Skia: bring us closer to upstream.

I want to bring us closer to upstream Skia. This patch consists of
hunks pulled from code.google.com/p/skia. I'll also be pushing changes
the other way.

Review URL: http://codereview.chromium.org/57018


git-svn-id: svn://svn.chromium.org/chrome/trunk/src@12873 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 12 insertions, 0 deletions

diff --git a/skia/include/SkScalerContext.h b/skia/include/SkScalerContext.h
index ec2cd0d..df846f2 100644
--- a/skia/include/SkScalerContext.h
+++ b/skia/include/SkScalerContext.h
@@ -85,6 +85,12 @@ struct SkGlyph {
     
     size_t computeImageSize() const;
     
+    /** Call this to set all of the metrics fields to 0 (e.g. if the scaler
+        encounters an error measuring a glyph). Note: this does not alter the
+        fImage, fPath, fID, fMaskFormat fields.
+     */
+    void zeroMetrics();
+
     enum {
         kSubBits = 2,
         kSubMask = ((1 << kSubBits) - 1),
@@ -163,10 +169,16 @@ public:
     SkScalerContext(const SkDescriptor* desc);
     virtual ~SkScalerContext();
 
+    // remember our glyph offset/base
     void setBaseGlyphCount(unsigned baseGlyphCount) {
         fBaseGlyphCount = baseGlyphCount;
     }
 
+    /** Return the corresponding glyph for the specified unichar. Since contexts
+        may be chained (under the hood), the glyphID that is returned may in
+        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);
 
     unsigned    getGlyphCount() const { return this->generateGlyphCount(); }