store 3 bits of luminance, but (for now) discretize that in fonthost::filterec

for backward compatibility



git-svn-id: http://skia.googlecode.com/svn/trunk@2732 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 33 insertions, 10 deletions

diff --git a/include/core/SkScalerContext.h b/include/core/SkScalerContext.h
index 9b3264087b..22c22270ee 100644
--- a/include/core/SkScalerContext.h
+++ b/include/core/SkScalerContext.h
@@ -164,23 +164,29 @@ public:
         kSubpixelPositioning_Flag = 0x0010,
         kAutohinting_Flag         = 0x0020,
         kVertical_Flag            = 0x0040,
+
         // together, these two flags resulting in a two bit value which matches
         // up with the SkPaint::Hinting enum.
+        kHinting_Shift            = 7, // to shift into the other flags above
         kHintingBit1_Flag         = 0x0080,
         kHintingBit2_Flag         = 0x0100,
+
         // these should only ever be set if fMaskFormat is LCD16 or LCD32
         kLCD_Vertical_Flag        = 0x0200,    // else Horizontal
         kLCD_BGROrder_Flag        = 0x0400,    // else RGB order
-        // gamma flags
-        kGammaForBlack_Flag       = 0x0800,
-        kGammaForWhite_Flag       = 0x1000,
+
+        // luminance : 0 for black text, kLuminance_Max for white text
+        kLuminance_Shift          = 11, // to shift into the other flags above
+        kLuminance_Bits           = 3,  // ensure Flags doesn't exceed 16bits
     };
-private:
+    
+    // computed values
     enum {
-        kHintingMask = kHintingBit1_Flag | kHintingBit2_Flag,
-        kHintingShift = 7
+        kHinting_Mask   = kHintingBit1_Flag | kHintingBit2_Flag,
+        kLuminance_Max  = (1 << kLuminance_Bits) - 1,
+        kLuminance_Mask = kLuminance_Max << kLuminance_Shift,
     };
-public:
+
     struct Rec {
         uint32_t    fOrigFontID;
         uint32_t    fFontID;
@@ -200,12 +206,29 @@ public:
         void    getSingleMatrix(SkMatrix*) const;
 
         SkPaint::Hinting getHinting() const {
-            unsigned hint = (fFlags & kHintingMask) >> kHintingShift;
+            unsigned hint = (fFlags & kHinting_Mask) >> kHinting_Shift;
             return static_cast<SkPaint::Hinting>(hint);
         }
 
         void setHinting(SkPaint::Hinting hinting) {
-            fFlags = (fFlags & ~kHintingMask) | (hinting << kHintingShift);
+            fFlags = (fFlags & ~kHinting_Mask) | (hinting << kHinting_Shift);
+        }
+
+        unsigned getLuminanceBits() const {
+            return (fFlags & kLuminance_Mask) >> kLuminance_Shift;
+        }
+        
+        void setLuminanceBits(unsigned lum) {
+            SkASSERT(lum <= kLuminance_Max);
+            fFlags = (fFlags & ~kLuminance_Mask) | (lum << kLuminance_Shift);
+        }
+
+        U8CPU getLuminanceByte() const {
+            SkASSERT(3 == kLuminance_Bits);
+            unsigned lum = this->getLuminanceBits();
+            lum |= (lum << kLuminance_Bits);
+            lum |= (lum << kLuminance_Bits*2);
+            return lum >> (4*kLuminance_Bits - 8);
         }
 
         SkMask::Format getFormat() const {
@@ -230,7 +253,7 @@ public:
         fact correspond to a different font/context. In that case, we use the
         base-glyph-count to know how to translate back into local glyph space.
      */
-    uint16_t    charToGlyphID(SkUnichar uni);
+    uint16_t charToGlyphID(SkUnichar uni);
 
     /** Map the glyphID to its glyph index, and then to its char code. Unmapped
         glyphs return zero.