Consolidate GPU buffer implementations

Consolidates all the different buffer implementations into a single
GrBuffer class. This will allow us to add new buffer types, use DSA in
OpenGL, track buffer bindings by unique ID, cache buffers without
respect to the type of data they have been used for previously, etc.
This change is strictly a refactor; it introduces no change in
functionality.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search2?unt=true&query=source_type%3Dgm&master=false&issue=1825393002

Review URL: https://codereview.chromium.org/1825393002

3 files changed, 29 insertions, 13 deletions

diff --git a/include/gpu/GrCaps.h b/include/gpu/GrCaps.h
index 1f5b11955b..3ef8295e2b 100644
--- a/include/gpu/GrCaps.h
+++ b/include/gpu/GrCaps.h
@@ -247,9 +247,9 @@ public:
         return fDrawPathMasksToCompressedTextureSupport;
     }
 
-    size_t geometryBufferMapThreshold() const {
-        SkASSERT(fGeometryBufferMapThreshold >= 0);
-        return fGeometryBufferMapThreshold;
+    size_t bufferMapThreshold() const {
+        SkASSERT(fBufferMapThreshold >= 0);
+        return fBufferMapThreshold;
     }
 
     bool supportsInstancedDraws() const {
@@ -301,7 +301,7 @@ protected:
     GR_STATIC_ASSERT(kLast_GrBlendEquation < 32);
 
     uint32_t fMapBufferFlags;
-    int fGeometryBufferMapThreshold;
+    int fBufferMapThreshold;
 
     int fMaxRenderTargetSize;
     int fMaxVertexAttributes;
diff --git a/include/gpu/GrContextOptions.h b/include/gpu/GrContextOptions.h
index d7070db555..4e763405e1 100644
--- a/include/gpu/GrContextOptions.h
+++ b/include/gpu/GrContextOptions.h
@@ -17,7 +17,7 @@ struct GrContextOptions {
         , fMaxTextureSizeOverride(SK_MaxS32)
         , fMaxTileSizeOverride(0)
         , fSuppressDualSourceBlending(false)
-        , fGeometryBufferMapThreshold(-1)
+        , fBufferMapThreshold(-1)
         , fUseDrawInsteadOfPartialRenderTargetWrite(false)
         , fImmediateMode(false)
         , fClipBatchToBounds(false)
@@ -47,7 +47,7 @@ struct GrContextOptions {
     /** the threshold in bytes above which we will use a buffer mapping API to map vertex and index
         buffers to CPU memory in order to update them.  A value of -1 means the GrContext should
         deduce the optimal value for this platform. */
-    int  fGeometryBufferMapThreshold;
+    int  fBufferMapThreshold;
 
     /** some gpus have problems with partial writes of the rendertarget */
     bool fUseDrawInsteadOfPartialRenderTargetWrite;
diff --git a/include/gpu/GrTypesPriv.h b/include/gpu/GrTypesPriv.h
index a2facfa6cf..bf8ea49063 100644
--- a/include/gpu/GrTypesPriv.h
+++ b/include/gpu/GrTypesPriv.h
@@ -401,13 +401,29 @@ private:
 };
 
 /**
- * Indicates the transfer direction for a transfer buffer
- */
-enum TransferType {
-    /** Caller intends to use the buffer to transfer data to the GPU */
-    kCpuToGpu_TransferType,
-    /** Caller intends to use the buffer to transfer data from the GPU */
-    kGpuToCpu_TransferType
+* Indicates the type of data that a GPU buffer will be used for.
+*/
+enum GrBufferType {
+    kVertex_GrBufferType,
+    kIndex_GrBufferType,
+    kXferCpuToGpu_GrBufferType,
+    kXferGpuToCpu_GrBufferType,
+
+    kLast_GrBufferType = kXferGpuToCpu_GrBufferType
+};
+
+/**
+* Provides a performance hint regarding the frequency at which a data store will be accessed.
+*/
+enum GrAccessPattern {
+    /** Data store will be respecified repeatedly and used many times. */
+    kDynamic_GrAccessPattern,
+    /** Data store will be specified once and used many times. (Thus disqualified from caching.) */
+    kStatic_GrAccessPattern,
+    /** Data store will be specified once and used at most a few times. (Also can't be cached.) */
+    kStream_GrAccessPattern,
+
+    kLast_GrAccessPattern = kStream_GrAccessPattern
 };