Fix handling of MaskFilter matrices

1) extend GrFPArgs to track pre/post local matrices, add helpers for
   creating pre/post wrapper args

2) add a SkShaderBase helper (totalLocalMatrix) to centralize the LM
   sandwich logic.

3) update call sites to use the above

4) rename SkMatrixFilter::makeWithLocalMatrix -> makeWithMatrix, to
   disambiguate vs. SkShader::makeWithLocalMatrix.

BUG=skia:7744

Change-Id: Ib2b7b007e6924979b00649dde7c94ef4b34771f1
Reviewed-on: https://skia-review.googlesource.com/119330
Commit-Queue: Florin Malita <fmalita@chromium.org>
Reviewed-by: Brian Salomon <bsalomon@google.com>

2 files changed, 13 insertions, 22 deletions

diff --git a/src/core/SkBitmapDevice.cpp b/src/core/SkBitmapDevice.cpp
index 5f84ba1aec..26cdc39313 100644
--- a/src/core/SkBitmapDevice.cpp
+++ b/src/core/SkBitmapDevice.cpp
@@ -487,7 +487,7 @@ void SkBitmapDevice::drawDevice(SkBaseDevice* device, int x, int y, const SkPain
     // todo: can we unify with similar adjustment in SkGpuDevice?
     SkTCopyOnFirstWrite<SkPaint> paint(origPaint);
     if (paint->getMaskFilter()) {
-        paint.writable()->setMaskFilter(paint->getMaskFilter()->makeWithLocalMatrix(this->ctm()));
+        paint.writable()->setMaskFilter(paint->getMaskFilter()->makeWithMatrix(this->ctm()));
     }
     this->drawSprite(static_cast<SkBitmapDevice*>(device)->fBitmap, x, y, *paint);
 }
@@ -546,7 +546,7 @@ void SkBitmapDevice::drawSpecial(SkSpecialImage* src, int x, int y, const SkPain
     }
 
     if (paint->getMaskFilter()) {
-        paint.writable()->setMaskFilter(paint->getMaskFilter()->makeWithLocalMatrix(this->ctm()));
+        paint.writable()->setMaskFilter(paint->getMaskFilter()->makeWithMatrix(this->ctm()));
     }
 
     if (!clipImage) {
diff --git a/src/core/SkMaskFilter.cpp b/src/core/SkMaskFilter.cpp
index e1805637a9..8e555f37ad 100644
--- a/src/core/SkMaskFilter.cpp
+++ b/src/core/SkMaskFilter.cpp
@@ -635,9 +635,9 @@ void SkCombineMF::toString(SkString* str) const {
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
-class SkLocalMatrixMF : public SkMaskFilterBase {
+class SkMatrixMF : public SkMaskFilterBase {
 public:
-    SkLocalMatrixMF(sk_sp<SkMaskFilter> filter, const SkMatrix& lm)
+    SkMatrixMF(sk_sp<SkMaskFilter> filter, const SkMatrix& lm)
         : fFilter(std::move(filter))
         , fLM(lm)
     {}
@@ -657,7 +657,7 @@ public:
     SkMask::Format getFormat() const override { return as_MFB(fFilter)->getFormat(); }
 
     void toString(SkString* str) const override {
-        str->set("SkLocalMatrixMF:");
+        str->set("SkMatrixMF:");
     }
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLocalMatrixMF)
@@ -665,16 +665,7 @@ public:
 protected:
 #if SK_SUPPORT_GPU
     std::unique_ptr<GrFragmentProcessor> onAsFragmentProcessor(const GrFPArgs& args) const override{
-        GrFPArgs newArgs = args;
-
-        SkMatrix storage;
-        if (args.fLocalMatrix) {
-            storage.setConcat(*args.fLocalMatrix, fLM);
-            newArgs.fLocalMatrix = &storage;
-        } else {
-            newArgs.fLocalMatrix = &fLM;
-        }
-        return as_MFB(fFilter)->asFragmentProcessor(newArgs);
+        return as_MFB(fFilter)->asFragmentProcessor(args.makeWithPostLocalMatrix(fLM));
     }
 
     bool onHasFragmentProcessor() const override {
@@ -695,11 +686,11 @@ private:
     typedef SkMaskFilterBase INHERITED;
 };
 
-sk_sp<SkFlattenable> SkLocalMatrixMF::CreateProc(SkReadBuffer& buffer) {
-    SkMatrix lm;
-    buffer.readMatrix(&lm);
+sk_sp<SkFlattenable> SkMatrixMF::CreateProc(SkReadBuffer& buffer) {
+    SkMatrix m;
+    buffer.readMatrix(&m);
     auto filter = buffer.readMaskFilter();
-    return filter ? filter->makeWithLocalMatrix(lm) : nullptr;
+    return filter ? filter->makeWithMatrix(m) : nullptr;
 }
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
@@ -735,16 +726,16 @@ sk_sp<SkMaskFilter> SkMaskFilter::MakeCombine(sk_sp<SkMaskFilter> dst, sk_sp<SkM
     return sk_sp<SkMaskFilter>(new SkCombineMF(std::move(dst), std::move(src), mode));
 }
 
-sk_sp<SkMaskFilter> SkMaskFilter::makeWithLocalMatrix(const SkMatrix& lm) const {
+sk_sp<SkMaskFilter> SkMaskFilter::makeWithMatrix(const SkMatrix& lm) const {
     sk_sp<SkMaskFilter> me = sk_ref_sp(const_cast<SkMaskFilter*>(this));
     if (lm.isIdentity()) {
         return me;
     }
-    return sk_sp<SkMaskFilter>(new SkLocalMatrixMF(std::move(me), lm));
+    return sk_sp<SkMaskFilter>(new SkMatrixMF(std::move(me), lm));
 }
 
 void SkMaskFilter::InitializeFlattenables() {
-    SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkLocalMatrixMF)
+    SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkMatrixMF)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkComposeMF)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkCombineMF)
     sk_register_blur_maskfilter_createproc();