Fix bug in layer hoisting transition to SkRecord backend

Care must be taken when setting up the initial CTM matrix for partial SkRecord playbacks b.c. all the setMatrix calls will concatenate with the initial matrix (which may be different then the CTM that is required to draw correctly).

R=mtklein@google.com, bsalomon@google.com

Author: robertphillips@google.com

Review URL: https://codereview.chromium.org/549143003

8 files changed, 58 insertions, 26 deletions

diff --git a/src/core/SkRecordDraw.cpp b/src/core/SkRecordDraw.cpp
index e1975e1fe3..8bd12d00c8 100644
--- a/src/core/SkRecordDraw.cpp
+++ b/src/core/SkRecordDraw.cpp
@@ -48,11 +48,12 @@ void SkRecordDraw(const SkRecord& record,
 void SkRecordPartialDraw(const SkRecord& record,
                          SkCanvas* canvas,
                          const SkRect& clearRect,
-                         unsigned start, unsigned stop) {
+                         unsigned start, unsigned stop,
+                         const SkMatrix& initialCTM) {
     SkAutoCanvasRestore saveRestore(canvas, true /*save now, restore at exit*/);
 
     stop = SkTMin(stop, record.count());
-    SkRecords::PartialDraw draw(canvas, clearRect);
+    SkRecords::PartialDraw draw(canvas, clearRect, initialCTM);
     for (unsigned i = start; i < stop; i++) {
         record.visit<void>(i, draw);
     }
diff --git a/src/core/SkRecordDraw.h b/src/core/SkRecordDraw.h
index 033b76d34a..75921d182f 100644
--- a/src/core/SkRecordDraw.h
+++ b/src/core/SkRecordDraw.h
@@ -11,6 +11,7 @@
 #include "SkBBoxHierarchy.h"
 #include "SkCanvas.h"
 #include "SkDrawPictureCallback.h"
+#include "SkMatrix.h"
 #include "SkRecord.h"
 
 // Fill a BBH to be used by SkRecordDraw to accelerate playback.
@@ -20,15 +21,21 @@ void SkRecordFillBounds(const SkRecord&, SkBBoxHierarchy*);
 void SkRecordDraw(const SkRecord&, SkCanvas*, const SkBBoxHierarchy*, SkDrawPictureCallback*);
 
 // Draw a portion of an SkRecord into an SkCanvas while replacing clears with drawRects.
-void SkRecordPartialDraw(const SkRecord&, SkCanvas*, const SkRect&, unsigned start, unsigned stop);
+// When drawing a portion of an SkRecord the CTM on the passed in canvas must be
+// the composition of the replay matrix with the record-time CTM (for the portion
+// of the record that is being replayed). For setMatrix calls to behave correctly
+// the initialCTM parameter must set to just the replay matrix.
+void SkRecordPartialDraw(const SkRecord&, SkCanvas*, const SkRect&, unsigned start, unsigned stop,
+                         const SkMatrix& initialCTM);
 
 namespace SkRecords {
 
 // This is an SkRecord visitor that will draw that SkRecord to an SkCanvas.
 class Draw : SkNoncopyable {
 public:
-    explicit Draw(SkCanvas* canvas)
-        : fInitialCTM(canvas->getTotalMatrix()), fCanvas(canvas) {}
+    explicit Draw(SkCanvas* canvas, const SkMatrix* initialCTM = NULL)
+        : fInitialCTM(initialCTM ? *initialCTM : canvas->getTotalMatrix())
+        , fCanvas(canvas) {}
 
     template <typename T> void operator()(const T& r) {
         this->draw(r);
@@ -45,8 +52,8 @@ private:
 // Used by SkRecordPartialDraw.
 class PartialDraw : public Draw {
 public:
-    PartialDraw(SkCanvas* canvas, const SkRect& clearRect)
-        : INHERITED(canvas), fClearRect(clearRect) {}
+    PartialDraw(SkCanvas* canvas, const SkRect& clearRect, const SkMatrix& initialCTM)
+        : INHERITED(canvas, &initialCTM), fClearRect(clearRect) {}
 
     // Same as Draw for all ops except Clear.
     template <typename T> void operator()(const T& r) {
diff --git a/src/gpu/GrLayerCache.cpp b/src/gpu/GrLayerCache.cpp
index 0c2e6b0a4d..8e61cb761e 100644
--- a/src/gpu/GrLayerCache.cpp
+++ b/src/gpu/GrLayerCache.cpp
@@ -119,28 +119,31 @@ void GrLayerCache::freeAll() {
 
 GrCachedLayer* GrLayerCache::createLayer(uint32_t pictureID, 
                                          int start, int stop, 
+                                         const SkIPoint& offset,
                                          const SkMatrix& ctm) {
     SkASSERT(pictureID != SK_InvalidGenID && start > 0 && stop > 0);
 
-    GrCachedLayer* layer = SkNEW_ARGS(GrCachedLayer, (pictureID, start, stop, ctm));
+    GrCachedLayer* layer = SkNEW_ARGS(GrCachedLayer, (pictureID, start, stop, offset, ctm));
     fLayerHash.add(layer);
     return layer;
 }
 
 GrCachedLayer* GrLayerCache::findLayer(uint32_t pictureID,
                                        int start, int stop, 
+                                       const SkIPoint& offset,
                                        const SkMatrix& ctm) {
     SkASSERT(pictureID != SK_InvalidGenID && start > 0 && stop > 0);
-    return fLayerHash.find(GrCachedLayer::Key(pictureID, start, stop, ctm));
+    return fLayerHash.find(GrCachedLayer::Key(pictureID, start, stop, offset, ctm));
 }
 
 GrCachedLayer* GrLayerCache::findLayerOrCreate(uint32_t pictureID,
                                                int start, int stop,
+                                               const SkIPoint& offset,
                                                const SkMatrix& ctm) {
     SkASSERT(pictureID != SK_InvalidGenID && start > 0 && stop > 0);
-    GrCachedLayer* layer = fLayerHash.find(GrCachedLayer::Key(pictureID, start, stop, ctm));
+    GrCachedLayer* layer = fLayerHash.find(GrCachedLayer::Key(pictureID, start, stop, offset, ctm));
     if (NULL == layer) {
-        layer = this->createLayer(pictureID, start, stop, ctm);
+        layer = this->createLayer(pictureID, start, stop, offset, ctm);
     }
 
     return layer;
diff --git a/src/gpu/GrLayerCache.h b/src/gpu/GrLayerCache.h
index fc1467e120..15fa246c43 100644
--- a/src/gpu/GrLayerCache.h
+++ b/src/gpu/GrLayerCache.h
@@ -51,15 +51,17 @@ struct GrCachedLayer {
 public:
     // For SkTDynamicHash
     struct Key {
-        Key(uint32_t pictureID, int start, int stop, const SkMatrix& ctm) 
+        Key(uint32_t pictureID, int start, int stop, const SkIPoint& offset, const SkMatrix& ctm) 
         : fPictureID(pictureID)
         , fStart(start)
         , fStop(stop)
+        , fOffset(offset)
         , fCTM(ctm) {
             fCTM.getType(); // force initialization of type so hashes match
 
             // Key needs to be tightly packed.
             GR_STATIC_ASSERT(sizeof(Key) == sizeof(uint32_t) + 2 * sizeof(int) + 
+                                            2 * sizeof(int32_t) +
                                             9 * sizeof(SkScalar) + sizeof(uint32_t));
         }
 
@@ -67,12 +69,14 @@ public:
             return fPictureID == other.fPictureID &&
                    fStart == other.fStart &&
                    fStop == other.fStop &&
+                   fOffset == other.fOffset &&
                    fCTM.cheapEqualTo(other.fCTM);
         }
 
         uint32_t pictureID() const { return fPictureID; }
         int start() const { return fStart; }
         int stop() const { return fStop; }
+        const SkIPoint& offset() const { return fOffset; }
         const SkMatrix& ctm() const { return fCTM; }
 
     private:
@@ -81,6 +85,8 @@ public:
         // The range of commands in the picture this layer represents
         const int      fStart;
         const int      fStop;
+        // The offset of the layer in device space
+        const SkIPoint fOffset;
         // The CTM applied to this layer in the picture
         SkMatrix       fCTM;
     };
@@ -91,8 +97,9 @@ public:
     }
 
     // GrCachedLayer proper
-    GrCachedLayer(uint32_t pictureID, int start, int stop, const SkMatrix& ctm) 
-        : fKey(pictureID, start, stop, ctm)
+    GrCachedLayer(uint32_t pictureID, int start, int stop,
+                  const SkIPoint& offset, const SkMatrix& ctm) 
+        : fKey(pictureID, start, stop, offset, ctm)
         , fTexture(NULL)
         , fRect(GrIRect16::MakeEmpty())
         , fPlot(NULL)
@@ -107,6 +114,7 @@ public:
     uint32_t pictureID() const { return fKey.pictureID(); }
     int start() const { return fKey.start(); }
     int stop() const { return fKey.stop(); }
+    const SkIPoint& offset() const { return fKey.offset(); }
     const SkMatrix& ctm() const { return fKey.ctm(); }
 
     void setTexture(GrTexture* texture, const GrIRect16& rect) {
@@ -171,9 +179,11 @@ public:
     // elements by the GrContext
     void freeAll();
 
-    GrCachedLayer* findLayer(uint32_t pictureID, int start, int stop, const SkMatrix& ctm);
+    GrCachedLayer* findLayer(uint32_t pictureID, int start, int stop, 
+                             const SkIPoint& offset, const SkMatrix& ctm);
     GrCachedLayer* findLayerOrCreate(uint32_t pictureID,
                                      int start, int stop, 
+                                     const SkIPoint& offset,
                                      const SkMatrix& ctm);
 
     // Inform the cache that layer's cached image is now required. 
@@ -227,9 +237,9 @@ private:
     int fPlotLocks[kNumPlotsX * kNumPlotsY];
 
     void initAtlas();
-    GrCachedLayer* createLayer(uint32_t pictureID, int start, int stop, const SkMatrix& ctm);
+    GrCachedLayer* createLayer(uint32_t pictureID, int start, int stop, 
+                               const SkIPoint& offset, const SkMatrix& ctm);
 
-public:
     void purgeAll();
 
     // Remove all the layers (and unlock any resources) associated with 'pictureID'
diff --git a/src/gpu/GrLayerHoister.cpp b/src/gpu/GrLayerHoister.cpp
index 49ca338bb2..a29d91ac9d 100644
--- a/src/gpu/GrLayerHoister.cpp
+++ b/src/gpu/GrLayerHoister.cpp
@@ -91,11 +91,18 @@ void GrLayerHoister::DrawLayers(const SkPicture* picture,
             // info.fCTM maps the layer's top/left to the origin.
             // Since this layer is atlased, the top/left corner needs
             // to be offset to the correct location in the backing texture.
+            SkMatrix initialCTM;
+            initialCTM.setTranslate(SkIntToScalar(-layer->offset().fX), 
+                                    SkIntToScalar(-layer->offset().fY));
+            initialCTM.postTranslate(bound.fLeft, bound.fTop);
+            
+            atlasCanvas->translate(SkIntToScalar(-layer->offset().fX), 
+                                   SkIntToScalar(-layer->offset().fY));
             atlasCanvas->translate(bound.fLeft, bound.fTop);
             atlasCanvas->concat(layer->ctm());
 
             SkRecordPartialDraw(*picture->fRecord.get(), atlasCanvas, bound,
-                                layer->start()+1, layer->stop());
+                                layer->start()+1, layer->stop(), initialCTM);
 
             atlasCanvas->restore();
         }
@@ -126,10 +133,16 @@ void GrLayerHoister::DrawLayers(const SkPicture* picture,
 
         layerCanvas->clear(SK_ColorTRANSPARENT);
 
+        SkMatrix initialCTM;
+        initialCTM.setTranslate(SkIntToScalar(-layer->offset().fX), 
+                                SkIntToScalar(-layer->offset().fY));
+
+        layerCanvas->translate(SkIntToScalar(-layer->offset().fX), 
+                               SkIntToScalar(-layer->offset().fY));
         layerCanvas->concat(layer->ctm());
 
         SkRecordPartialDraw(*picture->fRecord.get(), layerCanvas, bound,
-                            layer->start()+1, layer->stop());
+                            layer->start()+1, layer->stop(), initialCTM);
 
         layerCanvas->flush();
     }
@@ -151,6 +164,7 @@ void GrLayerHoister::UnlockLayers(GrLayerCache* layerCache, const SkPicture* pic
         GrCachedLayer* layer = layerCache->findLayer(picture->uniqueID(),
                                                      info.fSaveLayerOpID,
                                                      info.fRestoreOpID,
+                                                     info.fOffset,
                                                      info.fOriginXform);
         layerCache->unlock(layer);
     }
diff --git a/src/gpu/GrPictureUtils.cpp b/src/gpu/GrPictureUtils.cpp
index 8810eb8a07..0cc1f1e065 100644
--- a/src/gpu/GrPictureUtils.cpp
+++ b/src/gpu/GrPictureUtils.cpp
@@ -126,8 +126,6 @@ private:
             dst.fOffset = SkIPoint::Make(newClip.fLeft, newClip.fTop);
             dst.fOriginXform = *fCTM;
             dst.fOriginXform.postConcat(src.fOriginXform);
-            dst.fOriginXform.postTranslate(SkIntToScalar(-newClip.fLeft), 
-                                           SkIntToScalar(-newClip.fTop));
 
             if (NULL == src.fPaint) {
                 dst.fPaint = NULL;
@@ -191,8 +189,6 @@ private:
         slInfo.fSize = SkISize::Make(si.fBounds.width(), si.fBounds.height());
         slInfo.fOffset = SkIPoint::Make(si.fBounds.fLeft, si.fBounds.fTop);
         slInfo.fOriginXform = *fCTM;
-        slInfo.fOriginXform.postTranslate(SkIntToScalar(-si.fBounds.fLeft),
-                                          SkIntToScalar(-si.fBounds.fTop));
 
         if (NULL == si.fPaint) {
             slInfo.fPaint = NULL;
diff --git a/src/gpu/GrPictureUtils.h b/src/gpu/GrPictureUtils.h
index 1c6897ce77..55b294ac69 100644
--- a/src/gpu/GrPictureUtils.h
+++ b/src/gpu/GrPictureUtils.h
@@ -26,8 +26,8 @@ public:
         uint32_t fPictureID;
         // The size of the saveLayer
         SkISize fSize;
-        // The matrix state in which this layer's draws must occur. It already incorporates
-        // the translation needed to map the layer's top-left point to the origin.
+        // The matrix state in which this layer's draws must occur. It does not
+        // include the translation needed to map the layer's top-left point to the origin.
         SkMatrix fOriginXform;
         // The offset that needs to be passed to drawBitmap to correctly
         // position the pre-rendered layer. It is in device space.
diff --git a/src/gpu/SkGpuDevice.cpp b/src/gpu/SkGpuDevice.cpp
index 122af65ff9..b719f84278 100644
--- a/src/gpu/SkGpuDevice.cpp
+++ b/src/gpu/SkGpuDevice.cpp
@@ -1887,7 +1887,8 @@ bool SkGpuDevice::EXPERIMENTAL_drawPicture(SkCanvas* mainCanvas, const SkPicture
 
             GrCachedLayer* layer = fContext->getLayerCache()->findLayerOrCreate(picture->uniqueID(), 
                                                                                 info.fSaveLayerOpID, 
-                                                                                info.fRestoreOpID, 
+                                                                                info.fRestoreOpID,
+                                                                                info.fOffset,
                                                                                 info.fOriginXform);
 
             GrReplacements::ReplacementInfo* layerInfo = replacements.push();