lcd blits for sRGB

include/core/SkXfermode.h

 
 /*
  * Copyright 2006 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkXfermode_DEFINED
@@ skipping 230 matching lines @@
         const SkXfermode* fXfer;
         uint32_t          fFlags;
     };
     typedef void (*U64Proc1)(const U64State&, uint64_t dst[], const SkPM4f& src, int count,
                              const SkAlpha coverage[]);
     typedef void (*U64ProcN)(const U64State&, uint64_t dst[], const SkPM4f src[], int count,
                              const SkAlpha coverage[]);
     static U64Proc1 GetU64Proc1(Mode, uint32_t flags);
     static U64ProcN GetU64ProcN(Mode, uint32_t flags);
 
+    enum LCD32Flags {
+        kSrcIsOpaque_LCDFlag    = 1 << 0,
+        kSrcIsSingle_LCDFlag    = 1 << 1,
+        kDstIsLinearInt_LCDFlag = 1 << 2,   // srgb or float

[mtklein, 2016/02/18 13:35:55]

LinearInt  // srgb or float?

What's Int mean here?  Maybe just kDstIsLinear?

[reed1, 2016/02/18 15:11:35]

Yea, incomplete comment. fixed.

[f(malita), 2016/02/18 15:37:14]

I take it "Int" here stands for interpolation?  kDstIsLinear_LCDFlag seems less
confusing to me too.

+    };
+    typedef void (*LCD32Proc)(uint32_t* dst, const SkPM4f* src, int count, const uint16_t lcd[]);
+    typedef void (*LCD64Proc)(uint64_t* dst, const SkPM4f* src, int count, const uint16_t lcd[]);
+    static LCD32Proc GetLCD32Proc(uint32_t flags);
+    static LCD64Proc GetLCD64Proc(uint32_t) { return nullptr; }
+
 protected:
     SkXfermode() {}
     /** The default implementation of xfer32/xfer16/xferA8 in turn call this
         method, 1 color at a time (upscaled to a SkPMColor). The default
         implementation of this method just returns dst. If performance is
         important, your subclass should override xfer32/xfer16/xferA8 directly.
 
         This method will not be called directly by the client, so it need not
         be implemented if your subclass has overridden xfer32/xfer16/xferA8
     */
     virtual SkPMColor xferColor(SkPMColor src, SkPMColor dst) const;
 
 private:
     enum {
         kModeCount = kLastMode + 1
     };
 
     typedef SkFlattenable INHERITED;
 };
 
 #endif