WIP -- SkFont

include/core/SkFont.h

+/*
+ * Copyright 2014 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+#include "SkRefCnt.h"
+#include "SkScalar.h"
+
+class SkPaint;
+class SkTypeface;
+
+enum SkTextEncoding {
+    kUTF8_SkTextEncoding,
+    kUTF16_SkTextEncoding,
+    kUTF32_SkTextEncoding,
+    kGlyphID_SkTextEncoding,
+};
+
+class SkFont : public SkRefCnt {
+public:
+    enum Flags {
+        /**
+         *  Use the system's automatic hinting mechanism to hint the typeface.
+         *  If both bytecode and auto hints are specified, attempt to use the bytecodes first.
+         *  If that fails (e.g. there are no codes), then attempt to autohint.
+         */
+        kEnableAutoHints_Flag       = 1 << 0,
+
+        /**
+         *  If the typeface contains explicit bytecodes for hinting, use them.
+         *  If both bytecode and auto hints are specified, attempt to use the bytecodes first;
+         *  if that fails (e.g. there are no codes), then attempt to autohint.
+         */
+        kEnableByteCodeHints_Flag   = 1 << 1,
+
+        /**
+         *  Use rounded metric values (e.g. advance).
+         *  If either auto or bytecode hinting was used, apply those results to the metrics of the
+         *  glyphs as well. If no hinting was applied, the metrics will just be rounded to the
+         *  nearest integer.
+         *
+         *  This applies to calls that return metrics (e.g. measureText) and to drawing the glyphs
+         *  (see SkCanvas drawText and drawPosText).
+         */
+        kUseNonlinearMetrics_Flag   = 1 << 2,
+
+        kVertical_Flag              = 1 << 3,
+        kEmbeddedBitmaps_Flag       = 1 << 4,
+        kGenA8FromLCD_Flag          = 1 << 5,
+        kEmbolden_Flag              = 1 << 6,
+    };
+
+    enum MaskType {
+        kBW_MaskType,
+        kA8_MaskType,
+        kLCD_MaskType,
+    };
+
+    SkTypeface* getTypeface() const { return fTypeface; }
+    SkScalar    getSize() const { return fSize; }
+    SkScalar    getScaleX() const { return fScaleX; }
+    SkScalar    getSkewX() const { return fSkewX; }
+    uint32_t    getFlags() const { return fFlags; }
+    MaskType    getMaskType() const {
+        return (MaskType)fMaskType;
+    }
+
+    int textToGlyphs(const void* text, size_t byteLength, SkTextEncoding,
+                     uint16_t glyphs[], int maxGlyphCount) const;
+
+    SkScalar measureText(const void* text, size_t byteLength, SkTextEncoding) const;
+
+    static SkFont* Create(SkTypeface*, SkScalar size, MaskType, uint32_t flags);
+    static SkFont* Create(SkTypeface*, SkScalar size, SkScalar scaleX, SkScalar skewX,
+                          MaskType, uint32_t flags);
+    static SkFont* Create(const SkFont&, SkScalar newSize);
+
+    static SkFont* Testing_CreateFromPaint(const SkPaint&);
+
+private:
+    enum {
+        kAllFlags = 0x3F,
+    };
+    
+    SkFont(SkTypeface*, SkScalar size, SkScalar scaleX, SkScalar skewX, MaskType, uint32_t flags);
+    virtual ~SkFont();
+
+    SkTypeface* fTypeface;
+    SkScalar    fSize;
+    SkScalar    fScaleX;
+    SkScalar    fSkewX;
+    uint16_t    fFlags;
+    uint8_t     fMaskType;
+    uint8_t     fPad;
+};
+