bluecore/ftgl/FTFont.h
2008-01-16 11:45:17 +00:00

277 lines
8.0 KiB
C++

#ifndef __FTFont__
#define __FTFont__
#include <ft2build.h>
#include FT_FREETYPE_H
#include "FTFace.h"
#include "FTGL.h"
class FTGlyphContainer;
class FTGlyph;
/**
* FTFont is the public interface for the FTGL library.
*
* Specific font classes are derived from this class. It uses the helper
* classes FTFace and FTSize to access the Freetype library. This class
* is abstract and deriving classes must implement the protected
* <code>MakeGlyph</code> function to create glyphs of the
* appropriate type.
*
* It is good practice after using these functions to test the error
* code returned. <code>FT_Error Error()</code>. Check the freetype file fterrdef.h
* for error definitions.
*
* @see FTFace
* @see FTSize
* @see FTGlyphContainer
* @see FTGlyph
*/
class FTGL_EXPORT FTFont
{
public:
/**
* Open and read a font file. Sets Error flag.
*
* @param fontFilePath font file path.
*/
FTFont( const char* fontFilePath);
/**
* Open and read a font from a buffer in memory. Sets Error flag.
* The buffer is owned by the client and is NOT copied by FTGL. The
* pointer must be valid while using FTGL.
*
* @param pBufferBytes the in-memory buffer
* @param bufferSizeInBytes the length of the buffer in bytes
*/
FTFont( const unsigned char *pBufferBytes, size_t bufferSizeInBytes);
/**
* Destructor
*/
virtual ~FTFont();
/**
* Attach auxilliary file to font e.g font metrics.
*
* Note: not all font formats implement this function.
*
* @param fontFilePath auxilliary font file path.
* @return <code>true</code> if file has been attached
* successfully.
*/
bool Attach( const char* fontFilePath);
/**
* Attach auxilliary data to font e.g font metrics, from memory
*
* Note: not all font formats implement this function.
*
* @param pBufferBytes the in-memory buffer
* @param bufferSizeInBytes the length of the buffer in bytes
* @return <code>true</code> if file has been attached
* successfully.
*/
bool Attach( const unsigned char *pBufferBytes, size_t bufferSizeInBytes);
/**
* Set the character map for the face.
*
* @param encoding Freetype enumerate for char map code.
* @return <code>true</code> if charmap was valid and
* set correctly
*/
bool CharMap( FT_Encoding encoding );
/**
* Get the number of character maps in this face.
*
* @return character map count.
*/
unsigned int CharMapCount();
/**
* Get a list of character maps in this face.
*
* @return pointer to the first encoding.
*/
FT_Encoding* CharMapList();
/**
* Set the char size for the current face.
*
* @param size the face size in points (1/72 inch)
* @param res the resolution of the target device.
* @return <code>true</code> if size was set correctly
*/
virtual bool FaceSize( const unsigned int size, const unsigned int res = 72);
/**
* Get the current face size in points.
*
* @return face size
*/
unsigned int FaceSize() const;
/**
* Set the extrusion distance for the font. Only implemented by
* FTGLExtrdFont
*
* @param depth The extrusion distance.
*/
virtual void Depth( float depth){}
/**
* Enable or disable the use of Display Lists inside FTGL
*
* @param useList <code>true</code> turns ON display lists.
* <code>false</code> turns OFF display lists.
*/
void UseDisplayList( bool useList);
/**
* Get the global ascender height for the face.
*
* @return Ascender height
*/
float Ascender() const;
/**
* Gets the global descender height for the face.
*
* @return Descender height
*/
float Descender() const;
/**
* Gets the line spacing for the font.
*
* @return Line height
*/
float LineHeight() const;
/**
* Get the bounding box for a string.
*
* @param string a char string
* @param llx lower left near x coord
* @param lly lower left near y coord
* @param llz lower left near z coord
* @param urx upper right far x coord
* @param ury upper right far y coord
* @param urz upper right far z coord
*/
void BBox( const char* string, float& llx, float& lly, float& llz, float& urx, float& ury, float& urz);
/**
* Get the bounding box for a string.
*
* @param string a wchar_t string
* @param llx lower left near x coord
* @param lly lower left near y coord
* @param llz lower left near z coord
* @param urx upper right far x coord
* @param ury upper right far y coord
* @param urz upper right far z coord
*/
void BBox( const wchar_t* string, float& llx, float& lly, float& llz, float& urx, float& ury, float& urz);
/**
* Get the advance width for a string.
*
* @param string a wchar_t string
* @return advance width
*/
float Advance( const wchar_t* string);
/**
* Get the advance width for a string.
*
* @param string a char string
* @return advance width
*/
float Advance( const char* string);
/**
* Render a string of characters
*
* @param string 'C' style string to be output.
*/
virtual void Render( const char* string );
/**
* Render a string of characters
*
* @param string wchar_t string to be output.
*/
virtual void Render( const wchar_t* string );
/**
* Queries the Font for errors.
*
* @return The current error code.
*/
FT_Error Error() const { return err;}
protected:
/**
* Construct a glyph of the correct type.
*
* Clients must overide the function and return their specialised
* FTGlyph.
*
* @param g The glyph index NOT the char code.
* @return An FT****Glyph or <code>null</code> on failure.
*/
virtual FTGlyph* MakeGlyph( unsigned int g) = 0;
/**
* Current face object
*/
FTFace face;
/**
* Current size object
*/
FTSize charSize;
/**
* Flag to enable or disable the use of Display Lists inside FTGL
* <code>true</code> turns ON display lists.
* <code>false</code> turns OFF display lists.
*/
bool useDisplayLists;
/**
* Current error code. Zero means no error.
*/
FT_Error err;
private:
/**
* Check that the glyph at <code>chr</code> exist. If not load it.
*
* @param chr character index
* @return <code>true</code> if the glyph can be created.
*/
inline bool CheckGlyph( const unsigned int chr);
/**
* An object that holds a list of glyphs
*/
FTGlyphContainer* glyphList;
/**
* Current pen or cursor position;
*/
FTPoint pen;
};
#endif // __FTFont__