Cache dst LUTs in SkColorSpaceXform

src/core/SkColorSpace_Base.h

 /*
  * Copyright 2016 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #ifndef SkColorSpace_Base_DEFINED
 #define SkColorSpace_Base_DEFINED
 
@@ skipping 159 matching lines @@
 class SkColorSpace_Base : public SkColorSpace {
 public:
     SkGammaNamed gammaNamed() const { return fGammaNamed; }
     const SkGammas* gammas() const { return fGammas.get(); }
 
     const SkColorLookUpTable* colorLUT() const { return fColorLUT.get(); }
 
     const SkMatrix44& toXYZD50() const { return fToXYZD50; }
     const SkMatrix44& fromXYZD50() const;
     
+    void toDstGammaTables(const uint8_t* tables[3], sk_sp<SkData>* storage, int numTables) const;
+
     /**
      *  Create an SkColorSpace with the same gamut as this color space, but with linear gamma.
      */
     sk_sp<SkColorSpace> makeLinearGamma();
 
 private:
 
     /**
      *  FIXME (msarett):
      *  Hiding this function until we can determine if we need it.  Known issues include:
      *  Only writes 3x3 matrices
      *  Only writes float gammas
      *  Rejected by some parsers because the "profile description" is empty
      */
     sk_sp<SkData> writeToICC() const;
 
     static sk_sp<SkColorSpace> NewRGB(SkGammaNamed gammaNamed, const SkMatrix44& toXYZD50);
 
     SkColorSpace_Base(SkGammaNamed gammaNamed, const SkMatrix44& toXYZ);
 
     SkColorSpace_Base(sk_sp<SkColorLookUpTable> colorLUT, SkGammaNamed gammaNamed,
                       sk_sp<SkGammas> gammas, const SkMatrix44& toXYZ, sk_sp<SkData> profileData);
 
-    sk_sp<SkColorLookUpTable> fColorLUT;
-    const SkGammaNamed        fGammaNamed;
-    sk_sp<SkGammas>           fGammas;
-    sk_sp<SkData>             fProfileData;
+    sk_sp<SkColorLookUpTable>      fColorLUT;
+    const SkGammaNamed             fGammaNamed;
+    sk_sp<SkGammas>                fGammas;
+    sk_sp<SkData>                  fProfileData;
 
-    const SkMatrix44          fToXYZD50;
-    mutable SkMatrix44        fFromXYZD50;
-    mutable SkOnce            fFromXYZOnce;
+    const SkMatrix44               fToXYZD50;
+    mutable SkMatrix44             fFromXYZD50;
+    mutable SkOnce                 fFromXYZOnce;
+
+    mutable sk_sp<SkData>          fDstStorage;
+    mutable const uint8_t*         fToDstGammaTables[3];
+    mutable SkOnce                 fToDstGammaOnce;
 
     friend class SkColorSpace;
     friend class ColorSpaceXformTest;
     friend class ColorSpaceTest;
     typedef SkColorSpace INHERITED;
 };
 
 static inline SkColorSpace_Base* as_CSB(SkColorSpace* colorSpace) {
     return static_cast<SkColorSpace_Base*>(colorSpace);
 }
 
 static inline const SkColorSpace_Base* as_CSB(const SkColorSpace* colorSpace) {
     return static_cast<const SkColorSpace_Base*>(colorSpace);
 }
 
 static inline SkColorSpace_Base* as_CSB(const sk_sp<SkColorSpace>& colorSpace) {
     return static_cast<SkColorSpace_Base*>(colorSpace.get());
 }
 
 #endif