Create GrDraw and start fast pathing src over rects

src/gpu/batches/GrBatch.h

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef GrBatch_DEFINED
 #define GrBatch_DEFINED
 
 #include <new>
 #include "GrNonAtomicRef.h"
 
 #include "SkRect.h"
 #include "SkString.h"
 
+#include "draws/GrDraw.h"
+
 class GrCaps;
 class GrBatchFlushState;
 
 /**
  * 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
  * subclasses complete freedom to decide how / what they can batch.
  *
  * Batches are created when GrContext processes a draw call. Batches of the same  subclass may be
@@ skipping 75 matching lines @@
     /** Issues the batches commands to GrGpu. */
     void draw(GrBatchFlushState* state) { this->onDraw(state); }
 
     /** Used to block batching across render target changes. Remove this once we store
         GrBatches for different RTs in different targets. */
     virtual uint32_t renderTargetUniqueID() const = 0;
 
     /** Used for spewing information about batches when debugging. */
     virtual SkString dumpInfo() const = 0;
 
+    // TODO put on stack
+    template <class T> T* getSnapStorage() {

[bsalomon, 2015/09/23 13:49:38]

Can we do anything here with var args to forward constructor args a la
SkTLazy::init?

[joshualitt, 2015/09/25 18:17:12]

Acknowledged.

+        SkASSERT(sizeof(T) < fSnapStorage.size());
+        fSnap = reinterpret_cast<GrDrawSnap*>(fSnapStorage.get());
+        return reinterpret_cast<T*>(fSnap);
+    }
+    const GrDrawSnap* drawSnap() const { return fSnap; }
+
 protected:
     // NOTE, compute some bounds, even if extremely conservative.  Do *NOT* setLargest on the bounds
     // rect because we outset it for dst copy textures
     void setBounds(const SkRect& newBounds) { fBounds = newBounds; }
 
     void joinBounds(const SkRect& otherBounds) {
         return fBounds.joinPossiblyEmptyRect(otherBounds);
     }
 
     static uint32_t GenBatchClassID() { return GenID(&gCurrBatchClassID); }
@@ skipping 21 matching lines @@
         kIllegalBatchID = 0,
     };
 
     SkDEBUGCODE(bool                    fUsed;)
     const uint32_t                      fClassID;
 #if GR_BATCH_SPEW
     static uint32_t GenBatchID() { return GenID(&gCurrBatchUniqueID); }
     const uint32_t                      fUniqueID;
     static int32_t                      gCurrBatchUniqueID;
 #endif
+    GrDrawSnap*                        fSnap;

[bsalomon, 2015/09/23 13:49:38]

alignment

[robertphillips, 2015/09/25 12:48:48]

How was 256 arrived at ?

[joshualitt, 2015/09/25 18:17:12]

magic!  I'll add a comment

[joshualitt, 2015/09/25 18:17:12]

Acknowledged.

+    SkAlignedSStorage<256>             fSnapStorage;
+
     static int32_t                      gCurrBatchClassID;
     typedef GrNonAtomicRef INHERITED;
 };
 
 #endif