diff --git a/include/core/SkDraw.h b/include/core/SkDraw.h
index 5db4bf0..4ac7cf9 100644
--- a/include/core/SkDraw.h
+++ b/include/core/SkDraw.h
@@ -76,7 +76,7 @@
         solely to assist in computing the mask's bounds (if the mode requests that).
     */
     static bool DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
-                           SkMaskFilter* filter, const SkMatrix* filterMatrix,
+                           const SkMaskFilter*, const SkMatrix* filterMatrix,
                            SkMask* mask, SkMask::CreateMode mode,
                            SkPaint::Style style);
 
diff --git a/include/core/SkMaskFilter.h b/include/core/SkMaskFilter.h
index 02f5855..245de29 100644
--- a/include/core/SkMaskFilter.h
+++ b/include/core/SkMaskFilter.h
@@ -40,7 +40,7 @@
     /** Returns the format of the resulting mask that this subclass will return
         when its filterMask() method is called.
     */
-    virtual SkMask::Format getFormat() = 0;
+    virtual SkMask::Format getFormat() const = 0;
 
     /** Create a new mask by filter the src mask.
         If src.fImage == null, then do not allocate or create the dst image
@@ -56,7 +56,7 @@
         @return true if the dst mask was correctly created.
     */
     virtual bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
-                            SkIPoint* margin);
+                            SkIPoint* margin) const;
 
     enum BlurType {
         kNone_BlurType,    //!< this maskfilter is not a blur
@@ -91,7 +91,7 @@
      *  The default impl calls filterMask with the src mask having no image,
      *  but subclasses may override this if they can compute the rect faster.
      */
-    virtual void computeFastBounds(const SkRect& src, SkRect* dest);
+    virtual void computeFastBounds(const SkRect& src, SkRect* dest) const;
 
 protected:
     // empty for now, but lets get our subclass to remember to init us for the future
@@ -127,7 +127,7 @@
     virtual FilterReturn filterRectsToNine(const SkRect[], int count,
                                            const SkMatrix&,
                                            const SkIRect& clipBounds,
-                                           NinePatch*);
+                                           NinePatch*) const;
 
 private:
     friend class SkDraw;
@@ -139,7 +139,7 @@
      */
     bool filterPath(const SkPath& devPath, const SkMatrix& devMatrix,
                     const SkRasterClip&, SkBounder*, SkBlitter* blitter,
-                    SkPaint::Style style);
+                    SkPaint::Style style) const;
 
     typedef SkFlattenable INHERITED;
 };
diff --git a/include/effects/SkEmbossMaskFilter.h b/include/effects/SkEmbossMaskFilter.h
index 96c25b2..ce64473 100644
--- a/include/effects/SkEmbossMaskFilter.h
+++ b/include/effects/SkEmbossMaskFilter.h
@@ -27,10 +27,10 @@
 
     // overrides from SkMaskFilter
     //  This method is not exported to java.
-    virtual SkMask::Format getFormat();
+    virtual SkMask::Format getFormat() const SK_OVERRIDE;
     //  This method is not exported to java.
     virtual bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
-                            SkIPoint* margin);
+                            SkIPoint* margin) const SK_OVERRIDE;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkEmbossMaskFilter)
 
diff --git a/include/effects/SkKernel33MaskFilter.h b/include/effects/SkKernel33MaskFilter.h
index 41e73c9..9fcbb6a 100644
--- a/include/effects/SkKernel33MaskFilter.h
+++ b/include/effects/SkKernel33MaskFilter.h
@@ -15,11 +15,11 @@
     SkKernel33ProcMaskFilter(unsigned percent256 = 256)
         : fPercent256(percent256) {}
 
-    virtual uint8_t computeValue(uint8_t* const* srcRows) = 0;
+    virtual uint8_t computeValue(uint8_t* const* srcRows) const = 0;
 
-    // overrides from SkMaskFilter
-    virtual SkMask::Format getFormat();
-    virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*);
+    virtual SkMask::Format getFormat() const SK_OVERRIDE;
+    virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&,
+                            SkIPoint*) const SK_OVERRIDE;
 
 protected:
     SkKernel33ProcMaskFilter(SkFlattenableReadBuffer& rb);
@@ -42,7 +42,7 @@
     }
 
     // override from SkKernel33ProcMaskFilter
-    virtual uint8_t computeValue(uint8_t* const* srcRows);
+    virtual uint8_t computeValue(uint8_t* const* srcRows) const SK_OVERRIDE;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkKernel33MaskFilter)
 
diff --git a/include/effects/SkStippleMaskFilter.h b/include/effects/SkStippleMaskFilter.h
index b5d162e..be03c45 100644
--- a/include/effects/SkStippleMaskFilter.h
+++ b/include/effects/SkStippleMaskFilter.h
@@ -20,10 +20,10 @@
 
     virtual bool filterMask(SkMask* dst, const SkMask& src,
                             const SkMatrix& matrix,
-                            SkIPoint* margin) SK_OVERRIDE;
+                            SkIPoint* margin) const SK_OVERRIDE;
 
     // getFormat is from SkMaskFilter
-    virtual SkMask::Format getFormat() SK_OVERRIDE {
+    virtual SkMask::Format getFormat() const SK_OVERRIDE {
         return SkMask::kA8_Format;
     }
 
diff --git a/include/effects/SkTableMaskFilter.h b/include/effects/SkTableMaskFilter.h
index c407b40..feb3b13 100644
--- a/include/effects/SkTableMaskFilter.h
+++ b/include/effects/SkTableMaskFilter.h
@@ -22,8 +22,6 @@
     SkTableMaskFilter(const uint8_t table[256]);
     virtual ~SkTableMaskFilter();
 
-    void setTable(const uint8_t table[256]);
-
     /** Utility that sets the gamma table
      */
     static void MakeGammaTable(uint8_t table[256], SkScalar gamma);
@@ -45,9 +43,9 @@
         return SkNEW_ARGS(SkTableMaskFilter, (table));
     }
 
-    // overrides from SkMaskFilter
-    virtual SkMask::Format getFormat();
-    virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&, SkIPoint*);
+    virtual SkMask::Format getFormat() const SK_OVERRIDE;
+    virtual bool filterMask(SkMask*, const SkMask&, const SkMatrix&,
+                            SkIPoint*) const SK_OVERRIDE;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkTableMaskFilter)
 
diff --git a/samplecode/SampleText.cpp b/samplecode/SampleText.cpp
index 8ff36e4..6483218 100644
--- a/samplecode/SampleText.cpp
+++ b/samplecode/SampleText.cpp
@@ -31,8 +31,7 @@
 class ReduceNoise : public SkKernel33ProcMaskFilter {
 public:
     ReduceNoise(int percent256) : SkKernel33ProcMaskFilter(percent256) {}
-    virtual uint8_t computeValue(uint8_t* const* srcRows)
-    {
+    virtual uint8_t computeValue(uint8_t* const* srcRows) const {
         int c = srcRows[1][1];
         int min = 255, max = 0;
         for (int i = 0; i < 3; i++)
@@ -58,8 +57,7 @@
 class Darken : public SkKernel33ProcMaskFilter {
 public:
     Darken(int percent256) : SkKernel33ProcMaskFilter(percent256) {}
-    virtual uint8_t computeValue(uint8_t* const* srcRows)
-    {
+    virtual uint8_t computeValue(uint8_t* const* srcRows) const {
         int c = srcRows[1][1];
         float f = c / 255.f;
 
diff --git a/src/core/SkDraw.cpp b/src/core/SkDraw.cpp
index 3326b55..281c69c 100644
--- a/src/core/SkDraw.cpp
+++ b/src/core/SkDraw.cpp
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2006 The Android Open Source Project
  *
@@ -2651,7 +2650,7 @@
 #include "SkBlitter.h"
 
 static bool compute_bounds(const SkPath& devPath, const SkIRect* clipBounds,
-                           SkMaskFilter* filter, const SkMatrix* filterMatrix,
+                       const SkMaskFilter* filter, const SkMatrix* filterMatrix,
                            SkIRect* bounds) {
     if (devPath.isEmpty()) {
         return false;
@@ -2725,7 +2724,7 @@
 }
 
 bool SkDraw::DrawToMask(const SkPath& devPath, const SkIRect* clipBounds,
-                        SkMaskFilter* filter, const SkMatrix* filterMatrix,
+                        const SkMaskFilter* filter, const SkMatrix* filterMatrix,
                         SkMask* mask, SkMask::CreateMode mode,
                         SkPaint::Style style) {
     if (SkMask::kJustRenderImage_CreateMode != mode) {
diff --git a/src/core/SkMaskFilter.cpp b/src/core/SkMaskFilter.cpp
index eef2139..5de76c7 100644
--- a/src/core/SkMaskFilter.cpp
+++ b/src/core/SkMaskFilter.cpp
@@ -17,7 +17,7 @@
 SK_DEFINE_INST_COUNT(SkMaskFilter)
 
 bool SkMaskFilter::filterMask(SkMask*, const SkMask&, const SkMatrix&,
-                              SkIPoint*) {
+                              SkIPoint*) const {
     return false;
 }
 
@@ -192,7 +192,7 @@
 
 bool SkMaskFilter::filterPath(const SkPath& devPath, const SkMatrix& matrix,
                               const SkRasterClip& clip, SkBounder* bounder,
-                              SkBlitter* blitter, SkPaint::Style style) {
+                              SkBlitter* blitter, SkPaint::Style style) const {
     SkRect rects[2];
     int rectCount = 0;
     if (SkPaint::kFill_Style == style) {
@@ -254,7 +254,7 @@
 
 SkMaskFilter::FilterReturn
 SkMaskFilter::filterRectsToNine(const SkRect[], int count, const SkMatrix&,
-                                const SkIRect& clipBounds, NinePatch*) {
+                                const SkIRect& clipBounds, NinePatch*) const {
     return kUnimplemented_FilterReturn;
 }
 
@@ -262,7 +262,7 @@
     return kNone_BlurType;
 }
 
-void SkMaskFilter::computeFastBounds(const SkRect& src, SkRect* dst) {
+void SkMaskFilter::computeFastBounds(const SkRect& src, SkRect* dst) const {
     SkMask  srcM, dstM;
 
     srcM.fImage = NULL;
diff --git a/src/effects/SkBlurMaskFilter.cpp b/src/effects/SkBlurMaskFilter.cpp
index a3991ca..c49a785 100644
--- a/src/effects/SkBlurMaskFilter.cpp
+++ b/src/effects/SkBlurMaskFilter.cpp
@@ -17,18 +17,18 @@
                          uint32_t flags);
 
     // overrides from SkMaskFilter
-    virtual SkMask::Format getFormat() SK_OVERRIDE;
+    virtual SkMask::Format getFormat() const SK_OVERRIDE;
     virtual bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&,
-                            SkIPoint* margin) SK_OVERRIDE;
+                            SkIPoint* margin) const SK_OVERRIDE;
     virtual BlurType asABlur(BlurInfo*) const SK_OVERRIDE;
-    virtual void computeFastBounds(const SkRect& src, SkRect* dst) SK_OVERRIDE;
+    virtual void computeFastBounds(const SkRect&, SkRect*) const SK_OVERRIDE;
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkBlurMaskFilterImpl)
 
 protected:
     virtual FilterReturn filterRectsToNine(const SkRect[], int count, const SkMatrix&,
                                            const SkIRect& clipBounds,
-                                           NinePatch*) SK_OVERRIDE;
+                                           NinePatch*) const SK_OVERRIDE;
 
 private:
     SkScalar                    fRadius;
@@ -74,12 +74,13 @@
     SkASSERT(flags <= SkBlurMaskFilter::kAll_BlurFlag);
 }
 
-SkMask::Format SkBlurMaskFilterImpl::getFormat() {
+SkMask::Format SkBlurMaskFilterImpl::getFormat() const {
     return SkMask::kA8_Format;
 }
 
 bool SkBlurMaskFilterImpl::filterMask(SkMask* dst, const SkMask& src,
-                                      const SkMatrix& matrix, SkIPoint* margin) {
+                                      const SkMatrix& matrix,
+                                      SkIPoint* margin) const{
     SkScalar radius;
     if (fBlurFlags & SkBlurMaskFilter::kIgnoreTransform_BlurFlag) {
         radius = fRadius;
@@ -153,7 +154,7 @@
 SkBlurMaskFilterImpl::filterRectsToNine(const SkRect rects[], int count,
                                         const SkMatrix& matrix,
                                         const SkIRect& clipBounds,
-                                        NinePatch* patch) {
+                                        NinePatch* patch) const {
     if (count < 1 || count > 2) {
         return kUnimplemented_FilterReturn;
     }
@@ -249,7 +250,8 @@
     return kTrue_FilterReturn;
 }
 
-void SkBlurMaskFilterImpl::computeFastBounds(const SkRect& src, SkRect* dst) {
+void SkBlurMaskFilterImpl::computeFastBounds(const SkRect& src,
+                                             SkRect* dst) const {
     dst->set(src.fLeft - fRadius, src.fTop - fRadius,
              src.fRight + fRadius, src.fBottom + fRadius);
 }
diff --git a/src/effects/SkEmbossMaskFilter.cpp b/src/effects/SkEmbossMaskFilter.cpp
index 6480f50..0c91585 100644
--- a/src/effects/SkEmbossMaskFilter.cpp
+++ b/src/effects/SkEmbossMaskFilter.cpp
@@ -60,12 +60,12 @@
     normalize(fLight.fDirection);
 }
 
-SkMask::Format SkEmbossMaskFilter::getFormat() {
+SkMask::Format SkEmbossMaskFilter::getFormat() const {
     return SkMask::k3D_Format;
 }
 
 bool SkEmbossMaskFilter::filterMask(SkMask* dst, const SkMask& src,
-                                    const SkMatrix& matrix, SkIPoint* margin) {
+                            const SkMatrix& matrix, SkIPoint* margin) const {
     SkScalar radius = matrix.mapRadius(fBlurRadius);
 
     if (!SkBlurMask::Blur(dst, src, radius, SkBlurMask::kInner_Style,
diff --git a/src/effects/SkKernel33MaskFilter.cpp b/src/effects/SkKernel33MaskFilter.cpp
index 1568a4f..0f198cd 100644
--- a/src/effects/SkKernel33MaskFilter.cpp
+++ b/src/effects/SkKernel33MaskFilter.cpp
@@ -9,12 +9,12 @@
 #include "SkColorPriv.h"
 #include "SkFlattenableBuffers.h"
 
-SkMask::Format SkKernel33ProcMaskFilter::getFormat() {
+SkMask::Format SkKernel33ProcMaskFilter::getFormat() const {
     return SkMask::kA8_Format;
 }
 
 bool SkKernel33ProcMaskFilter::filterMask(SkMask* dst, const SkMask& src,
-                                          const SkMatrix&, SkIPoint* margin) {
+                                      const SkMatrix&, SkIPoint* margin) const {
     // margin???
     dst->fImage = NULL;
     dst->fBounds = src.fBounds;
@@ -86,7 +86,7 @@
 
 ///////////////////////////////////////////////////////////////////////////////
 
-uint8_t SkKernel33MaskFilter::computeValue(uint8_t* const* srcRows) {
+uint8_t SkKernel33MaskFilter::computeValue(uint8_t* const* srcRows) const {
     int value = 0;
 
     for (int i = 0; i < 3; i++) {
diff --git a/src/effects/SkStippleMaskFilter.cpp b/src/effects/SkStippleMaskFilter.cpp
index 434528e..24b9114 100644
--- a/src/effects/SkStippleMaskFilter.cpp
+++ b/src/effects/SkStippleMaskFilter.cpp
@@ -11,7 +11,7 @@
 bool SkStippleMaskFilter::filterMask(SkMask* dst,
                                      const SkMask& src,
                                      const SkMatrix& matrix,
-                                     SkIPoint* margin) {
+                                     SkIPoint* margin) const {
 
     if (src.fFormat != SkMask::kA8_Format) {
         return false;
diff --git a/src/effects/SkTableMaskFilter.cpp b/src/effects/SkTableMaskFilter.cpp
index d1fe134..73b7fa6 100644
--- a/src/effects/SkTableMaskFilter.cpp
+++ b/src/effects/SkTableMaskFilter.cpp
@@ -17,17 +17,13 @@
 }
 
 SkTableMaskFilter::SkTableMaskFilter(const uint8_t table[256]) {
-    this->setTable(table);
+    memcpy(fTable, table, sizeof(fTable));
 }
 
 SkTableMaskFilter::~SkTableMaskFilter() {}
 
-void SkTableMaskFilter::setTable(const uint8_t table[256]) {
-    memcpy(fTable, table, 256);
-}
-
 bool SkTableMaskFilter::filterMask(SkMask* dst, const SkMask& src,
-                                 const SkMatrix&, SkIPoint* margin) {
+                                 const SkMatrix&, SkIPoint* margin) const {
     if (src.fFormat != SkMask::kA8_Format) {
         return false;
     }
@@ -68,7 +64,7 @@
     return true;
 }
 
-SkMask::Format SkTableMaskFilter::getFormat() {
+SkMask::Format SkTableMaskFilter::getFormat() const {
     return SkMask::kA8_Format;
 }