SkiaFontWin.h   [plain text]


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#ifndef SkiaFontWin_h
#define SkiaFontWin_h

#include <windows.h>
#include <usp10.h>

struct SkPoint;

namespace WebCore {

class FontPlatformData;
class GraphicsContext;
class PlatformContextSkia;

#if !USE(SKIA_TEXT)
// The functions below are used for more complex font drawing (effects such as
// stroking and more complex transforms) than Windows supports directly. Since
// Windows drawing is faster you should use windowsCanHandleTextDrawing first to
// check if using Skia is required at all.
// Note that the text will look different (no ClearType) so this should only be
// used when necessary.
//
// When you call a Skia* text drawing function, various glyph outlines will be
// cached. As a result, you should call SkiaWinOutlineCache::removePathsForFont
// when the font is destroyed so that the cache does not outlive the font (since
// the HFONTs are recycled).
//
// Remember that Skia's text drawing origin is the baseline, like WebKit, not
// the top, like Windows.

// Returns true if the fillColor and shadowColor are opaque and the text-shadow
// is not blurred.
bool windowsCanHandleDrawTextShadow(GraphicsContext*);

// Returns true if advanced font rendering is recommended.
bool windowsCanHandleTextDrawing(GraphicsContext*);

// Returns true if advanced font rendering is recommended if shadows are
// disregarded.
bool windowsCanHandleTextDrawingWithoutShadow(GraphicsContext*);
#endif

// Note that the offsets parameter is optional. If not null it represents a
// per glyph offset (such as returned by ScriptPlace Windows API function).
void paintSkiaText(GraphicsContext*,
                   const FontPlatformData&,
                   int numGlyphs,
                   const WORD* glyphs,
                   const int* advances,
                   const GOFFSET* offsets,
                   const SkPoint* origin);

// Note that the offsets parameter is optional. If not null it represents a
// per glyph offset (such as returned by ScriptPlace Windows API function).
// Note: this is less efficient than calling the version with FontPlatformData,
// as that caches the SkTypeface object.
void paintSkiaText(GraphicsContext*,
                   HFONT,
                   int numGlyphs,
                   const WORD* glyphs,
                   const int* advances,
                   const GOFFSET* offsets,
                   const SkPoint* origin);

}  // namespace WebCore

#endif  // SkiaFontWin_h