ICU 57.1: LEFontInstance.h Source File

00001 
00002 /*
00003  *
00004  * (C) Copyright IBM Corp. 1998-2015 - All Rights Reserved
00005  *
00006  */
00007 
00008 #ifndef __LEFONTINSTANCE_H
00009 #define __LEFONTINSTANCE_H
00010 
00011 #include "LETypes.h"
00017 U_NAMESPACE_BEGIN
00018 
00028 class LECharMapper /* not : public UObject because this is an interface/mixin class */
00029 {
00030 public:
00035     virtual ~LECharMapper();
00036 
00046     virtual LEUnicode32 mapChar(LEUnicode32 ch) const = 0;
00047 };
00048 
00055 class LEGlyphStorage;
00056 
00081 class U_LAYOUT_API LEFontInstance : public UObject
00082 {
00083 public:
00084 
00091     virtual ~LEFontInstance();
00092 
00144     virtual const LEFontInstance *getSubFont(const LEUnicode chars[], le_int32 *offset, le_int32 limit, le_int32 script, LEErrorCode &success) const;
00145 
00146     //
00147     // Font file access
00148     //
00149 
00165     virtual const void* getFontTable(LETag tableTag, size_t &length) const = 0;
00166 
00183     virtual le_bool canDisplay(LEUnicode32 ch) const;
00184 
00193     virtual le_int32 getUnitsPerEM() const = 0;
00194 
00218     virtual void mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, const LECharMapper *mapper, le_bool filterZeroWidth, LEGlyphStorage &glyphStorage) const;
00219 
00235     virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper, le_bool filterZeroWidth) const;
00236 
00251     virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper) const;
00252 
00265     virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch) const = 0;
00266 
00267     //
00268     // Metrics
00269     //
00270 
00279     virtual void getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const = 0;
00280 
00293     virtual le_bool getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const = 0;
00294 
00303     virtual float getXPixelsPerEm() const = 0;
00304 
00313     virtual float getYPixelsPerEm() const = 0;
00314 
00325     virtual float xUnitsToPoints(float xUnits) const;
00326 
00337     virtual float yUnitsToPoints(float yUnits) const;
00338 
00347     virtual void unitsToPoints(LEPoint &units, LEPoint &points) const;
00348 
00359     virtual float xPixelsToUnits(float xPixels) const;
00360 
00371     virtual float yPixelsToUnits(float yPixels) const;
00372 
00381     virtual void pixelsToUnits(LEPoint &pixels, LEPoint &units) const;
00382 
00394     virtual float getScaleFactorX() const = 0;
00395 
00406     virtual float getScaleFactorY() const = 0;
00407 
00423     virtual void transformFunits(float xFunits, float yFunits, LEPoint &pixels) const;
00424 
00435     static inline float fixedToFloat(le_int32 fixed);
00436 
00447     static inline le_int32 floatToFixed(float theFloat);
00448 
00449     //
00450     // These methods won't ever be called by the LayoutEngine,
00451     // but are useful for clients of <code>LEFontInstance</code> who
00452     // need to render text.
00453     //
00454 
00463     virtual le_int32 getAscent() const = 0;
00464 
00473     virtual le_int32 getDescent() const = 0;
00474 
00483     virtual le_int32 getLeading() const = 0;
00484 
00495     virtual le_int32 getLineHeight() const;
00496 
00502     virtual UClassID getDynamicClassID() const;
00503 
00509     static UClassID getStaticClassID();
00510 
00511 };
00512 
00513 inline float LEFontInstance::fixedToFloat(le_int32 fixed)
00514 {
00515     return (float) (fixed / 65536.0);
00516 }
00517 
00518 inline le_int32 LEFontInstance::floatToFixed(float theFloat)
00519 {
00520     return (le_int32) (theFloat * 65536.0);
00521 }
00522 
00523 U_NAMESPACE_END
00524 #endif