
-                                            VkImageLayout layout) {
+typedef GrVkRenderPass::AttachmentsDescriptor::AttachmentDesc AttachmentDesc;
+
+void setup_vk_attachment_description(VkAttachmentDescription* attachment,
+                                     const AttachmentDesc& desc,
+                                     VkImageLayout layout) {
     attachment->flags = 0;
-    attachment->format = format;
-    SkAssertResult(GrSampleCountToVkSampleCount(samples, &attachment->samples));
-    attachment->loadOp = VK_ATTACHMENT_LOAD_OP_LOAD;
-    attachment->storeOp = VK_ATTACHMENT_STORE_OP_STORE;
-    attachment->stencilLoadOp = VK_ATTACHMENT_LOAD_OP_LOAD;
-    attachment->stencilStoreOp = VK_ATTACHMENT_STORE_OP_STORE;
+    attachment->format = desc.fFormat;
+    SkAssertResult(GrSampleCountToVkSampleCount(desc.fSamples, &attachment->samples));
+    switch (layout) {
+        case VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL:
+            attachment->loadOp = desc.fLoadOp;
+            attachment->storeOp = desc.fStoreOp;
+            attachment->stencilLoadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
+            attachment->stencilStoreOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
+            break;
+        case VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL:
+            attachment->loadOp = VK_ATTACHMENT_LOAD_OP_DONT_CARE;
+            attachment->storeOp = VK_ATTACHMENT_STORE_OP_DONT_CARE;
+            attachment->stencilLoadOp = desc.fLoadOp;
+            attachment->stencilStoreOp = desc.fStoreOp;
+            break;
+        default:
+            SkFAIL("Unexpected attachment layout");
+    }
+
     attachment->initialLayout = layout;
     attachment->finalLayout = layout;
 }
@@ -56,10 +70,9 @@ void GrVkRenderPass::initSimple(const GrVkGpu* gpu, const GrVkRenderTarget& targ
     subpassDesc.pInputAttachments = nullptr;
     if (fAttachmentFlags & kColor_AttachmentFlag) {
         // set up color attachment
-        setup_simple_vk_attachment_description(&attachments[currentAttachment],
-                                               fAttachmentsDescriptor.fColor.fFormat,
-                                               fAttachmentsDescriptor.fColor.fSamples,
-                                               VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
+        setup_vk_attachment_description(&attachments[currentAttachment],
+                                        fAttachmentsDescriptor.fColor,
+                                        VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
         // setup subpass use of attachment
         colorRef.attachment = currentAttachment++;
         colorRef.layout = VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL;
@@ -75,10 +88,9 @@ void GrVkRenderPass::initSimple(const GrVkGpu* gpu, const GrVkRenderTarget& targ
 
     if (fAttachmentFlags & kResolve_AttachmentFlag) {
         // set up resolve attachment
-        setup_simple_vk_attachment_description(&attachments[currentAttachment],
-                                               fAttachmentsDescriptor.fResolve.fFormat,
-                                               fAttachmentsDescriptor.fResolve.fSamples,
-                                               VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
+        setup_vk_attachment_description(&attachments[currentAttachment],
+                                        fAttachmentsDescriptor.fResolve,
+                                        VK_IMAGE_LAYOUT_COLOR_ATTACHMENT_OPTIMAL);
         // setup subpass use of attachment
         resolveRef.attachment = currentAttachment++;
         // I'm really not sure what the layout should be for the resolve textures.
@@ -90,10 +102,9 @@ void GrVkRenderPass::initSimple(const GrVkGpu* gpu, const GrVkRenderTarget& targ
 
     if (fAttachmentFlags & kStencil_AttachmentFlag) {
         // set up stencil attachment
-        setup_simple_vk_attachment_description(&attachments[currentAttachment],
-                                               fAttachmentsDescriptor.fStencil.fFormat,
-                                               fAttachmentsDescriptor.fStencil.fSamples,
-                                               VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL);
+        setup_vk_attachment_description(&attachments[currentAttachment],
+                                        fAttachmentsDescriptor.fStencil,
+                                        VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL);
         // setup subpass use of attachment
         stencilRef.attachment = currentAttachment++;
         stencilRef.layout = VK_IMAGE_LAYOUT_DEPTH_STENCIL_ATTACHMENT_OPTIMAL;
@@ -202,17 +213,17 @@ bool GrVkRenderPass::isCompatible(const GrVkRenderTarget& target) const {
     }
 
     if (fAttachmentFlags & kColor_AttachmentFlag) {
-        if (fAttachmentsDescriptor.fColor != desc.fColor) {
+        if (!fAttachmentsDescriptor.fColor.isCompatible(desc.fColor)) {
             return false;
         }
     }
     if (fAttachmentFlags & kResolve_AttachmentFlag) {
-        if (fAttachmentsDescriptor.fResolve != desc.fResolve) {
+        if (!fAttachmentsDescriptor.fResolve.isCompatible(desc.fResolve)) {
             return false;
         }
     }
     if (fAttachmentFlags & kStencil_AttachmentFlag) {
-        if (fAttachmentsDescriptor.fStencil != desc.fStencil) {
+        if (!fAttachmentsDescriptor.fStencil.isCompatible(desc.fStencil)) {
             return false;
         }
     }