Introduce GrBatch subclasses GrDrawBatch and GrVertexBatch to prepare for non-drawing batches

src/gpu/batches/GrBatch.h

Index: src/gpu/batches/GrBatch.h
diff --git a/src/gpu/batches/GrBatch.h b/src/gpu/batches/GrBatch.h
index 35844cd99a533d6e6a4e5ab56dd93ac0948d23f0..ef8f56c4b9daa1a5241abbd91947878c437ac59b 100644
--- a/src/gpu/batches/GrBatch.h
+++ b/src/gpu/batches/GrBatch.h
@@ -21,7 +21,7 @@ class GrPipeline;
 
 struct GrInitInvariantOutput;
 
-/*
+/**
  * GrBatch is the base class for all Ganesh deferred geometry generators.  To facilitate
  * reorderable batching, Ganesh does not generate geometry inline with draw calls.  Instead, it
  * captures the arguments to the draw and then generates the geometry on demand.  This gives GrBatch
@@ -51,8 +51,6 @@ public:
     ~GrBatch() override;
 
     virtual const char* name() const = 0;
-    virtual void getInvariantOutputColor(GrInitInvariantOutput* out) const = 0;
-    virtual void getInvariantOutputCoverage(GrInitInvariantOutput* out) const = 0;
 
     bool combineIfPossible(GrBatch* that, const GrCaps& caps) {
         if (this->classID() != that->classID()) {
@@ -62,14 +60,8 @@ public:
         return this->onCombineIfPossible(that, caps);
     }
 
-    virtual void generateGeometry(GrBatchTarget*) = 0;
-
     const SkRect& bounds() const { return fBounds; }
 
-    // TODO this goes away when batches are everywhere
-    void setNumberOfDraws(int numberOfDraws) { fNumberOfDraws = numberOfDraws; }
-    int numberOfDraws() const { return fNumberOfDraws; }
-
     void* operator new(size_t size);
     void operator delete(void* target);
 
@@ -81,28 +73,17 @@ public:
     }
 
     /**
-      * Helper for down-casting to a GrBatch subclass
-      */
+     * Helper for down-casting to a GrBatch subclass
+     */
     template <typename T> const T& cast() const { return *static_cast<const T*>(this); }
     template <typename T> T* cast() { return static_cast<T*>(this); }
 
     uint32_t classID() const { SkASSERT(kIllegalBatchID != fClassID); return fClassID; }
 
-    // TODO no GrPrimitiveProcessors yet read fragment position
-    bool willReadFragmentPosition() const { return false; }
-
-    SkDEBUGCODE(bool isUsed() const { return fUsed; })
-
-    const GrPipeline* pipeline() const {
-        SkASSERT(fPipelineInstalled);
-        return reinterpret_cast<const GrPipeline*>(fPipelineStorage.get());
-    }
-
-    bool installPipeline(const GrPipeline::CreateArgs&);
-
 #if GR_BATCH_SPEW
     uint32_t uniqueID() const { return fUniqueID; }
 #endif
+    SkDEBUGCODE(bool isUsed() const { return fUsed; })
 
 protected:
     template <typename PROC_SUBCLASS> void initClassID() {
@@ -118,8 +99,86 @@ protected:
         return fBounds.joinPossiblyEmptyRect(otherBounds);
     }
 
+    SkRect                              fBounds;
+
+private:
+    virtual bool onCombineIfPossible(GrBatch*, const GrCaps& caps) = 0;
+
+    static uint32_t GenID(int32_t* idCounter) {
+        // fCurrProcessorClassID has been initialized to kIllegalProcessorClassID. The
+        // atomic inc returns the old value not the incremented value. So we add
+        // 1 to the returned value.
+        uint32_t id = static_cast<uint32_t>(sk_atomic_inc(idCounter)) + 1;
+        if (!id) {
+            SkFAIL("This should never wrap as it should only be called once for each GrBatch "
+                   "subclass.");
+        }
+        return id;
+    }
+
+    enum {
+        kIllegalBatchID = 0,
+    };
+
+    uint32_t                            fClassID;
+    SkDEBUGCODE(bool                    fUsed;)
+#if GR_BATCH_SPEW
+    uint32_t                            fUniqueID;
+    static int32_t gCurrBatchUniqueID;
+#endif
+    static int32_t gCurrBatchClassID;
+    typedef GrNonAtomicRef INHERITED;
+};
+
+/**
+ * Base class for GrBatches that draw. These batches have a GrPipeline installed by GrDrawTarget.
+ */
+class GrDrawBatch : public GrBatch {
+public:
+    GrDrawBatch();
+    ~GrDrawBatch() override;
+
+    virtual void getInvariantOutputColor(GrInitInvariantOutput* out) const = 0;
+    virtual void getInvariantOutputCoverage(GrInitInvariantOutput* out) const = 0;
+
+    const GrPipeline* pipeline() const {
+        SkASSERT(fPipelineInstalled);
+        return reinterpret_cast<const GrPipeline*>(fPipelineStorage.get());
+    }
+
+    bool installPipeline(const GrPipeline::CreateArgs&);
+
+    // TODO no GrPrimitiveProcessors yet read fragment position
+    bool willReadFragmentPosition() const { return false; }
+
+private:
+    /**
+     * initBatchTracker is a hook for the some additional overrides / optimization possibilities
+     * from the GrXferProcessor.
+     */
+    virtual void initBatchTracker(const GrPipelineOptimizations&) = 0;
+
+    SkAlignedSTStorage<1, GrPipeline>   fPipelineStorage;
+    bool                                fPipelineInstalled;
+    typedef GrBatch INHERITED;
+};
+
+/**
+ * Base class for vertex-based GrBatches.
+ */
+class GrVertexBatch : public GrDrawBatch {
+public:
+    GrVertexBatch();
+
+    virtual void generateGeometry(GrBatchTarget*) = 0;
+
+    // TODO this goes away when batches are everywhere
+    void setNumberOfDraws(int numberOfDraws) { fNumberOfDraws = numberOfDraws; }
+    int numberOfDraws() const { return fNumberOfDraws; }
+
+protected:
     /** Helper for rendering instances using an instanced index index buffer. This class creates the
-        space for the vertices and flushes the draws to the batch target.*/
+        space for the vertices and flushes the draws to the batch target. */
    class InstancedHelper {
    public:
         InstancedHelper() {}
@@ -156,44 +215,9 @@ protected:
         typedef InstancedHelper INHERITED;
     };
 
-    uint32_t fClassID;
-    SkRect fBounds;
-
 private:
-    virtual bool onCombineIfPossible(GrBatch*, const GrCaps& caps) = 0;
-
-    /*
-     * initBatchTracker is a hook for the some additional overrides / optimization possibilities
-     * from the GrXferProcessor.
-     */
-    virtual void initBatchTracker(const GrPipelineOptimizations&) = 0;
-
-
-    static uint32_t GenID(int32_t* idCounter) {
-        // fCurrProcessorClassID has been initialized to kIllegalProcessorClassID. The
-        // atomic inc returns the old value not the incremented value. So we add
-        // 1 to the returned value.
-        uint32_t id = static_cast<uint32_t>(sk_atomic_inc(idCounter)) + 1;
-        if (!id) {
-            SkFAIL("This should never wrap as it should only be called once for each GrBatch "
-                   "subclass.");
-        }
-        return id;
-    }
-
-    enum {
-        kIllegalBatchID = 0,
-    };
-    SkAlignedSTStorage<1, GrPipeline>   fPipelineStorage;
     int                                 fNumberOfDraws;
-    SkDEBUGCODE(bool                    fUsed;)
-    bool                                fPipelineInstalled;
-#if GR_BATCH_SPEW
-    uint32_t                            fUniqueID;
-    static int32_t gCurrBatchUniqueID;
-#endif
-    static int32_t gCurrBatchClassID;
-    typedef SkRefCnt INHERITED;
+    typedef GrDrawBatch INHERITED;
 };
 
 #endif