Revert "change SkColorTable to be immutable"

include/core/SkColorTable.h

 
 /*
  * Copyright 2012 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #ifndef SkColorTable_DEFINED
 #define SkColorTable_DEFINED
 
-#include "SkAlpha.h"
 #include "SkColor.h"
 #include "SkFlattenable.h"
 
 /** \class SkColorTable
 
     SkColorTable holds an array SkPMColors (premultiplied 32-bit colors) used by
     8-bit bitmaps, where the bitmap bytes are interpreted as indices into the colortable.
 */
 class SkColorTable : public SkFlattenable {
 public:
     SK_DECLARE_INST_COUNT(SkColorTable)
 
     /** Makes a deep copy of colors.
      */
     SkColorTable(const SkColorTable& src);
-    SkColorTable(const SkPMColor colors[], int count,
-                 SkAlphaType alphaType = kPremul_SkAlphaType);
+    /** Preallocates the colortable to have 'count' colors, which
+     *  are initially set to 0.
+    */
+    explicit SkColorTable(int count);
+    SkColorTable(const SkPMColor colors[], int count);
     virtual ~SkColorTable();
 
-    SkAlphaType alphaType() const { return (SkAlphaType)fAlphaType; }
+    enum Flags {
+        kColorsAreOpaque_Flag   = 0x01  //!< if set, all of the colors in the table are opaque (alpha==0xFF)
+    };
+    /** Returns the flag bits for the color table. These can be changed with setFlags().
+    */
+    unsigned getFlags() const { return fFlags; }
+    /** Set the flags for the color table. See the Flags enum for possible values.
+    */
+    void    setFlags(unsigned flags);
 
-    bool isOpaque() const {
-        return SkAlphaTypeIsOpaque(this->alphaType());
-    }
+    bool isOpaque() const { return (fFlags & kColorsAreOpaque_Flag) != 0; }
+    void setIsOpaque(bool isOpaque);
 
     /** Returns the number of colors in the table.
     */
     int count() const { return fCount; }
 
     /** Returns the specified color from the table. In the debug build, this asserts that
         the index is in range (0 <= index < count).
     */
     SkPMColor operator[](int index) const {
         SkASSERT(fColors != NULL && (unsigned)index < fCount);
         return fColors[index];
     }
 
-    /**
-     *  Return the array of colors for reading. This must be balanced by a call
-     *  to unlockColors().
-     */
-    const SkPMColor* lockColors() {
+    /** Specify the number of colors in the color table. This does not initialize the colors
+        to any value, just allocates memory for them. To initialize the values, either call
+        setColors(array, count), or follow setCount(count) with a call to
+        lockColors()/{set the values}/unlockColors(true).
+    */
+//    void    setColors(int count) { this->setColors(NULL, count); }
+//    void    setColors(const SkPMColor[], int count);
+
+    /** Return the array of colors for reading and/or writing. This must be
+        balanced by a call to unlockColors(changed?), telling the colortable if
+        the colors were changed during the lock.
+    */
+    SkPMColor* lockColors() {
         SkDEBUGCODE(sk_atomic_inc(&fColorLockCount);)
         return fColors;
     }
-
-    /**
-     *  Balancing call to lockColors().
-     */
-    void unlockColors();
+    /** Balancing call to lockColors(). If the colors have been changed, pass true.
+    */
+    void unlockColors(bool changed);
 
     /** Similar to lockColors(), lock16BitCache() returns the array of
         RGB16 colors that mirror the 32bit colors. However, this function
         will return null if kColorsAreOpaque_Flag is not set.
         Also, unlike lockColors(), the returned array here cannot be modified.
     */
     const uint16_t* lock16BitCache();
     /** Balancing call to lock16BitCache().
     */
     void unlock16BitCache() {
         SkASSERT(f16BitCacheLockCount > 0);
         SkDEBUGCODE(f16BitCacheLockCount -= 1);
     }
 
     SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkColorTable)
 
 protected:
     explicit SkColorTable(SkFlattenableReadBuffer&);
     void flatten(SkFlattenableWriteBuffer&) const;
 
 private:
     SkPMColor*  fColors;
     uint16_t*   f16BitCache;
     uint16_t    fCount;
-    uint8_t     fAlphaType;
+    uint8_t     fFlags;
     SkDEBUGCODE(int fColorLockCount;)
     SkDEBUGCODE(int f16BitCacheLockCount;)
 
     void inval16BitCache();
 
     typedef SkFlattenable INHERITED;
 };
 
 #endif