experiment: float color components

include/core/SkShader.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 SkShader_DEFINED
 #define SkShader_DEFINED
 
@@ skipping 63 matching lines @@
     enum Flags {
         //!< set if all of the colors will be opaque
         kOpaqueAlpha_Flag = 1 << 0,
 
         /** set if the spans only vary in X (const in Y).
             e.g. an Nx1 bitmap that is being tiled in Y, or a linear-gradient
             that varies from left-to-right. This flag specifies this for
             shadeSpan().
          */
         kConstInY32_Flag = 1 << 1,
+        kSupports4f_Flag = 1 << 2,
     };
 
     /**
      *  Returns true if the shader is guaranteed to produce only opaque
      *  colors, subject to the SkPaint using the shader to apply an opaque
      *  alpha value. Subclasses should override this to allow some
      *  optimizations.
      */
     virtual bool isOpaque() const { return false; }
 
@@ skipping 26 matching lines @@
          */
         virtual uint32_t getFlags() const { return 0; }
 
         /**
          *  Called for each span of the object being drawn. Your subclass should
          *  set the appropriate colors (with premultiplied alpha) that correspond
          *  to the specified device coordinates.
          */
         virtual void shadeSpan(int x, int y, SkPMColor[], int count) = 0;
 
+        virtual void shadeSpan4f(int x, int y, SkPM4f[], int count);
+
         /**
          * The const void* ctx is only const because all the implementations are const.
          * This can be changed to non-const if a new shade proc needs to change the ctx.
          */
         typedef void (*ShadeProc)(const void* ctx, int x, int y, SkPMColor[], int count);
         virtual ShadeProc asAShadeProc(void** ctx);
 
         /**
          *  Similar to shadeSpan, but only returns the alpha-channel for a span.
          *  The default implementation calls shadeSpan() and then extracts the alpha
@@ skipping 184 matching lines @@
      *  Call this to create a new "empty" shader, that will not draw anything.
      */
     static SkShader* CreateEmptyShader();
 
     /**
      *  Call this to create a new shader that just draws the specified color. This should always
      *  draw the same as a paint with this color (and no shader).
      */
     static SkShader* CreateColorShader(SkColor);
 
+    static SkShader* CreateColorShader(const SkColor4f&);
+
     /** Call this to create a new shader that will draw with the specified bitmap.
      *
      *  If the bitmap cannot be used (e.g. has no pixels, or its dimensions
      *  exceed implementation limits (currently at 64K - 1)) then SkEmptyShader
      *  may be returned.
      *
      *  If the src is kA8_Config then that mask will be colorized using the color on
      *  the paint.
      *
      *  @param src  The bitmap to use inside the shader
@@ skipping 63 matching lines @@
     SkMatrix fLocalMatrix;
 
     // So the SkLocalMatrixShader can whack fLocalMatrix in its SkReadBuffer constructor.
     friend class SkLocalMatrixShader;
     friend class SkBitmapProcShader;    // for computeTotalInverse()
 
     typedef SkFlattenable INHERITED;
 };
 
 #endif