Add MultiPictureDraw to nanobench

bench/SKPBench.cpp

Index: bench/SKPBench.cpp
diff --git a/bench/SKPBench.cpp b/bench/SKPBench.cpp
index 5844d8a588ab4597ab76661f684ace36865cc9c2..fd8df429c2ad7ccb088f48e7c570a05628118039 100644
--- a/bench/SKPBench.cpp
+++ b/bench/SKPBench.cpp
@@ -7,15 +7,28 @@
 
 #include "SKPBench.h"
 #include "SkCommandLineFlags.h"
+#include "SkMultiPictureDraw.h"
+#include "SkSurface.h"
 
 DEFINE_int32(benchTile, 256, "Tile dimension used for SKP playback.");
 
-SKPBench::SKPBench(const char* name, const SkPicture* pic, const SkIRect& clip, SkScalar scale)
+SKPBench::SKPBench(const char* name, const SkPicture* pic, const SkIRect& clip, SkScalar scale,
+                   bool useMultiPictureDraw)
     : fPic(SkRef(pic))
     , fClip(clip)
     , fScale(scale)
-    , fName(name) {
+    , fName(name)
+    , fUseMultiPictureDraw(useMultiPictureDraw) {
     fUniqueName.printf("%s_%.2g", name, scale);  // Scale makes this unqiue for skiaperf.com traces.
+    if (useMultiPictureDraw) {
+        fUniqueName.append("_mpd");
+    }
+}
+
+SKPBench::~SKPBench() {
+    for (int i = 0; i < fSurfaces.count(); ++i) {
+        fSurfaces[i]->unref();
+    }
 }
 
 const char* SKPBench::onGetName() {
@@ -26,6 +39,49 @@ const char* SKPBench::onGetUniqueName() {
     return fUniqueName.c_str();
 }
 
+void SKPBench::onPerCanvasPreDraw(SkCanvas* canvas) {
+    if (!fUseMultiPictureDraw) {
+        return;
+    }
+
+    SkIRect bounds;
+    SkAssertResult(canvas->getClipDeviceBounds(&bounds));
+
+    int xTiles = SkScalarCeilToInt(bounds.width()  / SkIntToScalar(FLAGS_benchTile));
+    int yTiles = SkScalarCeilToInt(bounds.height() / SkIntToScalar(FLAGS_benchTile));
+
+    fSurfaces.setReserve(xTiles * yTiles);
+    fTileRects.setReserve(xTiles * yTiles);
+
+    SkImageInfo ii = canvas->imageInfo().makeWH(FLAGS_benchTile, FLAGS_benchTile);
+
+    for (int y = bounds.fTop; y < bounds.fBottom; y += FLAGS_benchTile) {
+        for (int x = bounds.fLeft; x < bounds.fRight; x += FLAGS_benchTile) {
+            *fTileRects.append() = SkIRect::MakeXYWH(x, y, FLAGS_benchTile, FLAGS_benchTile);
+            *fSurfaces.push() = canvas->newSurface(ii);
+            fSurfaces.top()->getCanvas()->setMatrix(canvas->getTotalMatrix());
+            fSurfaces.top()->getCanvas()->scale(fScale, fScale);
+        }
+    }
+}
+
+void SKPBench::onPerCanvasPostDraw(SkCanvas* canvas) {
+    if (!fUseMultiPictureDraw) {
+        return;
+    }
+
+    // Draw the last set of tiles into the master canvas in case we're
+    // saving the images
+    for (int i = 0; i < fTileRects.count(); ++i) {
+        canvas->drawImage(fSurfaces[i]->newImageSnapshot(),
+                          SkIntToScalar(fTileRects[i].fLeft), SkIntToScalar(fTileRects[i].fTop));
+        SkSafeSetNull(fSurfaces[i]);
+    }
+
+    fSurfaces.rewind();
+    fTileRects.rewind();
+}
+
 bool SKPBench::isSuitableFor(Backend backend) {
     return backend != kNonRendering_Backend;
 }
@@ -35,21 +91,41 @@ SkIPoint SKPBench::onGetSize() {
 }
 
 void SKPBench::onDraw(const int loops, SkCanvas* canvas) {
-    SkIRect bounds;
-    SkAssertResult(canvas->getClipDeviceBounds(&bounds));
+    if (fUseMultiPictureDraw) {
+        for (int i = 0; i < loops; i++) {
+            SkMultiPictureDraw mpd;
 
-    SkAutoCanvasRestore overall(canvas, true/*save now*/);
-    canvas->scale(fScale, fScale);
+            for (int i = 0; i < fTileRects.count(); ++i) {
+                SkMatrix trans;
+                trans.setTranslate(-fTileRects[i].fLeft/fScale,
+                                   -fTileRects[i].fTop/fScale);
+                mpd.add(fSurfaces[i]->getCanvas(), fPic, &trans);
+            }
+
+            mpd.draw();
 
-    for (int i = 0; i < loops; i++) {
-        for (int y = bounds.fTop; y < bounds.fBottom; y += FLAGS_benchTile) {
-            for (int x = bounds.fLeft; x < bounds.fRight; x += FLAGS_benchTile) {
-                SkAutoCanvasRestore perTile(canvas, true/*save now*/);
-                canvas->clipRect(SkRect::Make(
-                            SkIRect::MakeXYWH(x, y, FLAGS_benchTile, FLAGS_benchTile)));
-                fPic->playback(canvas);
+            for (int i = 0; i < fTileRects.count(); ++i) {
+                fSurfaces[i]->getCanvas()->flush();
             }
         }
-        canvas->flush();
+    } else {
+        SkIRect bounds;
+        SkAssertResult(canvas->getClipDeviceBounds(&bounds));
+
+        SkAutoCanvasRestore overall(canvas, true/*save now*/);
+        canvas->scale(fScale, fScale);
+
+        for (int i = 0; i < loops; i++) {
+            for (int y = bounds.fTop; y < bounds.fBottom; y += FLAGS_benchTile) {
+                for (int x = bounds.fLeft; x < bounds.fRight; x += FLAGS_benchTile) {
+                    SkAutoCanvasRestore perTile(canvas, true/*save now*/);
+                    canvas->clipRect(SkRect::Make(
+                                SkIRect::MakeXYWH(x, y, FLAGS_benchTile, FLAGS_benchTile)));
+                    fPic->playback(canvas);
+                }
+            }
+
+            canvas->flush();
+        }
     }
 }