xref: /external/webkit/Source/WebCore/platform/graphics/chromium/FontPlatformDataLinux.h

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#ifndef FontPlatformDataLinux_h
#define FontPlatformDataLinux_h

#include "FontOrientation.h"
#include "FontRenderStyle.h"
#include "TextOrientation.h"
#include <wtf/Forward.h>
#include <wtf/RefPtr.h>
#include <wtf/text/CString.h>
#include <wtf/text/StringImpl.h>
#include <SkPaint.h>

class SkTypeface;
typedef uint32_t SkFontID;

struct HB_FaceRec_;

namespace WebCore {

class FontDescription;

// -----------------------------------------------------------------------------
// FontPlatformData is the handle which WebKit has on a specific face. A face
// is the tuple of (font, size, ...etc). Here we are just wrapping a Skia
// SkTypeface pointer and dealing with the reference counting etc.
// -----------------------------------------------------------------------------
class FontPlatformData {
public:
    // Used for deleted values in the font cache's hash tables. The hash table
    // will create us with this structure, and it will compare other values
    // to this "Deleted" one. It expects the Deleted one to be differentiable
    // from the NULL one (created with the empty constructor), so we can't just
    // set everything to NULL.
    FontPlatformData(WTF::HashTableDeletedValueType)
        : m_typeface(hashTableDeletedFontValue())
        , m_textSize(0)
        , m_emSizeInFontUnits(0)
        , m_fakeBold(false)
        , m_fakeItalic(false)
        , m_orientation(Horizontal)
        , m_textOrientation(TextOrientationVerticalRight)
        { }

    FontPlatformData()
        : m_typeface(0)
        , m_textSize(0)
        , m_emSizeInFontUnits(0)
        , m_fakeBold(false)
        , m_fakeItalic(false)
        , m_orientation(Horizontal)
        , m_textOrientation(TextOrientationVerticalRight)
        { }

    FontPlatformData(float textSize, bool fakeBold, bool fakeItalic)
        : m_typeface(0)
        , m_textSize(textSize)
        , m_emSizeInFontUnits(0)
        , m_fakeBold(fakeBold)
        , m_fakeItalic(fakeItalic)
        , m_orientation(Horizontal)
        , m_textOrientation(TextOrientationVerticalRight)
        { }

    FontPlatformData(const FontPlatformData&);
    FontPlatformData(SkTypeface*, const char* name, float textSize, bool fakeBold, bool fakeItalic, FontOrientation = Horizontal, TextOrientation = TextOrientationVerticalRight);
    FontPlatformData(const FontPlatformData& src, float textSize);
    ~FontPlatformData();

    // -------------------------------------------------------------------------
    // Return true iff this font is monospaced (i.e. every glyph has an equal x
    // advance)
    // -------------------------------------------------------------------------
    bool isFixedPitch() const;

    // -------------------------------------------------------------------------
    // Setup a Skia painting context to use this font.
    // -------------------------------------------------------------------------
    void setupPaint(SkPaint*) const;

    // -------------------------------------------------------------------------
    // Return Skia's unique id for this font. This encodes both the style and
    // the font's file name so refers to a single face.
    // -------------------------------------------------------------------------
    SkFontID uniqueID() const;

    unsigned hash() const;
    float size() const { return m_textSize; }
    int emSizeInFontUnits() const;

    FontOrientation orientation() const { return m_orientation; }
    void setOrientation(FontOrientation orientation) { m_orientation = orientation; }

    bool operator==(const FontPlatformData&) const;
    FontPlatformData& operator=(const FontPlatformData&);
    bool isHashTableDeletedValue() const { return m_typeface == hashTableDeletedFontValue(); }

#ifndef NDEBUG
    String description() const;
#endif

    HB_FaceRec_* harfbuzzFace() const;

    // -------------------------------------------------------------------------
    // Global font preferences...

    static void setHinting(SkPaint::Hinting);
    static void setAntiAlias(bool on);
    static void setSubpixelGlyphs(bool on);

private:
    class RefCountedHarfbuzzFace : public RefCounted<RefCountedHarfbuzzFace> {
    public:
        static PassRefPtr<RefCountedHarfbuzzFace> create(HB_FaceRec_* harfbuzzFace)
        {
            return adoptRef(new RefCountedHarfbuzzFace(harfbuzzFace));
        }

        ~RefCountedHarfbuzzFace();

        HB_FaceRec_* face() const { return m_harfbuzzFace; }

    private:
        RefCountedHarfbuzzFace(HB_FaceRec_* harfbuzzFace) : m_harfbuzzFace(harfbuzzFace)
        {
        }

        HB_FaceRec_* m_harfbuzzFace;
    };

    void querySystemForRenderStyle();

    // FIXME: Could SkAutoUnref be used here?
    SkTypeface* m_typeface;
    CString m_family;
    float m_textSize;
    mutable int m_emSizeInFontUnits;
    bool m_fakeBold;
    bool m_fakeItalic;
    FontOrientation m_orientation;
    TextOrientation m_textOrientation;
    FontRenderStyle m_style;
    mutable RefPtr<RefCountedHarfbuzzFace> m_harfbuzzFace;

    SkTypeface* hashTableDeletedFontValue() const { return reinterpret_cast<SkTypeface*>(-1); }
};

}  // namespace WebCore

#endif  // ifdef FontPlatformData_h