ICU 57.1 57.1
LEFontInstance.h
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1
2/*
3 *
4 * (C) Copyright IBM Corp. 1998-2015 - All Rights Reserved
5 *
6 */
7
8#ifndef __LEFONTINSTANCE_H
9#define __LEFONTINSTANCE_H
10
11#include "LETypes.h"
18
28class LECharMapper /* not : public UObject because this is an interface/mixin class */
29{
30public:
35 virtual ~LECharMapper();
36
46 virtual LEUnicode32 mapChar(LEUnicode32 ch) const = 0;
47};
48
55class LEGlyphStorage;
56
82{
83public:
84
91 virtual ~LEFontInstance();
92
144 virtual const LEFontInstance *getSubFont(const LEUnicode chars[], le_int32 *offset, le_int32 limit, le_int32 script, LEErrorCode &success) const;
145
146 //
147 // Font file access
148 //
149
165 virtual const void* getFontTable(LETag tableTag, size_t &length) const = 0;
166
183 virtual le_bool canDisplay(LEUnicode32 ch) const;
184
193 virtual le_int32 getUnitsPerEM() const = 0;
194
218 virtual void mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, const LECharMapper *mapper, le_bool filterZeroWidth, LEGlyphStorage &glyphStorage) const;
219
235 virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper, le_bool filterZeroWidth) const;
236
251 virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper) const;
252
265 virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch) const = 0;
266
267 //
268 // Metrics
269 //
270
279 virtual void getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const = 0;
280
293 virtual le_bool getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const = 0;
294
303 virtual float getXPixelsPerEm() const = 0;
304
313 virtual float getYPixelsPerEm() const = 0;
314
325 virtual float xUnitsToPoints(float xUnits) const;
326
337 virtual float yUnitsToPoints(float yUnits) const;
338
347 virtual void unitsToPoints(LEPoint &units, LEPoint &points) const;
348
359 virtual float xPixelsToUnits(float xPixels) const;
360
371 virtual float yPixelsToUnits(float yPixels) const;
372
381 virtual void pixelsToUnits(LEPoint &pixels, LEPoint &units) const;
382
394 virtual float getScaleFactorX() const = 0;
395
406 virtual float getScaleFactorY() const = 0;
407
423 virtual void transformFunits(float xFunits, float yFunits, LEPoint &pixels) const;
424
435 static inline float fixedToFloat(le_int32 fixed);
436
447 static inline le_int32 floatToFixed(float theFloat);
448
449 //
450 // These methods won't ever be called by the LayoutEngine,
451 // but are useful for clients of <code>LEFontInstance</code> who
452 // need to render text.
453 //
454
463 virtual le_int32 getAscent() const = 0;
464
473 virtual le_int32 getDescent() const = 0;
474
483 virtual le_int32 getLeading() const = 0;
484
495 virtual le_int32 getLineHeight() const;
496
503
510
511};
512
514{
515 return (float) (fixed / 65536.0);
516}
517
519{
520 return (le_int32) (theFloat * 65536.0);
521}
522
524#endif
C API: Basic definitions for the ICU LayoutEngine.
UChar32 LEUnicode32
Used to represent 32-bit Unicode code points.
Definition: LETypes.h:230
LEErrorCode
Error codes returned by the LayoutEngine.
Definition: LETypes.h:687
int32_t le_int32
A type used for signed, 32-bit integers.
Definition: LETypes.h:34
UBool le_bool
A type used for boolean values.
Definition: LETypes.h:77
UChar LEUnicode
Used to represent 16-bit Unicode code points.
Definition: LETypes.h:238
le_uint32 LETag
Used for four character tags.
Definition: LETypes.h:93
le_uint32 LEGlyphID
Used for glyph indices.
Definition: LETypes.h:112
Instances of this class are used by LEFontInstance::mapCharsToGlyphs and LEFontInstance::mapCharToGly...
virtual LEUnicode32 mapChar(LEUnicode32 ch) const =0
This method does the adjustments.
virtual ~LECharMapper()
Destructor.
This is a virtual base class that serves as the interface between a LayoutEngine and the platform fon...
virtual float xPixelsToUnits(float xPixels) const
This method converts pixels in the X direction to font design units.
virtual float xUnitsToPoints(float xUnits) const
This method converts font design units in the X direction to points.
static UClassID getStaticClassID()
ICU "poor man's RTTI", returns a UClassID for this class.
virtual void unitsToPoints(LEPoint &units, LEPoint &points) const
This method converts font design units to points.
virtual float getYPixelsPerEm() const =0
This method returns the height of the font's EM square in pixels.
virtual void getGlyphAdvance(LEGlyphID glyph, LEPoint &advance) const =0
This method gets the X and Y advance of a particular glyph, in pixels.
virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper, le_bool filterZeroWidth) const
This method maps a single character to a glyph index, using the font's character to glyph map.
virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch) const =0
This method maps a single character to a glyph index, using the font's character to glyph map.
virtual float yUnitsToPoints(float yUnits) const
This method converts font design units in the Y direction to points.
static le_int32 floatToFixed(float theFloat)
This is a convenience method used to convert floating point values to 16.16 fixed point format.
virtual float getXPixelsPerEm() const =0
This method returns the width of the font's EM square in pixels.
virtual le_int32 getUnitsPerEM() const =0
This method returns the number of design units in the font's EM square.
virtual float getScaleFactorX() const =0
Get the X scale factor from the font's transform.
virtual float getScaleFactorY() const =0
Get the Y scale factor from the font's transform.
virtual le_int32 getDescent() const =0
Get the font's descent.
virtual LEGlyphID mapCharToGlyph(LEUnicode32 ch, const LECharMapper *mapper) const
This method maps a single character to a glyph index, using the font's character to glyph map.
virtual le_int32 getLineHeight() const
Get the line height required to display text in this font.
virtual le_bool canDisplay(LEUnicode32 ch) const
This method is used to determine if the font can render the given character.
virtual void pixelsToUnits(LEPoint &pixels, LEPoint &units) const
This method converts pixels to font design units.
virtual void mapCharsToGlyphs(const LEUnicode chars[], le_int32 offset, le_int32 count, le_bool reverse, const LECharMapper *mapper, le_bool filterZeroWidth, LEGlyphStorage &glyphStorage) const
This method maps an array of character codes to an array of glyph indices, using the font's character...
virtual float yPixelsToUnits(float yPixels) const
This method converts pixels in the Y direction to font design units.
virtual le_int32 getLeading() const =0
Get the font's leading.
virtual UClassID getDynamicClassID() const
ICU "poor man's RTTI", returns a UClassID for the actual class.
virtual le_bool getGlyphPoint(LEGlyphID glyph, le_int32 pointNumber, LEPoint &point) const =0
This method gets the hinted X and Y pixel coordinates of a particular point in the outline of the giv...
static float fixedToFloat(le_int32 fixed)
This is a convenience method used to convert values in a 16.16 fixed point format to floating point.
virtual const LEFontInstance * getSubFont(const LEUnicode chars[], le_int32 *offset, le_int32 limit, le_int32 script, LEErrorCode &success) const
Get a physical font which can render the given text.
virtual le_int32 getAscent() const =0
Get the font's ascent.
virtual const void * getFontTable(LETag tableTag, size_t &length) const =0
This method reads a table from the font.
virtual void transformFunits(float xFunits, float yFunits, LEPoint &pixels) const
This method transforms an X, Y point in font design units to a pixel coordinate, applying the font's ...
virtual ~LEFontInstance()
This virtual destructor is here so that the subclass destructors can be invoked through the base clas...
This class encapsulates the per-glyph storage used by the ICU LayoutEngine.
UObject is the common ICU "boilerplate" class.
Definition: uobject.h:221
Used to hold a pair of (x, y) values which represent a point.
Definition: LETypes.h:247
void * UClassID
UClassID is used to identify classes without using the compiler's RTTI.
Definition: uobject.h:91
#define U_LAYOUT_API
Set to export library symbols from inside the layout engine library, and to import them from outside.
Definition: utypes.h:359
#define U_NAMESPACE_END
This is used to end a declaration of a public ICU C++ API.
Definition: uversion.h:130
#define U_NAMESPACE_BEGIN
This is used to begin a declaration of a public ICU C++ API.
Definition: uversion.h:129