Revert "remove toString"

This reverts commit 5191880cbf.

Reason for revert: broke flutter

Original change's description:
> remove toString
> 
> toString may have been used by obsolete debugger only
> find out if that is so
> 
> R=​brianosman@google.com,bsalomon@google.com
> 
> Docs-Preview: https://skia.org/?cl=119894
> Bug:830651
> Change-Id: I737f19b7d3fbc869bea2f443fa3b5ed7c1393ffd
> Reviewed-on: https://skia-review.googlesource.com/119894
> Commit-Queue: Cary Clark <caryclark@google.com>
> Reviewed-by: Brian Salomon <bsalomon@google.com>

TBR=bsalomon@google.com,brianosman@google.com,caryclark@google.com,caryclark@skia.org

Change-Id: I9f81de6c3615ee0608bcea9081b77239b4b8816c
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 830651
Reviewed-on: https://skia-review.googlesource.com/129340
Reviewed-by: Cary Clark <caryclark@google.com>
Commit-Queue: Cary Clark <caryclark@google.com>

docs/SkBitmap_Reference.bmh

@@ -3438,6 +3438,38 @@ SK_DEBUG is defined at compile time.
 
 # ------------------------------------------------------------------------------
 
+#Method void toString(SkString* str) const;
+#In Utility
+#Line # converts Bitmap to machine readable form ##
+
+Creates string representation of Bitmap. The representation is read by
+internal debugging tools.
+
+#Param str  storage for string representation ##
+
+#Example
+    SkBitmap bitmap;
+    int width = 6;
+    int height = 11;
+    bitmap.allocPixels(SkImageInfo::MakeN32Premul(width, height));
+    SkString string;
+    bitmap.toString(&string);
+    SkString match;
+    match.printf("(%d, %d)", width, height);
+    int start = string.find(match.c_str());
+    if (start >= 0) {
+        SkString whStr(&string.c_str()[start], match.size());
+        SkDebugf("bitmap dimensions %s\n", whStr.c_str());
+    }
+    #StdOut
+    bitmap dimensions (6, 11)
+    ##
+##
+
+#SeeAlso SkPaint::toString
+
+##
+
 #Class SkBitmap ##
 
 #Topic Bitmap ##

docs/SkImage_Reference.bmh

@@ -1749,6 +1749,39 @@ Returns nullptr if Image contents are not encoded.
 #Line # rarely called management functions ##
 ##
 
+#Method const char* toString(SkString* string) const
+#In Utility
+#Line # converts Image to machine readable form ##
+Appends Image description to string, including unique ID, width, height, and
+whether the image is opaque.
+
+#Param string  storage for description; existing content is preserved ##
+
+#Return string appended with Image description ##
+
+#Example
+#Image 4
+    struct {
+        const char* name;
+        sk_sp<SkImage> image;
+    } tests[] = { { "image", image }, { "bitmap", SkImage::MakeFromBitmap(source) },
+          { "texture", SkImage::MakeFromTexture(canvas->getGrContext(), backEndTexture,
+                            kTopLeft_GrSurfaceOrigin, kN32_SkColorType, kOpaque_SkAlphaType,
+                            nullptr) } };
+    SkString string;
+    SkPaint paint;
+    for (const auto& test : tests ) {
+        string.printf("%s: ", test.name);
+        test.image ? (void) test.image->toString(&string) : string.append("no image");
+        canvas->drawString(string, 10, 20, paint);
+        canvas->translate(0, 20);
+    }
+##
+
+#SeeAlso SkPaint::toString
+
+#Method ##
+
 # ------------------------------------------------------------------------------
 
 #Method sk_sp<SkImage> makeSubset(const SkIRect& subset) const

docs/SkMatrix_Reference.bmh

@@ -4103,7 +4103,40 @@ matrix != nearlyEqual
 ##
 ##
 
-#SeeAlso SkPath::dump
+#SeeAlso toString
+
+##
+
+# ------------------------------------------------------------------------------
+
+#Method void toString(SkString* str) const
+#In Utility
+#Line # converts Matrix to machine readable form ##
+Creates string representation of Matrix. Floating point values
+are written with limited precision; it may not be possible to reconstruct
+original Matrix from output.
+
+#Param str  storage for string representation of Matrix ##
+
+#Example
+    SkMatrix matrix;
+    matrix.setRotate(45);
+    SkString mStr, neStr;
+    matrix.toString(&mStr);
+    SkMatrix nearlyEqual;
+    nearlyEqual.setAll(0.7071f, -0.7071f, 0,   0.7071f, 0.7071f, 0,   0, 0, 1);
+    nearlyEqual.toString(&neStr);
+    SkDebugf("mStr  %s\n", mStr.c_str());
+    SkDebugf("neStr %s\n", neStr.c_str());
+    SkDebugf("matrix %c= nearlyEqual\n", matrix == nearlyEqual ? '=' : '!');
+#StdOut
+mStr  [  0.7071  -0.7071   0.0000][  0.7071   0.7071   0.0000][  0.0000   0.0000   1.0000]
+neStr [  0.7071  -0.7071   0.0000][  0.7071   0.7071   0.0000][  0.0000   0.0000   1.0000]
+matrix != nearlyEqual
+##
+##
+
+#SeeAlso dump
 
 ##
 

docs/SkPaint_Reference.bmh

@@ -5106,6 +5106,36 @@ Paint may draw to.
 #Line # rarely called management functions ##
 ##
 
+#Method void toString(SkString* str) const
+#In Utility
+#Line # converts Paint to machine readable form ##
+
+Creates string representation of Paint. The representation is read by
+internal debugging tools.
+
+#Param str  storage for string representation of Paint ##
+
+#Example
+    SkPaint paint;
+    SkString str;
+    paint.toString(&str);
+    const char textSize[] = "TextSize:";
+    const int trailerSize = strlen("</dd><dt>");
+    int textSizeLoc = str.find(textSize) + strlen(textSize) + trailerSize;
+    const char* sizeStart = &str.c_str()[textSizeLoc];
+    int textSizeEnd = SkStrFind(sizeStart, "</dd>");
+    SkDebugf("text size = %.*s\n", textSizeEnd, sizeStart);
+
+    #StdOut
+    text size = 12
+    ##
+
+##
+
+#SeeAlso SkPathEffect::toString SkMaskFilter::toString SkColorFilter::toString SkImageFilter::toString
+
+##
+
 # ------------------------------------------------------------------------------
 
 #Class SkPaint ##

docs/undocumented.bmh

@@ -95,6 +95,8 @@ FT_Load_Glyph
 
 #Topic Color_Filter
 #Class SkColorFilter
+#Method void toString(SkString* str) const
+##
 #Class ##
 ##
 
@@ -287,6 +289,8 @@ FT_Load_Glyph
 
 #Topic Image_Filter
 #Class SkImageFilter
+#Method void toString(SkString* str) const
+##
 #Class ##
 #Topic ##
 
@@ -325,6 +329,8 @@ FT_Load_Glyph
 
 #Topic Mask_Filter
 #Class SkMaskFilter
+#Method void toString(SkString* str) const
+##
 #Class ##
 #Topic ##
 
@@ -434,6 +440,8 @@ FT_Load_Glyph
 
 #Topic Path_Effect
     #Class SkPathEffect
+    #Method void toString(SkString* str) const
+    ##
     #Class ##
 #Topic ##
 

gm/imagefiltersbase.cpp

@@ -32,6 +32,7 @@ public:
         return sk_sp<SkImageFilter>(new FailImageFilter);
     }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(FailImageFilter)
 
 protected:
@@ -56,6 +57,11 @@ sk_sp<SkFlattenable> FailImageFilter::CreateProc(SkReadBuffer& buffer) {
     return FailImageFilter::Make();
 }
 
+void FailImageFilter::toString(SkString* str) const {
+    str->appendf("FailImageFilter: (");
+    str->append(")");
+}
+
 class IdentityImageFilter : public SkImageFilter {
 public:
     class Registrar {
@@ -70,6 +76,7 @@ public:
         return sk_sp<SkImageFilter>(new IdentityImageFilter(std::move(input)));
     }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(IdentityImageFilter)
 
 protected:
@@ -95,6 +102,11 @@ sk_sp<SkFlattenable> IdentityImageFilter::CreateProc(SkReadBuffer& buffer) {
     return IdentityImageFilter::Make(common.getInput(0));
 }
 
+void IdentityImageFilter::toString(SkString* str) const {
+    str->appendf("IdentityImageFilter: (");
+    str->append(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 static void draw_paint(SkCanvas* canvas, const SkRect& r, sk_sp<SkImageFilter> imf) {

include/core/SkBitmap.h

@@ -1246,6 +1246,13 @@ public:
         bool allocPixelRef(SkBitmap* bitmap) override;
     };
 
+    /** Creates string representation of SkBitmap. The representation is read by
+        internal debugging tools.
+
+        @param str  storage for string representation
+    */
+    void toString(SkString* str) const;
+
 private:
     enum Flags {
         kImageIsVolatile_Flag   = 0x02,

include/core/SkColorFilter.h

@@ -138,6 +138,8 @@ public:
         return this->filterColor(SK_ColorTRANSPARENT) != SK_ColorTRANSPARENT;
     }
 
+    virtual void toString(SkString* str) const = 0;
+
     SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
     SK_DEFINE_FLATTENABLE_TYPE(SkColorFilter)
 

include/core/SkDrawLooper.h

@@ -96,6 +96,7 @@ public:
      */
     virtual bool asABlurShadow(BlurShadowRec*) const;
 
+    virtual void toString(SkString* str) const = 0;
     SK_DEFINE_FLATTENABLE_TYPE(SkDrawLooper)
 
 protected:

include/core/SkImage.h

@@ -727,6 +727,14 @@ public:
     */
     sk_sp<SkData> refEncodedData() const;
 
+    /** Appends SkImage description to string, including unique ID, width, height, and
+        whether the image is opaque.
+
+        @param string  storage for description; existing content is preserved
+        @return        string appended with SkImage description
+    */
+    const char* toString(SkString* string) const;
+
     /** Returns subset of SkImage. subset must be fully contained by SkImage dimensions().
         The implementation may share pixels, or may copy them.
 

include/core/SkImageFilter.h

@@ -97,6 +97,7 @@ public:
             : fRect(rect), fFlags(flags) {}
         uint32_t flags() const { return fFlags; }
         const SkRect& rect() const { return fRect; }
+        void toString(SkString* str) const;
 
         /**
          *  Apply this cropRect to the imageBounds. If a given edge of the cropRect is not
@@ -248,8 +249,7 @@ public:
                                                  SkFilterQuality quality,
                                                  sk_sp<SkImageFilter> input);
 
-    // Deprecated; used only by chrome
+    virtual void toString(SkString* str) const = 0;
-    virtual void toString(SkString* ) const {}
     SK_DEFINE_FLATTENABLE_TYPE(SkImageFilter)
     SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()
 

include/core/SkMaskFilter.h

@@ -59,6 +59,7 @@ public:
      */
     sk_sp<SkMaskFilter> makeWithMatrix(const SkMatrix&) const;
 
+    virtual void toString(SkString* str) const = 0;
     SK_DEFINE_FLATTENABLE_TYPE(SkMaskFilter)
 
 private:

include/core/SkMatrix.h

@@ -1575,6 +1575,14 @@ public:
     */
     void dump() const;
 
+    /** Creates string representation of SkMatrix. Floating point values
+        are written with limited precision; it may not be possible to reconstruct
+        original SkMatrix from output.
+
+        @param str  storage for string representation of SkMatrix
+    */
+    void toString(SkString* str) const;
+
     /** Returns the minimum scaling factor of SkMatrix by decomposing the scaling and
         skewing elements.
         Returns -1 if scale factor overflows or SkMatrix contains perspective.

include/core/SkPaint.h

@@ -1598,6 +1598,13 @@ public:
     const SkRect& doComputeFastBounds(const SkRect& orig, SkRect* storage,
                                       Style style) const;
 
+    /** Creates string representation of SkPaint. The representation is read by
+        internal debugging tools.
+
+        @param str  storage for string representation of SkPaint
+    */
+    void toString(SkString* str) const;
+
 private:
     typedef const SkGlyph& (*GlyphCacheProc)(SkGlyphCache*, const char**);
 

include/core/SkPathEffect.h

@@ -145,6 +145,7 @@ public:
 
     virtual DashType asADash(DashInfo* info) const;
 
+    virtual void toString(SkString* str) const = 0;
     SK_DEFINE_FLATTENABLE_TYPE(SkPathEffect)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK

include/effects/Sk1DPathEffect.h

@@ -61,6 +61,7 @@ public:
     virtual bool filterPath(SkPath*, const SkPath&,
                             SkStrokeRec*, const SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPath1DPathEffect)
 
 protected:

include/effects/Sk2DPathEffect.h

@@ -39,6 +39,8 @@ protected:
     explicit Sk2DPathEffect(const SkMatrix& mat);
     void flatten(SkWriteBuffer&) const override;
 
+    void toString(SkString* str) const override;
+
 private:
     SkMatrix    fMatrix, fInverse;
     bool        fMatrixIsInvertible;
@@ -63,6 +65,7 @@ public:
     virtual bool filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec*, const SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLine2DPathEffect)
 
 protected:
@@ -90,6 +93,7 @@ public:
         return sk_sp<SkPathEffect>(new SkPath2DPathEffect(matrix, path));
     }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPath2DPathEffect)
 
 protected:

include/effects/SkColorFilterImageFilter.h

@@ -18,6 +18,7 @@ public:
                                      sk_sp<SkImageFilter> input,
                                      const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorFilterImageFilter)
 
 protected:

include/effects/SkComposeImageFilter.h

@@ -16,6 +16,7 @@ public:
 
     SkRect computeFastBounds(const SkRect& src) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposeImageFilter)
 
 protected:

include/effects/SkCornerPathEffect.h

@@ -27,6 +27,7 @@ public:
     virtual bool filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec*, const SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkCornerPathEffect)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK

include/effects/SkDiscretePathEffect.h

@@ -34,6 +34,7 @@ public:
     virtual bool filterPath(SkPath* dst, const SkPath& src,
                             SkStrokeRec*, const SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDiscretePathEffect)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK

include/effects/SkDisplacementMapEffect.h

@@ -41,6 +41,8 @@ public:
     SkIRect onFilterNodeBounds(const SkIRect&, const SkMatrix& ctm,
                                MapDirection, const SkIRect* inputRect) const override;
 
+    void toString(SkString* str) const override;
+
 protected:
     sk_sp<SkSpecialImage> onFilterImage(SkSpecialImage* source, const Context&,
                                         SkIPoint* offset) const override;

include/effects/SkDropShadowImageFilter.h

@@ -29,6 +29,7 @@ public:
                                      const CropRect* cropRect = nullptr);
 
     SkRect computeFastBounds(const SkRect&) const override;
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDropShadowImageFilter)
 
 protected:

include/effects/SkImageSource.h

@@ -21,6 +21,7 @@ public:
 
     SkRect computeFastBounds(const SkRect& src) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkImageSource)
 
 protected:

include/effects/SkLayerDrawLooper.h

@@ -75,6 +75,8 @@ public:
 
     bool asABlurShadow(BlurShadowRec* rec) const override;
 
+    void toString(SkString* str) const override;
+
     Factory getFactory() const override { return CreateProc; }
     static sk_sp<SkFlattenable> CreateProc(SkReadBuffer& buffer);
 

include/effects/SkLumaColorFilter.h

@@ -33,6 +33,7 @@ public:
             GrContext*, const GrColorSpaceInfo&) const override;
 #endif
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLumaColorFilter)
 
 protected:

include/effects/SkMagnifierImageFilter.h

@@ -18,6 +18,7 @@ public:
                                      sk_sp<SkImageFilter> input,
                                      const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMagnifierImageFilter)
 
 protected:

include/effects/SkMatrixConvolutionImageFilter.h

@@ -67,6 +67,7 @@ public:
                                      sk_sp<SkImageFilter> input,
                                      const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMatrixConvolutionImageFilter)
 
 protected:

include/effects/SkMergeImageFilter.h

@@ -24,6 +24,7 @@ public:
         return Make(array, 2, cropRect);
     }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMergeImageFilter)
 
 protected:

include/effects/SkMorphologyImageFilter.h

@@ -61,6 +61,7 @@ public:
                                      sk_sp<SkImageFilter> input,
                                      const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDilateImageFilter)
 
 protected:
@@ -82,6 +83,7 @@ public:
                                      sk_sp<SkImageFilter> input,
                                      const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkErodeImageFilter)
 
 protected:

include/effects/SkOffsetImageFilter.h

@@ -19,6 +19,7 @@ public:
 
     SkRect computeFastBounds(const SkRect& src) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkOffsetImageFilter)
 
 protected:

include/effects/SkOverdrawColorFilter.h

@@ -32,6 +32,8 @@ public:
             GrContext*, const GrColorSpaceInfo&) const override;
 #endif
 
+    void toString(SkString* str) const override;
+
     static sk_sp<SkFlattenable> CreateProc(SkReadBuffer& buffer);
     Factory getFactory() const override { return CreateProc; }
     SK_DECLARE_FLATTENABLE_REGISTRAR_GROUP()

include/effects/SkPaintImageFilter.h

@@ -26,6 +26,7 @@ public:
 
     bool affectsTransparentBlack() const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPaintImageFilter)
 
 protected:

include/effects/SkPictureImageFilter.h

@@ -24,6 +24,7 @@ public:
      */
     static sk_sp<SkImageFilter> Make(sk_sp<SkPicture> picture, const SkRect& cropRect);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkPictureImageFilter)
 
 protected:

include/effects/SkTileImageFilter.h

@@ -27,6 +27,7 @@ public:
                                MapDirection, const SkIRect* inputRect) const override;
     SkRect computeFastBounds(const SkRect& src) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTileImageFilter)
 
 protected:

include/effects/SkToSRGBColorFilter.h

@@ -26,6 +26,7 @@ public:
             GrContext*, const GrColorSpaceInfo&) const override;
 #endif
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkToSRGBColorFilter)
 
 private:

samplecode/ClockFaceView.cpp

@@ -85,6 +85,10 @@ public:
         return true;
     }
 
+    void toString(SkString* str) const override {
+        str->appendf("InverseFillPE: ()");
+    }
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(InverseFillPE)
 
 private:

src/core/SkBitmap.cpp

@@ -633,6 +633,33 @@ void SkBitmap::validate() const {
 }
 #endif
 
+#include "SkString.h"
+void SkBitmap::toString(SkString* str) const {
+
+    static const char* gColorTypeNames[kLastEnum_SkColorType + 1] = {
+        "UNKNOWN", "A8", "565", "4444", "RGBA", "BGRA", "INDEX8",
+    };
+
+    str->appendf("bitmap: ((%d, %d) %s", this->width(), this->height(),
+                 gColorTypeNames[this->colorType()]);
+
+    str->append(" (");
+    if (this->isOpaque()) {
+        str->append("opaque");
+    } else {
+        str->append("transparent");
+    }
+    if (this->isImmutable()) {
+        str->append(", immutable");
+    } else {
+        str->append(", not-immutable");
+    }
+    str->append(")");
+
+    str->appendf(" pixelref:%p", this->pixelRef());
+    str->append(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkBitmap::peekPixels(SkPixmap* pmap) const {

src/core/SkBlitter.cpp

@@ -861,6 +861,19 @@ public:
         typedef Context INHERITED;
     };
 
+    void toString(SkString* str) const override {
+        str->append("Sk3DShader: (");
+
+        if (fProxy) {
+            str->append("Proxy: ");
+            as_SB(fProxy)->toString(str);
+        }
+
+        this->INHERITED::toString(str);
+
+        str->append(")");
+    }
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(Sk3DShader)
 
 protected:

src/core/SkBlurImageFilter.cpp

@@ -41,6 +41,7 @@ public:
 
     SkRect computeFastBounds(const SkRect&) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBlurImageFilterImpl)
 
 protected:
@@ -696,3 +697,15 @@ SkIRect SkBlurImageFilterImpl::onFilterNodeBounds(const SkIRect& src, const SkMa
     SkVector sigma = map_sigma(fSigma, ctm);
     return src.makeOutset(SkScalarCeilToInt(sigma.x() * 3), SkScalarCeilToInt(sigma.y() * 3));
 }
+
+void SkBlurImageFilterImpl::toString(SkString* str) const {
+    str->appendf("SkBlurImageFilterImpl: (");
+    str->appendf("sigma: (%f, %f) tileMode: %d input (", fSigma.fWidth, fSigma.fHeight,
+                 static_cast<int>(fTileMode));
+
+    if (this->getInput(0)) {
+        this->getInput(0)->toString(str);
+    }
+
+    str->append("))");
+}

src/core/SkBlurMF.cpp

@@ -77,6 +77,7 @@ public:
     void computeFastBounds(const SkRect&, SkRect*) const override;
     bool asABlur(BlurRec*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBlurMaskFilterImpl)
 
 protected:
@@ -991,6 +992,23 @@ sk_sp<GrTextureProxy> SkBlurMaskFilterImpl::filterMaskGPU(GrContext* context,
 
 #endif // SK_SUPPORT_GPU
 
+
+void SkBlurMaskFilterImpl::toString(SkString* str) const {
+    str->append("SkBlurMaskFilterImpl: (");
+
+    str->append("sigma: ");
+    str->appendScalar(fSigma);
+    str->append(" ");
+
+    static const char* gStyleName[kLastEnum_SkBlurStyle + 1] = {
+        "normal", "solid", "outer", "inner"
+    };
+
+    str->appendf("style: %s ", gStyleName[fBlurStyle]);
+    str->appendf("respectCTM: %s ", fRespectCTM ? "true" : "false");
+    str->append(")");
+}
+
 void sk_register_blur_maskfilter_createproc() {
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkBlurMaskFilterImpl)
 }

src/core/SkColorFilter.cpp

@@ -98,6 +98,15 @@ public:
         return fOuter->getFlags() & fInner->getFlags();
     }
 
+    void toString(SkString* str) const override {
+        SkString outerS, innerS;
+        fOuter->toString(&outerS);
+        fInner->toString(&innerS);
+        // These strings can be long.  SkString::appendf has limitations.
+        str->append(SkStringPrintf("SkComposeColorFilter: outer(%s) inner(%s)", outerS.c_str(),
+                                   innerS.c_str()));
+    }
+
     void onAppendStages(SkRasterPipeline* p, SkColorSpace* dst, SkArenaAlloc* scratch,
                         bool shaderIsOpaque) const override {
         bool innerIsOpaque = shaderIsOpaque;
@@ -216,6 +225,8 @@ public:
     }
 #endif
 
+    void toString(SkString* str) const override;
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSRGBGammaColorFilter)
 
     void onAppendStages(SkRasterPipeline* p, SkColorSpace*, SkArenaAlloc* alloc,
@@ -256,6 +267,10 @@ sk_sp<SkFlattenable> SkSRGBGammaColorFilter::CreateProc(SkReadBuffer& buffer) {
     return sk_sp<SkFlattenable>(new SkSRGBGammaColorFilter(static_cast<Direction>(dir)));
 }
 
+void SkSRGBGammaColorFilter::toString(SkString* str) const {
+    str->append("srgbgamma");
+}
+
 template <SkSRGBGammaColorFilter::Direction dir>
 sk_sp<SkColorFilter> MakeSRGBGammaCF() {
     static SkColorFilter* gSingleton = new SkSRGBGammaColorFilter(dir);

src/core/SkColorMatrixFilterRowMajor255.cpp

@@ -299,6 +299,19 @@ std::unique_ptr<GrFragmentProcessor> SkColorMatrixFilterRowMajor255::asFragmentP
 
 #endif
 
+void SkColorMatrixFilterRowMajor255::toString(SkString* str) const {
+    str->append("SkColorMatrixFilterRowMajor255: ");
+
+    str->append("matrix: (");
+    for (int i = 0; i < 20; ++i) {
+        str->appendScalar(fMatrix[i]);
+        if (i < 19) {
+            str->append(", ");
+        }
+    }
+    str->append(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkColorFilter> SkColorFilter::MakeMatrixFilterRowMajor255(const SkScalar array[20]) {

src/core/SkColorMatrixFilterRowMajor255.h

@@ -27,6 +27,8 @@ public:
             GrContext*, const GrColorSpaceInfo&) const override;
 #endif
 
+    void toString(SkString* str) const override;
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorMatrixFilter)
 
 protected:

src/core/SkDraw_vertices.cpp

@@ -77,6 +77,8 @@ public:
 
     bool isOpaque() const override { return fIsOpaque; }
 
+    void toString(SkString* str) const override;
+
     // For serialization.  This will never be called.
     Factory getFactory() const override { SK_ABORT("not reached"); return nullptr; }
 
@@ -97,6 +99,14 @@ private:
     typedef SkShaderBase INHERITED;
 };
 
+void SkTriColorShader::toString(SkString* str) const {
+    str->append("SkTriColorShader: (");
+
+    this->INHERITED::toString(str);
+
+    str->append(")");
+}
+
 static bool SK_WARN_UNUSED_RESULT
 update_tricolor_matrix(const SkMatrix& ctmInv, const SkPoint pts[], const SkPM4f colors[],
                        int index0, int index1, int index2, Matrix43* result) {

src/core/SkImageFilter.cpp

@@ -28,6 +28,35 @@
 #include "SkGr.h"
 #endif
 
+void SkImageFilter::CropRect::toString(SkString* str) const {
+    if (!fFlags) {
+        return;
+    }
+
+    str->appendf("cropRect (");
+    if (fFlags & CropRect::kHasLeft_CropEdge) {
+        str->appendf("%.2f, ", fRect.fLeft);
+    } else {
+        str->appendf("X, ");
+    }
+    if (fFlags & CropRect::kHasTop_CropEdge) {
+        str->appendf("%.2f, ", fRect.fTop);
+    } else {
+        str->appendf("X, ");
+    }
+    if (fFlags & CropRect::kHasWidth_CropEdge) {
+        str->appendf("%.2f, ", fRect.width());
+    } else {
+        str->appendf("X, ");
+    }
+    if (fFlags & CropRect::kHasHeight_CropEdge) {
+        str->appendf("%.2f", fRect.height());
+    } else {
+        str->appendf("X");
+    }
+    str->appendf(") ");
+}
+
 void SkImageFilter::CropRect::applyTo(const SkIRect& imageBounds,
                                       const SkMatrix& ctm,
                                       bool embiggen,

src/core/SkLocalMatrixImageFilter.cpp

@@ -67,3 +67,8 @@ const {
     }
     return this->refMe();
 }
+
+void SkLocalMatrixImageFilter::toString(SkString* str) const {
+    str->append("SkLocalMatrixImageFilter: (");
+    str->append(")");
+}

src/core/SkLocalMatrixImageFilter.h

@@ -18,6 +18,7 @@ class SkLocalMatrixImageFilter : public SkImageFilter {
 public:
     static sk_sp<SkImageFilter> Make(const SkMatrix& localM, sk_sp<SkImageFilter> input);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLocalMatrixImageFilter)
 
 protected:

src/core/SkMaskFilter.cpp

@@ -405,6 +405,7 @@ public:
     }
 
     SkMask::Format getFormat() const override { return SkMask::kA8_Format; }
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposeMF)
 
 protected:
@@ -469,6 +470,10 @@ sk_sp<SkFlattenable> SkComposeMF::CreateProc(SkReadBuffer& buffer) {
     return SkMaskFilter::MakeCompose(std::move(outer), std::move(inner));
 }
 
+void SkComposeMF::toString(SkString* str) const {
+    str->set("SkComposeMF:");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 class SkCombineMF : public SkMaskFilterBase {
@@ -493,6 +498,7 @@ public:
 
     SkMask::Format getFormat() const override { return SkMask::kA8_Format; }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkCombineMF)
 
 protected:
@@ -619,6 +625,10 @@ sk_sp<SkFlattenable> SkCombineMF::CreateProc(SkReadBuffer& buffer) {
     return SkMaskFilter::MakeCombine(std::move(dst), std::move(src), mode);
 }
 
+void SkCombineMF::toString(SkString* str) const {
+    str->set("SkCombineMF:");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 class SkMatrixMF : public SkMaskFilterBase {
@@ -642,6 +652,10 @@ public:
 
     SkMask::Format getFormat() const override { return as_MFB(fFilter)->getFormat(); }
 
+    void toString(SkString* str) const override {
+        str->set("SkMatrixMF:");
+    }
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkLocalMatrixMF)
 
 protected:

src/core/SkMatrix.cpp

@@ -1659,10 +1659,14 @@ size_t SkMatrix::readFromMemory(const void* buffer, size_t length) {
 
 void SkMatrix::dump() const {
     SkString str;
-    str.appendf("[%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f]",
+    this->toString(&str);
+    SkDebugf("%s\n", str.c_str());
+}
+
+void SkMatrix::toString(SkString* str) const {
+    str->appendf("[%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f][%8.4f %8.4f %8.4f]",
              fMat[0], fMat[1], fMat[2], fMat[3], fMat[4], fMat[5],
              fMat[6], fMat[7], fMat[8]);
-    SkDebugf("%s\n", str.c_str());
 }
 
 ///////////////////////////////////////////////////////////////////////////////

src/core/SkMatrixImageFilter.cpp

@@ -143,3 +143,25 @@ SkIRect SkMatrixImageFilter::onFilterNodeBounds(const SkIRect& src, const SkMatr
 
     return result;
 }
+
+void SkMatrixImageFilter::toString(SkString* str) const {
+    str->appendf("SkMatrixImageFilter: (");
+
+    str->appendf("transform: (%f %f %f %f %f %f %f %f %f)",
+                 fTransform[SkMatrix::kMScaleX],
+                 fTransform[SkMatrix::kMSkewX],
+                 fTransform[SkMatrix::kMTransX],
+                 fTransform[SkMatrix::kMSkewY],
+                 fTransform[SkMatrix::kMScaleY],
+                 fTransform[SkMatrix::kMTransY],
+                 fTransform[SkMatrix::kMPersp0],
+                 fTransform[SkMatrix::kMPersp1],
+                 fTransform[SkMatrix::kMPersp2]);
+
+    str->append("<dt>FilterLevel:</dt><dd>");
+    static const char* gFilterLevelStrings[] = { "None", "Low", "Medium", "High" };
+    str->append(gFilterLevelStrings[fFilterQuality]);
+    str->append("</dd>");
+
+    str->appendf(")");
+}

src/core/SkMatrixImageFilter.h

@@ -31,6 +31,7 @@ public:
 
     SkRect computeFastBounds(const SkRect&) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkMatrixImageFilter)
 
 protected:

src/core/SkModeColorFilter.cpp

@@ -31,6 +31,13 @@ SkModeColorFilter::SkModeColorFilter(SkColor color, SkBlendMode mode) {
     fPMColor = SkPreMultiplyColor(fColor);
 }
 
+void SkModeColorFilter::toString(SkString* str) const {
+    str->append("SkModeColorFilter: color: 0x");
+    str->appendHex(fColor);
+    str->append(" mode: ");
+    str->append(SkBlendMode_Name(fMode));
+}
+
 bool SkModeColorFilter::asColorMode(SkColor* color, SkBlendMode* mode) const {
     if (color) {
         *color = fColor;

src/core/SkModeColorFilter.h

@@ -22,6 +22,8 @@ public:
     bool asColorMode(SkColor*, SkBlendMode*) const override;
     uint32_t getFlags() const override;
 
+    void toString(SkString* str) const override;
+
 #if SK_SUPPORT_GPU
     std::unique_ptr<GrFragmentProcessor> asFragmentProcessor(
             GrContext*, const GrColorSpaceInfo&) const override;

src/core/SkPaint.cpp

@@ -1384,6 +1384,155 @@ const SkRect& SkPaint::doComputeFastBounds(const SkRect& origSrc,
     return *storage;
 }
 
+void SkPaint::toString(SkString* str) const {
+    str->append("<dl><dt>SkPaint:</dt><dd><dl>");
+
+    SkTypeface* typeface = this->getTypeface();
+    if (typeface) {
+        SkDynamicMemoryWStream ostream;
+        typeface->serialize(&ostream);
+        std::unique_ptr<SkStreamAsset> istream(ostream.detachAsStream());
+
+        SkFontDescriptor descriptor;
+        if (!SkFontDescriptor::Deserialize(istream.get(), &descriptor)) {
+            str->append("<dt>FontDescriptor deserialization failed</dt>");
+        } else {
+            str->append("<dt>Font Family Name:</dt><dd>");
+            str->append(descriptor.getFamilyName());
+            str->append("</dd><dt>Font Full Name:</dt><dd>");
+            str->append(descriptor.getFullName());
+            str->append("</dd><dt>Font PS Name:</dt><dd>");
+            str->append(descriptor.getPostscriptName());
+            str->append("</dd>");
+        }
+    }
+
+    str->append("<dt>TextSize:</dt><dd>");
+    str->appendScalar(this->getTextSize());
+    str->append("</dd>");
+
+    str->append("<dt>TextScaleX:</dt><dd>");
+    str->appendScalar(this->getTextScaleX());
+    str->append("</dd>");
+
+    str->append("<dt>TextSkewX:</dt><dd>");
+    str->appendScalar(this->getTextSkewX());
+    str->append("</dd>");
+
+    SkPathEffect* pathEffect = this->getPathEffect();
+    if (pathEffect) {
+        str->append("<dt>PathEffect:</dt><dd>");
+        pathEffect->toString(str);
+        str->append("</dd>");
+    }
+
+    if (const auto* shader = as_SB(this->getShader())) {
+        str->append("<dt>Shader:</dt><dd>");
+        shader->toString(str);
+        str->append("</dd>");
+    }
+
+    if (!this->isSrcOver()) {
+        str->appendf("<dt>Xfermode:</dt><dd>%d</dd>", fBlendMode);
+    }
+
+    SkMaskFilter* maskFilter = this->getMaskFilter();
+    if (maskFilter) {
+        str->append("<dt>MaskFilter:</dt><dd>");
+        as_MFB(maskFilter)->toString(str);
+        str->append("</dd>");
+    }
+
+    SkColorFilter* colorFilter = this->getColorFilter();
+    if (colorFilter) {
+        str->append("<dt>ColorFilter:</dt><dd>");
+        colorFilter->toString(str);
+        str->append("</dd>");
+    }
+
+    SkDrawLooper* looper = this->getLooper();
+    if (looper) {
+        str->append("<dt>DrawLooper:</dt><dd>");
+        looper->toString(str);
+        str->append("</dd>");
+    }
+
+    SkImageFilter* imageFilter = this->getImageFilter();
+    if (imageFilter) {
+        str->append("<dt>ImageFilter:</dt><dd>");
+        imageFilter->toString(str);
+        str->append("</dd>");
+    }
+
+    str->append("<dt>Color:</dt><dd>0x");
+    SkColor color = this->getColor();
+    str->appendHex(color);
+    str->append("</dd>");
+
+    str->append("<dt>Stroke Width:</dt><dd>");
+    str->appendScalar(this->getStrokeWidth());
+    str->append("</dd>");
+
+    str->append("<dt>Stroke Miter:</dt><dd>");
+    str->appendScalar(this->getStrokeMiter());
+    str->append("</dd>");
+
+    str->append("<dt>Flags:</dt><dd>(");
+    if (this->getFlags()) {
+        bool needSeparator = false;
+        SkAddFlagToString(str, this->isAntiAlias(), "AntiAlias", &needSeparator);
+        SkAddFlagToString(str, this->isDither(), "Dither", &needSeparator);
+        SkAddFlagToString(str, this->isFakeBoldText(), "FakeBoldText", &needSeparator);
+        SkAddFlagToString(str, this->isLinearText(), "LinearText", &needSeparator);
+        SkAddFlagToString(str, this->isSubpixelText(), "SubpixelText", &needSeparator);
+        SkAddFlagToString(str, this->isLCDRenderText(), "LCDRenderText", &needSeparator);
+        SkAddFlagToString(str, this->isEmbeddedBitmapText(),
+                          "EmbeddedBitmapText", &needSeparator);
+        SkAddFlagToString(str, this->isAutohinted(), "Autohinted", &needSeparator);
+        SkAddFlagToString(str, this->isVerticalText(), "VerticalText", &needSeparator);
+    } else {
+        str->append("None");
+    }
+    str->append(")</dd>");
+
+    str->append("<dt>FilterLevel:</dt><dd>");
+    static const char* gFilterQualityStrings[] = { "None", "Low", "Medium", "High" };
+    str->append(gFilterQualityStrings[this->getFilterQuality()]);
+    str->append("</dd>");
+
+    str->append("<dt>TextAlign:</dt><dd>");
+    static const char* gTextAlignStrings[SkPaint::kAlignCount] = { "Left", "Center", "Right" };
+    str->append(gTextAlignStrings[this->getTextAlign()]);
+    str->append("</dd>");
+
+    str->append("<dt>CapType:</dt><dd>");
+    static const char* gStrokeCapStrings[SkPaint::kCapCount] = { "Butt", "Round", "Square" };
+    str->append(gStrokeCapStrings[this->getStrokeCap()]);
+    str->append("</dd>");
+
+    str->append("<dt>JoinType:</dt><dd>");
+    static const char* gJoinStrings[SkPaint::kJoinCount] = { "Miter", "Round", "Bevel" };
+    str->append(gJoinStrings[this->getStrokeJoin()]);
+    str->append("</dd>");
+
+    str->append("<dt>Style:</dt><dd>");
+    static const char* gStyleStrings[SkPaint::kStyleCount] = { "Fill", "Stroke", "StrokeAndFill" };
+    str->append(gStyleStrings[this->getStyle()]);
+    str->append("</dd>");
+
+    str->append("<dt>TextEncoding:</dt><dd>");
+    static const char* gTextEncodingStrings[] = { "UTF8", "UTF16", "UTF32", "GlyphID" };
+    str->append(gTextEncodingStrings[this->getTextEncoding()]);
+    str->append("</dd>");
+
+    str->append("<dt>Hinting:</dt><dd>");
+    static const char* gHintingStrings[] = { "None", "Slight", "Normal", "Full" };
+    str->append(gHintingStrings[this->getHinting()]);
+    str->append("</dd>");
+
+    str->append("</dd></dl></dl>");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 static bool has_thick_frame(const SkPaint& paint) {

src/core/SkPathEffect.cpp

@@ -51,10 +51,23 @@ protected:
     sk_sp<SkPathEffect> fPE0;
     sk_sp<SkPathEffect> fPE1;
 
+    void toString(SkString* str) const override;
+
 private:
     typedef SkPathEffect INHERITED;
 };
 
+void SkPairPathEffect::toString(SkString* str) const {
+    str->appendf("first: ");
+    if (fPE0) {
+        fPE0->toString(str);
+    }
+    str->appendf(" second: ");
+    if (fPE1) {
+        fPE1->toString(str);
+    }
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 /** \class SkComposePathEffect
@@ -91,6 +104,7 @@ public:
     }
 
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkComposePathEffect)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
@@ -116,6 +130,12 @@ sk_sp<SkFlattenable> SkComposePathEffect::CreateProc(SkReadBuffer& buffer) {
     return SkComposePathEffect::Make(std::move(pe0), std::move(pe1));
 }
 
+void SkComposePathEffect::toString(SkString* str) const {
+    str->appendf("SkComposePathEffect: (");
+    this->INHERITED::toString(str);
+    str->appendf(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 /** \class SkSumPathEffect
@@ -148,6 +168,7 @@ public:
     }
 
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSumPathEffect)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK
@@ -173,6 +194,12 @@ sk_sp<SkFlattenable> SkSumPathEffect::CreateProc(SkReadBuffer& buffer) {
     return SkSumPathEffect::Make(pe0, pe1);
 }
 
+void SkSumPathEffect::toString(SkString* str) const {
+    str->appendf("SkSumPathEffect: (");
+    this->INHERITED::toString(str);
+    str->appendf(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkPathEffect> SkPathEffect::MakeSum(sk_sp<SkPathEffect> first, sk_sp<SkPathEffect> second) {

src/core/SkStringUtils.cpp

@@ -9,6 +9,16 @@
 #include "SkStringUtils.h"
 #include "SkUtils.h"
 
+void SkAddFlagToString(SkString* string, bool flag, const char* flagStr, bool* needSeparator) {
+    if (flag) {
+        if (*needSeparator) {
+            string->append("|");
+        }
+        string->append(flagStr);
+        *needSeparator = true;
+    }
+}
+
 void SkAppendScalar(SkString* str, SkScalar value, SkScalarAsStringType asType) {
     switch (asType) {
         case kHex_SkScalarAsStringType:

src/core/SkStringUtils.h

@@ -12,6 +12,16 @@
 
 class SkString;
 
+/**
+ * Add 'flagStr' to 'string' and set 'needSeparator' to true only if 'flag' is
+ * true. If 'needSeparator' is true append a '|' before 'flagStr'. This method
+ * is used to streamline the creation of ASCII flag strings within the toString
+ * methods.
+ */
+void SkAddFlagToString(SkString* string, bool flag,
+                       const char* flagStr, bool* needSeparator);
+
+
 enum SkScalarAsStringType {
     kDec_SkScalarAsStringType,
     kHex_SkScalarAsStringType,

src/effects/Sk1DPathEffect.cpp

@@ -194,6 +194,14 @@ SkScalar SkPath1DPathEffect::next(SkPath* dst, SkScalar distance,
     return fAdvance;
 }
 
+
+void SkPath1DPathEffect::toString(SkString* str) const {
+    str->appendf("SkPath1DPathEffect: (");
+    // TODO: add path and style
+    str->appendf("advance: %.2f phase %.2f", fAdvance, fInitialOffset);
+    str->appendf(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkPathEffect> SkPath1DPathEffect::Make(const SkPath& path, SkScalar advance, SkScalar phase,

src/effects/Sk2DPathEffect.cpp

@@ -74,6 +74,13 @@ void Sk2DPathEffect::flatten(SkWriteBuffer& buffer) const {
     buffer.writeMatrix(fMatrix);
 }
 
+void Sk2DPathEffect::toString(SkString* str) const {
+    str->appendf("(matrix: %.2f %.2f %.2f %.2f %.2f %.2f %.2f %.2f %.2f)",
+            fMatrix[SkMatrix::kMScaleX], fMatrix[SkMatrix::kMSkewX],  fMatrix[SkMatrix::kMTransX],
+            fMatrix[SkMatrix::kMSkewY],  fMatrix[SkMatrix::kMScaleY], fMatrix[SkMatrix::kMTransY],
+            fMatrix[SkMatrix::kMPersp0], fMatrix[SkMatrix::kMPersp1], fMatrix[SkMatrix::kMPersp2]);
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 bool SkLine2DPathEffect::filterPath(SkPath* dst, const SkPath& src,
@@ -110,6 +117,14 @@ void SkLine2DPathEffect::flatten(SkWriteBuffer &buffer) const {
     buffer.writeScalar(fWidth);
 }
 
+
+void SkLine2DPathEffect::toString(SkString* str) const {
+    str->appendf("SkLine2DPathEffect: (");
+    this->INHERITED::toString(str);
+    str->appendf("width: %f", fWidth);
+    str->appendf(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 SkPath2DPathEffect::SkPath2DPathEffect(const SkMatrix& m, const SkPath& p)
@@ -133,3 +148,11 @@ void SkPath2DPathEffect::next(const SkPoint& loc, int u, int v,
                               SkPath* dst) const {
     dst->addPath(fPath, loc.fX, loc.fY);
 }
+
+void SkPath2DPathEffect::toString(SkString* str) const {
+    str->appendf("SkPath2DPathEffect: (");
+    this->INHERITED::toString(str);
+    // TODO: print out path information
+    str->appendf(")");
+}
+

src/effects/SkAlphaThresholdFilter.cpp

@@ -31,6 +31,7 @@ public:
                                SkScalar outerThreshold, sk_sp<SkImageFilter> input,
                                const CropRect* cropRect = nullptr);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkAlphaThresholdFilterImpl)
     friend void SkAlphaThresholdFilter::InitializeFlattenables();
 
@@ -280,3 +281,10 @@ const {
     }
     return this->refMe();
 }
+
+void SkAlphaThresholdFilterImpl::toString(SkString* str) const {
+    str->appendf("SkAlphaThresholdImageFilter: (");
+    str->appendf("inner: %f outer: %f", fInnerThreshold, fOuterThreshold);
+    str->append(")");
+}
+

src/effects/SkArithmeticImageFilter.cpp

@@ -37,6 +37,7 @@ public:
                               sk_sp<SkImageFilter> inputs[2], const CropRect* cropRect)
             : INHERITED(inputs, 2, cropRect), fK{k1, k2, k3, k4}, fEnforcePMColor(enforcePMColor) {}
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(ArithmeticImageFilterImpl)
 
 protected:
@@ -431,6 +432,22 @@ const {
     return this->refMe();
 }
 
+void ArithmeticImageFilterImpl::toString(SkString* str) const {
+    str->appendf("SkArithmeticImageFilter: (");
+    str->appendf("K[]: (%f %f %f %f)", fK[0], fK[1], fK[2], fK[3]);
+    if (this->getInput(0)) {
+        str->appendf("foreground: (");
+        this->getInput(0)->toString(str);
+        str->appendf(")");
+    }
+    if (this->getInput(1)) {
+        str->appendf("background: (");
+        this->getInput(1)->toString(str);
+        str->appendf(")");
+    }
+    str->append(")");
+}
+
 sk_sp<SkImageFilter> SkArithmeticImageFilter::Make(float k1, float k2, float k3, float k4,
                                                    bool enforcePMColor,
                                                    sk_sp<SkImageFilter> background,

src/effects/SkColorFilterImageFilter.cpp

@@ -144,3 +144,18 @@ bool SkColorFilterImageFilter::onIsColorFilterNode(SkColorFilter** filter) const
 bool SkColorFilterImageFilter::affectsTransparentBlack() const {
     return fColorFilter->affectsTransparentBlack();
 }
+
+void SkColorFilterImageFilter::toString(SkString* str) const {
+    str->appendf("SkColorFilterImageFilter: (");
+
+    str->appendf("input: (");
+
+    if (this->getInput(0)) {
+        this->getInput(0)->toString(str);
+    }
+
+    str->appendf(") color filter: ");
+    fColorFilter->toString(str);
+
+    str->append(")");
+}

src/effects/SkColorMatrixFilter.cpp

@@ -72,6 +72,8 @@ public:
     }
 #endif
 
+    void toString(SkString* str) const override { fMatrixFilter->toString(str); }
+
 private:
     SkColor              fMul, fAdd;
     sk_sp<SkColorFilter> fMatrixFilter;

src/effects/SkComposeImageFilter.cpp

@@ -88,3 +88,17 @@ sk_sp<SkFlattenable> SkComposeImageFilter::CreateProc(SkReadBuffer& buffer) {
     return SkComposeImageFilter::Make(common.getInput(0), common.getInput(1));
 }
 
+void SkComposeImageFilter::toString(SkString* str) const {
+    SkImageFilter* outer = getInput(0);
+    SkImageFilter* inner = getInput(1);
+
+    str->appendf("SkComposeImageFilter: (");
+
+    str->appendf("outer: ");
+    outer->toString(str);
+
+    str->appendf("inner: ");
+    inner->toString(str);
+
+    str->appendf(")");
+}

src/effects/SkCornerPathEffect.cpp

@@ -151,3 +151,9 @@ sk_sp<SkFlattenable> SkCornerPathEffect::CreateProc(SkReadBuffer& buffer) {
 void SkCornerPathEffect::flatten(SkWriteBuffer& buffer) const {
     buffer.writeScalar(fRadius);
 }
+
+void SkCornerPathEffect::toString(SkString* str) const {
+    str->appendf("SkCornerPathEffect: (");
+    str->appendf("radius: %.2f", fRadius);
+    str->appendf(")");
+}

src/effects/SkDashImpl.h

@@ -21,6 +21,7 @@ public:
 
     DashType asADash(DashInfo* info) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDashImpl)
 
 #ifdef SK_BUILD_FOR_ANDROID_FRAMEWORK

src/effects/SkDashPathEffect.cpp

@@ -380,6 +380,18 @@ sk_sp<SkFlattenable> SkDashImpl::CreateProc(SkReadBuffer& buffer) {
     return nullptr;
 }
 
+void SkDashImpl::toString(SkString* str) const {
+    str->appendf("SkDashPathEffect: (");
+    str->appendf("count: %d phase %.2f intervals: (", fCount, fPhase);
+    for (int i = 0; i < fCount; ++i) {
+        str->appendf("%.2f", fIntervals[i]);
+        if (i < fCount-1) {
+            str->appendf(", ");
+        }
+    }
+    str->appendf("))");
+}
+
 //////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkPathEffect> SkDashPathEffect::Make(const SkScalar intervals[], int count, SkScalar phase) {

src/effects/SkDiscretePathEffect.cpp

@@ -143,3 +143,9 @@ void SkDiscretePathEffect::flatten(SkWriteBuffer& buffer) const {
     buffer.writeScalar(fPerterb);
     buffer.writeUInt(fSeedAssist);
 }
+
+void SkDiscretePathEffect::toString(SkString* str) const {
+    str->appendf("SkDiscretePathEffect: (");
+    str->appendf("segLength: %.2f deviation: %.2f seed %d", fSegLength, fPerterb, fSeedAssist);
+    str->append(")");
+}

src/effects/SkDisplacementMapEffect.cpp

@@ -404,6 +404,20 @@ SkIRect SkDisplacementMapEffect::onFilterBounds(const SkIRect& src, const SkMatr
     return src;
 }
 
+void SkDisplacementMapEffect::toString(SkString* str) const {
+    str->appendf("SkDisplacementMapEffect: (");
+    str->appendf("scale: %f ", fScale);
+    str->appendf("displacement: (");
+    if (this->getDisplacementInput()) {
+        this->getDisplacementInput()->toString(str);
+    }
+    str->appendf(") color: (");
+    if (this->getColorInput()) {
+        this->getColorInput()->toString(str);
+    }
+    str->appendf("))");
+}
+
 ///////////////////////////////////////////////////////////////////////////////
 
 #if SK_SUPPORT_GPU

src/effects/SkDropShadowImageFilter.cpp

@@ -159,3 +159,24 @@ SkIRect SkDropShadowImageFilter::onFilterNodeBounds(const SkIRect& src, const Sk
     return dst;
 }
 
+void SkDropShadowImageFilter::toString(SkString* str) const {
+    str->appendf("SkDropShadowImageFilter: (");
+
+    str->appendf("dX: %f ", fDx);
+    str->appendf("dY: %f ", fDy);
+    str->appendf("sigmaX: %f ", fSigmaX);
+    str->appendf("sigmaY: %f ", fSigmaY);
+
+    str->append("Color: ");
+    str->appendHex(fColor);
+
+    static const char* gModeStrings[] = {
+        "kDrawShadowAndForeground", "kDrawShadowOnly"
+    };
+
+    static_assert(kShadowModeCount == SK_ARRAY_COUNT(gModeStrings), "enum_mismatch");
+
+    str->appendf(" mode: %s", gModeStrings[fShadowMode]);
+
+    str->append(")");
+}

src/effects/SkEmbossMaskFilter.cpp

@@ -140,3 +140,22 @@ void SkEmbossMaskFilter::flatten(SkWriteBuffer& buffer) const {
     buffer.writeByteArray(&tmpLight, sizeof(tmpLight));
     buffer.writeScalar(fBlurSigma);
 }
+
+void SkEmbossMaskFilter::toString(SkString* str) const {
+    str->append("SkEmbossMaskFilter: (");
+
+    str->append("direction: (");
+    str->appendScalar(fLight.fDirection[0]);
+    str->append(", ");
+    str->appendScalar(fLight.fDirection[1]);
+    str->append(", ");
+    str->appendScalar(fLight.fDirection[2]);
+    str->append(") ");
+
+    str->appendf("ambient: %d specular: %d ",
+        fLight.fAmbient, fLight.fSpecular);
+
+    str->append("blurSigma: ");
+    str->appendScalar(fBlurSigma);
+    str->append(")");
+}

src/effects/SkEmbossMaskFilter.h

@@ -32,6 +32,7 @@ public:
     bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
                     SkIPoint* margin) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmbossMaskFilter)
 
 protected:

src/effects/SkHighContrastFilter.cpp

@@ -45,6 +45,8 @@ public:
                         SkArenaAlloc* scratch,
                         bool shaderIsOpaque) const override;
 
+    void toString(SkString* str) const override;
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkHighContrast_Filter)
 
 protected:
@@ -155,6 +157,10 @@ sk_sp<SkColorFilter> SkHighContrastFilter::Make(
     return sk_make_sp<SkHighContrast_Filter>(config);
 }
 
+void SkHighContrast_Filter::toString(SkString* str) const {
+    str->append("SkHighContrastColorFilter ");
+}
+
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkHighContrastFilter)
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkHighContrast_Filter)
 SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END

src/effects/SkImageSource.cpp

@@ -157,3 +157,12 @@ SkIRect SkImageSource::onFilterNodeBounds(const SkIRect& src, const SkMatrix& ct
     return dstRect.roundOut();
 }
 
+void SkImageSource::toString(SkString* str) const {
+    str->appendf("SkImageSource: (");
+    str->appendf("src: (%f,%f,%f,%f) dst: (%f,%f,%f,%f) ",
+                 fSrcRect.fLeft, fSrcRect.fTop, fSrcRect.fRight, fSrcRect.fBottom,
+                 fDstRect.fLeft, fDstRect.fTop, fDstRect.fRight, fDstRect.fBottom);
+    str->appendf("image: (%d,%d)",
+                 fImage->width(), fImage->height());
+    str->append(")");
+}

src/effects/SkLayerDrawLooper.cpp

@@ -279,6 +279,62 @@ sk_sp<SkFlattenable> SkLayerDrawLooper::CreateProc(SkReadBuffer& buffer) {
     return builder.detach();
 }
 
+void SkLayerDrawLooper::toString(SkString* str) const {
+    str->appendf("SkLayerDrawLooper (%d): ", fCount);
+
+    Rec* rec = fRecs;
+    for (int i = 0; i < fCount; i++) {
+        str->appendf("%d: paintBits: (", i);
+        if (0 == rec->fInfo.fPaintBits) {
+            str->append("None");
+        } else if (kEntirePaint_Bits == rec->fInfo.fPaintBits) {
+            str->append("EntirePaint");
+        } else {
+            bool needSeparator = false;
+            SkAddFlagToString(str, SkToBool(kStyle_Bit & rec->fInfo.fPaintBits), "Style",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kTextSkewX_Bit & rec->fInfo.fPaintBits), "TextSkewX",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kPathEffect_Bit & rec->fInfo.fPaintBits), "PathEffect",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kMaskFilter_Bit & rec->fInfo.fPaintBits), "MaskFilter",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kShader_Bit & rec->fInfo.fPaintBits), "Shader",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kColorFilter_Bit & rec->fInfo.fPaintBits), "ColorFilter",
+                              &needSeparator);
+            SkAddFlagToString(str, SkToBool(kXfermode_Bit & rec->fInfo.fPaintBits), "Xfermode",
+                              &needSeparator);
+        }
+        str->append(") ");
+
+        static const char* gModeStrings[(int)SkBlendMode::kLastMode+1] = {
+            "kClear", "kSrc", "kDst", "kSrcOver", "kDstOver", "kSrcIn", "kDstIn",
+            "kSrcOut", "kDstOut", "kSrcATop", "kDstATop", "kXor", "kPlus",
+            "kMultiply", "kScreen", "kOverlay", "kDarken", "kLighten", "kColorDodge",
+            "kColorBurn", "kHardLight", "kSoftLight", "kDifference", "kExclusion"
+        };
+
+        str->appendf("mode: %s ", gModeStrings[(int)rec->fInfo.fColorMode]);
+
+        str->append("offset: (");
+        str->appendScalar(rec->fInfo.fOffset.fX);
+        str->append(", ");
+        str->appendScalar(rec->fInfo.fOffset.fY);
+        str->append(") ");
+
+        str->append("postTranslate: ");
+        if (rec->fInfo.fPostTranslate) {
+            str->append("true ");
+        } else {
+            str->append("false ");
+        }
+
+        rec->fPaint.toString(str);
+        rec = rec->fNext;
+    }
+}
+
 SkLayerDrawLooper::Builder::Builder()
         : fRecs(nullptr),
           fTopRec(nullptr),

src/effects/SkLightingImageFilter.cpp

@@ -530,6 +530,7 @@ public:
                                      sk_sp<SkImageFilter>,
                                      const CropRect*);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkDiffuseLightingImageFilter)
     SkScalar kd() const { return fKD; }
 
@@ -564,6 +565,7 @@ public:
                                      SkScalar ks, SkScalar shininess,
                                      sk_sp<SkImageFilter>, const CropRect*);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSpecularLightingImageFilter)
 
     SkScalar ks() const { return fKS; }
@@ -1369,6 +1371,12 @@ const {
     return this->refMe();
 }
 
+void SkDiffuseLightingImageFilter::toString(SkString* str) const {
+    str->appendf("SkDiffuseLightingImageFilter: (");
+    str->appendf("kD: %f\n", fKD);
+    str->append(")");
+}
+
 #if SK_SUPPORT_GPU
 std::unique_ptr<GrFragmentProcessor> SkDiffuseLightingImageFilter::makeFragmentProcessor(
         sk_sp<GrTextureProxy> proxy,
@@ -1518,6 +1526,12 @@ const {
     return this->refMe();
 }
 
+void SkSpecularLightingImageFilter::toString(SkString* str) const {
+    str->appendf("SkSpecularLightingImageFilter: (");
+    str->appendf("kS: %f shininess: %f", fKS, fShininess);
+    str->append(")");
+}
+
 #if SK_SUPPORT_GPU
 std::unique_ptr<GrFragmentProcessor> SkSpecularLightingImageFilter::makeFragmentProcessor(
         sk_sp<GrTextureProxy> proxy,

src/effects/SkLumaColorFilter.cpp

@@ -37,6 +37,10 @@ sk_sp<SkFlattenable> SkLumaColorFilter::CreateProc(SkReadBuffer&) {
 
 void SkLumaColorFilter::flatten(SkWriteBuffer&) const {}
 
+void SkLumaColorFilter::toString(SkString* str) const {
+    str->append("SkLumaColorFilter ");
+}
+
 #if SK_SUPPORT_GPU
 std::unique_ptr<GrFragmentProcessor> SkLumaColorFilter::asFragmentProcessor(
         GrContext*, const GrColorSpaceInfo&) const {

src/effects/SkMagnifierImageFilter.cpp

@@ -200,3 +200,11 @@ sk_sp<SkImageFilter> SkMagnifierImageFilter::onMakeColorSpace(SkColorSpaceXforme
     }
     return this->refMe();
 }
+
+void SkMagnifierImageFilter::toString(SkString* str) const {
+    str->appendf("SkMagnifierImageFilter: (");
+    str->appendf("src: (%f,%f,%f,%f) ",
+                 fSrcRect.fLeft, fSrcRect.fTop, fSrcRect.fRight, fSrcRect.fBottom);
+    str->appendf("inset: %f", fInset);
+    str->append(")");
+}

src/effects/SkMatrixConvolutionImageFilter.cpp

@@ -479,3 +479,18 @@ bool SkMatrixConvolutionImageFilter::affectsTransparentBlack() const {
     // pixels it will affect in object-space.
     return kRepeat_TileMode != fTileMode;
 }
+
+void SkMatrixConvolutionImageFilter::toString(SkString* str) const {
+    str->appendf("SkMatrixConvolutionImageFilter: (");
+    str->appendf("size: (%d,%d) kernel: (", fKernelSize.width(), fKernelSize.height());
+    for (int y = 0; y < fKernelSize.height(); y++) {
+        for (int x = 0; x < fKernelSize.width(); x++) {
+            str->appendf("%f ", fKernel[y * fKernelSize.width() + x]);
+        }
+    }
+    str->appendf(")");
+    str->appendf("gain: %f bias: %f ", fGain, fBias);
+    str->appendf("offset: (%d, %d) ", fKernelOffset.fX, fKernelOffset.fY);
+    str->appendf("convolveAlpha: %s", fConvolveAlpha ? "true" : "false");
+    str->append(")");
+}

src/effects/SkMergeImageFilter.cpp

@@ -121,3 +121,15 @@ void SkMergeImageFilter::flatten(SkWriteBuffer& buffer) const {
     this->INHERITED::flatten(buffer);
 }
 
+void SkMergeImageFilter::toString(SkString* str) const {
+    str->appendf("SkMergeImageFilter: (");
+
+    for (int i = 0; i < this->countInputs(); ++i) {
+        SkImageFilter* filter = this->getInput(i);
+        str->appendf("%d: (", i);
+        filter->toString(str);
+        str->appendf(")");
+    }
+
+    str->append(")");
+}

src/effects/SkMorphologyImageFilter.cpp

@@ -113,6 +113,18 @@ sk_sp<SkFlattenable> SkDilateImageFilter::CreateProc(SkReadBuffer& buffer) {
     return Make(width, height, common.getInput(0), &common.cropRect());
 }
 
+void SkErodeImageFilter::toString(SkString* str) const {
+    str->appendf("SkErodeImageFilter: (");
+    str->appendf("radius: (%d,%d)", this->radius().fWidth, this->radius().fHeight);
+    str->append(")");
+}
+
+void SkDilateImageFilter::toString(SkString* str) const {
+    str->appendf("SkDilateImageFilter: (");
+    str->appendf("radius: (%d,%d)", this->radius().fWidth, this->radius().fHeight);
+    str->append(")");
+}
+
 #if SK_SUPPORT_GPU
 
 ///////////////////////////////////////////////////////////////////////////////

src/effects/SkOffsetImageFilter.cpp

@@ -124,3 +124,13 @@ SkOffsetImageFilter::SkOffsetImageFilter(SkScalar dx, SkScalar dy,
     : INHERITED(&input, 1, cropRect) {
     fOffset.set(dx, dy);
 }
+
+void SkOffsetImageFilter::toString(SkString* str) const {
+    str->appendf("SkOffsetImageFilter: (");
+    str->appendf("offset: (%f, %f) ", fOffset.fX, fOffset.fY);
+    str->append("input: (");
+    if (this->getInput(0)) {
+        this->getInput(0)->toString(str);
+    }
+    str->append("))");
+}

src/effects/SkOverdrawColorFilter.cpp

@@ -36,6 +36,14 @@ void SkOverdrawColorFilter::onAppendStages(SkRasterPipeline* p,
     p->append(SkRasterPipeline::callback, ctx);
 }
 
+void SkOverdrawColorFilter::toString(SkString* str) const {
+    str->append("SkOverdrawColorFilter (");
+    for (int i = 0; i < kNumColors; i++) {
+        str->appendf("%d: %x\n", i, fColors[i]);
+    }
+    str->append(")");
+}
+
 void SkOverdrawColorFilter::flatten(SkWriteBuffer& buffer) const {
     buffer.writeByteArray(fColors, kNumColors * sizeof(SkPMColor));
 }

src/effects/SkPaintImageFilter.cpp

@@ -81,3 +81,9 @@ sk_sp<SkImageFilter> SkPaintImageFilter::onMakeColorSpace(SkColorSpaceXformer* x
 bool SkPaintImageFilter::affectsTransparentBlack() const {
     return true;
 }
+
+void SkPaintImageFilter::toString(SkString* str) const {
+    str->appendf("SkPaintImageFilter: (");
+    fPaint.toString(str);
+    str->append(")");
+}

src/effects/SkPictureImageFilter.cpp

@@ -130,3 +130,15 @@ sk_sp<SkImageFilter> SkPictureImageFilter::onMakeColorSpace(SkColorSpaceXformer*
 
     return sk_sp<SkImageFilter>(new SkPictureImageFilter(fPicture, fCropRect, std::move(dstCS)));
 }
+
+void SkPictureImageFilter::toString(SkString* str) const {
+    str->appendf("SkPictureImageFilter: (");
+    str->appendf("crop: (%f,%f,%f,%f) ",
+                 fCropRect.fLeft, fCropRect.fTop, fCropRect.fRight, fCropRect.fBottom);
+    if (fPicture) {
+        str->appendf("picture: (%f,%f,%f,%f)",
+                     fPicture->cullRect().fLeft, fPicture->cullRect().fTop,
+                     fPicture->cullRect().fRight, fPicture->cullRect().fBottom);
+    }
+    str->append(")");
+}

src/effects/SkShaderMaskFilter.cpp

@@ -27,6 +27,7 @@ public:
 
     bool asABlur(BlurRec*) const override { return false; }
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkShaderMF)
 
 protected:
@@ -46,6 +47,10 @@ private:
     typedef SkMaskFilter INHERITED;
 };
 
+void SkShaderMF::toString(SkString* str) const {
+    str->set("SkShaderMF:");
+}
+
 sk_sp<SkFlattenable> SkShaderMF::CreateProc(SkReadBuffer& buffer) {
     return SkShaderMaskFilter::Make(buffer.readShader());
 }

src/effects/SkTableColorFilter.cpp

@@ -90,6 +90,8 @@ public:
             GrContext*, const GrColorSpaceInfo&) const override;
 #endif
 
+    void toString(SkString* str) const override;
+
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTable_ColorFilter)
 
     enum {
@@ -138,6 +140,35 @@ private:
     typedef SkColorFilter INHERITED;
 };
 
+void SkTable_ColorFilter::toString(SkString* str) const {
+    const uint8_t* table = fStorage;
+    const uint8_t* tableA = gIdentityTable;
+    const uint8_t* tableR = gIdentityTable;
+    const uint8_t* tableG = gIdentityTable;
+    const uint8_t* tableB = gIdentityTable;
+    if (fFlags & kA_Flag) {
+        tableA = table; table += 256;
+    }
+    if (fFlags & kR_Flag) {
+        tableR = table; table += 256;
+    }
+    if (fFlags & kG_Flag) {
+        tableG = table; table += 256;
+    }
+    if (fFlags & kB_Flag) {
+        tableB = table;
+    }
+
+    str->append("SkTable_ColorFilter (");
+
+    for (int i = 0; i < 256; ++i) {
+        str->appendf("%d: %d,%d,%d,%d\n",
+                     i, tableR[i], tableG[i], tableB[i], tableA[i]);
+    }
+
+    str->append(")");
+}
+
 static const uint8_t gCountNibBits[] = {
     0, 1, 1, 2,
     1, 2, 2, 3,

src/effects/SkTableMaskFilter.cpp

@@ -18,6 +18,7 @@ public:
     SkMask::Format getFormat() const override;
     bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTableMaskFilterImpl)
 
 protected:
@@ -166,3 +167,15 @@ void SkTableMaskFilter::MakeClipTable(uint8_t table[256], uint8_t min,
     SkDebugf("\n\n");
 #endif
 }
+
+void SkTableMaskFilterImpl::toString(SkString* str) const {
+    str->append("SkTableMaskFilter: (");
+
+    str->append("table: ");
+    for (int i = 0; i < 255; ++i) {
+        str->appendf("%d, ", fTable[i]);
+    }
+    str->appendf("%d", fTable[255]);
+
+    str->append(")");
+}

src/effects/SkTileImageFilter.cpp

@@ -157,3 +157,17 @@ void SkTileImageFilter::flatten(SkWriteBuffer& buffer) const {
     buffer.writeRect(fSrcRect);
     buffer.writeRect(fDstRect);
 }
+
+void SkTileImageFilter::toString(SkString* str) const {
+    str->appendf("SkTileImageFilter: (");
+    str->appendf("src: %.2f %.2f %.2f %.2f",
+                 fSrcRect.fLeft, fSrcRect.fTop, fSrcRect.fRight, fSrcRect.fBottom);
+    str->appendf(" dst: %.2f %.2f %.2f %.2f",
+                 fDstRect.fLeft, fDstRect.fTop, fDstRect.fRight, fDstRect.fBottom);
+    if (this->getInput(0)) {
+        str->appendf("input: (");
+        this->getInput(0)->toString(str);
+        str->appendf(")");
+    }
+    str->append(")");
+}

src/effects/SkToSRGBColorFilter.cpp

@@ -71,6 +71,11 @@ void SkToSRGBColorFilter::flatten(SkWriteBuffer& buffer) const {
     buffer.writeDataAsByteArray(fSrcColorSpace->serialize().get());
 }
 
+void SkToSRGBColorFilter::toString(SkString* str) const {
+    // TODO
+    str->append("SkToSRGBColorFilter ");
+}
+
 #if SK_SUPPORT_GPU
 std::unique_ptr<GrFragmentProcessor> SkToSRGBColorFilter::asFragmentProcessor(
         GrContext*, const GrColorSpaceInfo&) const {

src/effects/SkTrimPE.h

@@ -18,6 +18,7 @@ public:
 
     bool filterPath(SkPath* dst, const SkPath& src, SkStrokeRec*, const SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTrimPE)
 
 protected:

src/effects/SkTrimPathEffect.cpp

@@ -97,6 +97,10 @@ sk_sp<SkFlattenable> SkTrimPE::CreateProc(SkReadBuffer& buffer) {
         (mode & 1) ? SkTrimPathEffect::Mode::kInverted : SkTrimPathEffect::Mode::kNormal);
 }
 
+void SkTrimPE::toString(SkString* str) const {
+    str->appendf("SkTrimPathEffect: (%g %g)", fStartT, fStopT);
+}
+
 //////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkPathEffect> SkTrimPathEffect::Make(SkScalar startT, SkScalar stopT, Mode mode) {

src/effects/SkXfermodeImageFilter.cpp

@@ -34,6 +34,7 @@ public:
     SkXfermodeImageFilter_Base(SkBlendMode mode, sk_sp<SkImageFilter> inputs[2],
                                const CropRect* cropRect);
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkXfermodeImageFilter_Base)
 
 protected:
@@ -248,6 +249,22 @@ void SkXfermodeImageFilter_Base::drawForeground(SkCanvas* canvas, SkSpecialImage
     canvas->drawPaint(paint);
 }
 
+void SkXfermodeImageFilter_Base::toString(SkString* str) const {
+    str->appendf("SkXfermodeImageFilter: (");
+    str->appendf("blendmode: (%d)", (int)fMode);
+    if (this->getInput(0)) {
+        str->appendf("foreground: (");
+        this->getInput(0)->toString(str);
+        str->appendf(")");
+    }
+    if (this->getInput(1)) {
+        str->appendf("background: (");
+        this->getInput(1)->toString(str);
+        str->appendf(")");
+    }
+    str->append(")");
+}
+
 #if SK_SUPPORT_GPU
 
 #include "effects/GrXfermodeFragmentProcessor.h"

src/gpu/GrTestUtils.h

@@ -74,6 +74,7 @@ public:
     bool filterPath(SkPath* dst, const SkPath&, SkStrokeRec* , const SkRect*) const override;
     DashType asADash(DashInfo* info) const override;
     Factory getFactory() const override { return nullptr; }
+    void toString(SkString*) const override {}
 
 private:
     TestDashPathEffect(const SkScalar* intervals, int count, SkScalar phase);

src/gpu/text/GrSDFMaskFilter.cpp

@@ -26,6 +26,7 @@ public:
 
     void computeFastBounds(const SkRect&, SkRect*) const override;
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(GrSDFMaskFilterImpl)
 
 protected:
@@ -86,6 +87,10 @@ sk_sp<SkFlattenable> GrSDFMaskFilterImpl::CreateProc(SkReadBuffer& buffer) {
     return GrSDFMaskFilter::Make();
 }
 
+void GrSDFMaskFilterImpl::toString(SkString* str) const {
+    str->append("GrSDFMaskFilterImpl: ()");
+}
+
 void gr_register_sdf_maskfilter_createproc() {
     SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(GrSDFMaskFilterImpl)
 }

src/image/SkImage.cpp

@@ -132,6 +132,12 @@ sk_sp<SkImage> SkImage::MakeFromEncoded(sk_sp<SkData> encoded, const SkIRect* su
 
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
+const char* SkImage::toString(SkString* str) const {
+    str->appendf("image: (id:%d (%d, %d) %s)", this->uniqueID(), this->width(), this->height(),
+                 this->isOpaque() ? "opaque" : "");
+    return str->c_str();
+}
+
 sk_sp<SkImage> SkImage::makeSubset(const SkIRect& subset) const {
     if (subset.isEmpty()) {
         return nullptr;

src/shaders/SkColorFilterShader.cpp

@@ -71,6 +71,19 @@ std::unique_ptr<GrFragmentProcessor> SkColorFilterShader::asFragmentProcessor(
 }
 #endif
 
+void SkColorFilterShader::toString(SkString* str) const {
+    str->append("SkColorFilterShader: (");
+
+    str->append("Shader: ");
+    as_SB(fShader)->toString(str);
+    str->append(" Filter: ");
+    // TODO: add "fFilter->toString(str);" once SkColorFilter::toString is added
+
+    this->INHERITED::toString(str);
+
+    str->append(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
 sk_sp<SkShader> SkShader::makeWithColorFilter(sk_sp<SkColorFilter> filter) const {

src/shaders/SkColorFilterShader.h

@@ -21,6 +21,7 @@ public:
     std::unique_ptr<GrFragmentProcessor> asFragmentProcessor(const GrFPArgs&) const override;
 #endif
 
+    void toString(SkString* str) const override;
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorFilterShader)
 
 protected:

src/shaders/SkColorShader.cpp

@@ -97,6 +97,17 @@ std::unique_ptr<GrFragmentProcessor> SkColorShader::asFragmentProcessor(
 
 #endif
 
+void SkColorShader::toString(SkString* str) const {
+    str->append("SkColorShader: (");
+
+    str->append("Color: ");
+    str->appendHex(fColor);
+
+    this->INHERITED::toString(str);
+
+    str->append(")");
+}
+
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 ///////////////////////////////////////////////////////////////////////////////////////////////////
 
@@ -212,6 +223,16 @@ std::unique_ptr<GrFragmentProcessor> SkColor4Shader::asFragmentProcessor(
 
 #endif
 
+void SkColor4Shader::toString(SkString* str) const {
+    str->append("SkColor4Shader: (");
+
+    str->append("RGBA:");
+    for (int i = 0; i < 4; ++i) {
+        str->appendf(" %g", fColor4.vec()[i]);
+    }
+    str->append(" )");
+}
+
 sk_sp<SkShader> SkColor4Shader::onMakeColorSpace(SkColorSpaceXformer* xformer) const {
     return SkShader::MakeColorShader(xformer->apply(fCachedByteColor));
 }