Make all color xforms 'fast' (step 1)

src/core/SkColorSpaceXform.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 SkColorSpaceXform_DEFINED
 #define SkColorSpaceXform_DEFINED
 
@@ skipping 16 matching lines @@
     /**
      *  Apply the color conversion to a src buffer, storing the output in the dst buffer.
      *  The src is opaque and stored in RGBA_8888, and the dst is also opaque and stored
      *  in 8888 platform format.
      */
     virtual void xform_RGB1_8888(uint32_t* dst, const uint32_t* src, uint32_t len) const = 0;
 
     virtual ~SkColorSpaceXform() {}
 };
 
-template <SkColorSpace::GammaNamed Src, SkColorSpace::GammaNamed Dst>
+template <SkColorSpace::GammaNamed Dst>
 class SkFastXform : public SkColorSpaceXform {
 public:
 
     void xform_RGB1_8888(uint32_t* dst, const uint32_t* src, uint32_t len) const override;
 
 private:
-    SkFastXform(const SkMatrix44& srcToDst);
+    SkFastXform(const sk_sp<SkColorSpace>& srcSpace, const SkMatrix44& srcToDst,
+                const sk_sp<SkColorSpace>& dstSpace);
 
-    float fSrcToDst[12];
+    static constexpr int kDstGammaTableSize = 1024;
+
+    // May contain pointers into storage or pointers into precomputed tables.
+    const float*         fSrcGammaTables[3];
+    float                fSrcGammaTableStorage[3 * 256];
+
+    float                fSrcToDst[12];
+
+    // May contain pointers into storage or pointers into precomputed tables.
+    const uint8_t*       fDstGammaTables[3];
+    uint8_t              fDstGammaTableStorage[3 * kDstGammaTableSize];
 
     friend class SkColorSpaceXform;
 };
 
 /**
  *  Works for any valid src and dst profiles.
  */
 class SkDefaultXform : public SkColorSpaceXform {
 public:
 
@@ skipping 14 matching lines @@
     const SkMatrix44          fSrcToDst;
 
     // May contain pointers into storage or pointers into precomputed tables.
     const uint8_t*            fDstGammaTables[3];
     uint8_t                   fDstGammaTableStorage[3 * kDstGammaTableSize];
 
     friend class SkColorSpaceXform;
 };
 
 #endif