Begin instanced rendering for simple shapes

Adds a module that performs instanced rendering and starts using it
for a select subset of draws on Mac GL platforms. The instance
processor can currently handle rects, ovals, round rects, and double
round rects. It can generalize shapes as round rects in order to
improve batching. The instance processor also employs new drawing
algorithms, irrespective of instanced rendering, that improve GPU-side
performance (e.g. sample mask, different triangle layouts, etc.).

This change only scratches the surface of instanced rendering. The
majority of draws still only have one instance. Future work may
include:

 * Passing coord transforms through the texel buffer.
 * Sending FP uniforms through instanced vertex attribs.
 * Using instanced rendering for more draws (stencil writes,
   drawAtlas, etc.).
 * Adding more shapes to the instance processor’s repertoire.
 * Batching draws that have mismatched scissors (analyzing draw
   bounds, inserting clip planes, etc.).
 * Bindless textures.
 * Uber shaders.

BUG=skia:
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2066993003

Committed: https://skia.googlesource.com/skia/+/42eafa4bc00354b132ad114d22ed6b95d8849891
Review-Url: https://codereview.chromium.org/2066993003

1 files changed, 20 insertions, 13 deletions

diff --git a/src/gpu/GrDrawTarget.h b/src/gpu/GrDrawTarget.h
index 64c8a3345c..2a5bbde1a3 100644
--- a/src/gpu/GrDrawTarget.h
+++ b/src/gpu/GrDrawTarget.h
@@ -144,6 +144,11 @@ public:
                      const SkIRect& srcRect,
                      const SkIPoint& dstPoint);
 
+    /**
+     * Gets the shape rendering object if it is supported on this platform.
+     */
+    gr_instanced::InstancedRendering* instancedRendering() const { return fInstancedRendering; }
+
 private:
     friend class GrDrawingManager; // for resetFlag & TopoSortTraits
     friend class GrDrawContextPriv; // for clearStencilClip
@@ -209,24 +214,26 @@ private:
     // Used only by drawContextPriv.
     void clearStencilClip(const SkIRect&, bool insideClip, GrRenderTarget*);
 
-    SkSTArray<256, SkAutoTUnref<GrBatch>, true> fBatches;
+    SkSTArray<256, SkAutoTUnref<GrBatch>, true>     fBatches;
     // The context is only in service of the clip mask manager, remove once CMM doesn't need this.
-    GrContext*                                  fContext;
-    GrGpu*                                      fGpu;
-    GrResourceProvider*                         fResourceProvider;
-    GrAuditTrail*                               fAuditTrail;
+    GrContext*                                      fContext;
+    GrGpu*                                          fGpu;
+    GrResourceProvider*                             fResourceProvider;
+    GrAuditTrail*                                   fAuditTrail;
 
-    SkDEBUGCODE(int                             fDebugID;)
-    uint32_t                                    fFlags;
+    SkDEBUGCODE(int                                 fDebugID;)
+    uint32_t                                        fFlags;
 
     // 'this' drawTarget relies on the output of the drawTargets in 'fDependencies'
-    SkTDArray<GrDrawTarget*>                    fDependencies;
-    GrRenderTarget*                             fRenderTarget;
+    SkTDArray<GrDrawTarget*>                        fDependencies;
+    GrRenderTarget*                                 fRenderTarget;
+
+    bool                                            fClipBatchToBounds;
+    bool                                            fDrawBatchBounds;
+    int                                             fMaxBatchLookback;
+    int                                             fMaxBatchLookahead;
 
-    bool                                        fClipBatchToBounds;
-    bool                                        fDrawBatchBounds;
-    int                                         fMaxBatchLookback;
-    int                                         fMaxBatchLookahead;
+    SkAutoTDelete<gr_instanced::InstancedRendering> fInstancedRendering;
 
     typedef SkRefCnt INHERITED;
 };