ref: edfc0f8ac43e012d90e312bd7060630b8fa3d687
dir: /src/type1/t1driver.c/
/*******************************************************************
*
* t1driver.c
*
* High-level Type1 driver interface for FreeType 2.0
*
* Copyright 1996-1998 by
* David Turner, Robert Wilhelm, and Werner Lemberg.
*
* This file is part of the FreeType project, and may only be used,
* modified, and distributed under the terms of the FreeType project
* license, LICENSE.TXT. By continuing to use, modify, or distribute
* this file you indicate that you have read the license and
* understand and accept it fully.
*
******************************************************************/
#include <t1driver.h>
#include <t1gload.h>
#include <ftdebug.h>
#include <ftstream.h>
#undef FT_COMPONENT
#define FT_COMPONENT trace_t1driver
/******************************************************************/
/* */
/* <Function> Set_Char_Sizes */
/* */
/* <Description> */
/* A driver method used to reset a size's character sizes */
/* (horizontal and vertical) expressed in fractional points. */
/* */
/* <Input> */
/* size :: handle to target size object */
/* char_width :: character width expressed in 26.6 points */
/* char_height :: character height expressed in 26.6 points */
/* */
/* <Return> */
/* FreeType error code. 0 means success */
/* */
static
T1_Error Set_Char_Sizes( T1_Size size,
T1_F26Dot6 char_width,
T1_F26Dot6 char_height,
T1_UInt horz_resolution,
T1_UInt vert_resolution )
{
FT_Size_Metrics* metrics;
T1_Face face;
if (!size)
return T1_Err_Invalid_Size_Handle;
if ( char_width < 1*64 ) char_width = 1*64;
if ( char_height < 1*64 ) char_height = 1*64;
metrics = &size->root.metrics;
face = (T1_Face)size->root.face;
metrics->x_ppem = ( char_width * horz_resolution + 36 )/72;
metrics->y_ppem = ( char_height * vert_resolution + 36 )/72;
metrics->x_ppem = ( metrics->x_ppem + 32 ) & -64;
metrics->y_ppem = ( metrics->y_ppem + 32 ) & -64;
metrics->x_scale = FT_MulDiv( metrics->x_ppem, 0x10000,
face->root.units_per_EM );
metrics->y_scale = FT_MulDiv( metrics->y_ppem, 0x10000,
face->root.units_per_EM );
metrics->x_ppem >>= 6;
metrics->y_ppem >>= 6;
size->valid = FALSE;
return T1_Reset_Size( size );
}
/******************************************************************/
/* */
/* <Function> Set_Pixel_Sizes */
/* */
/* <Description> */
/* A driver method used to reset a size's character sizes */
/* (horizontal and vertical) expressed in integer pixels. */
/* */
/* <Input> */
/* size :: handle to target size object */
/* */
/* pixel_width :: character width expressed in 26.6 points */
/* */
/* pixel_height :: character height expressed in 26.6 points */
/* */
/* char_size :: the corresponding character size in points */
/* This value is only sent to the TrueType */
/* bytecode interpreter, even though 99% of */
/* glyph programs will simply ignore it. A */
/* safe value there is the maximum of the */
/* pixel width and height (multiplied by */
/* 64 to make it a 26.6 fixed float !) */
/* <Return> */
/* FreeType error code. 0 means success */
/* */
static
T1_Error Set_Pixel_Sizes( T1_Size size,
T1_Int pixel_width,
T1_Int pixel_height )
{
FT_Size_Metrics* metrics;
T1_Face face;
if (!size)
return T1_Err_Invalid_Size_Handle;
if ( pixel_width < 1 ) pixel_width = 1;
if ( pixel_height < 1 ) pixel_height = 1;
metrics = &size->root.metrics;
face = (T1_Face)size->root.face;
metrics->x_ppem = pixel_width;
metrics->y_ppem = pixel_height;
metrics->x_scale = FT_MulDiv( metrics->x_ppem * 64,
0x10000, face->root.units_per_EM );
metrics->y_scale = FT_MulDiv( metrics->y_ppem * 64,
0x10000, face->root.units_per_EM );
size->valid = 0;
return T1_Reset_Size(size);
}
/******************************************************************/
/* */
/* <Struct> FT_DriverInterface */
/* */
/* <Description> */
/* A structure used to hold a font driver's basic interface */
/* used by the high-level parts of FreeType (or other apps) */
/* */
/* Most scalable drivers provide a specialized interface to */
/* access format-specific features. It can be retrieved with */
/* a call to the "get_format_interface", and should be defined */
/* in each font driver header (e.g. ttdriver.h, t1driver.h,..) */
/* */
/* All fields are function pointers .. */
/* */
/* */
/* <Fields> */
/* */
/* new_engine :: */
/* used to create and initialise a new driver object */
/* */
/* done_engine :: */
/* used to finalise and destroy a given driver object */
/* */
/* get_format_interface :: */
/* return a typeless pointer to the format-specific */
/* driver interface. */
/* */
/* new_face :: */
/* create a new face object from a resource */
/* */
/* done_face :: */
/* discards a face object, as well as all child objects */
/* ( sizes, charmaps, glyph slots ) */
/* */
/* get_face_properties :: */
/* return generic face properties */
/* */
/* get_kerning :: */
/* return the kerning vector corresponding to a pair */
/* of glyphs, expressed in unscaled font units. */
/* */
/* new_size :: */
/* create and initialise a new scalable size object. */
/* */
/* new_fixed_size :: */
/* create and initialise a new fixed-size object. */
/* */
/* done_size :: */
/* finalize a given face size object. */
/* */
/* set_size_resolutions :: */
/* reset a scalable size object's output resolutions */
/* */
/* set_size_char_sizes :: */
/* reset a scalable size object's character size */
/* */
/* set_pixel_sizes :: */
/* reset a face size object's pixel dimensions. Applies */
/* to both scalable and fixed faces. */
/* */
/* new_glyph_slot :: */
/* create and initialise a new glyph slot */
/* */
/* done_glyph_slot :: */
/* discard a given glyph slot */
/* */
/* load_glyph :: */
/* load a given glyph into a given slot */
/* */
/* get_glyph_metrics :: */
/* return a loaded glyph's metrics. */
/* */
EXPORT_FUNC
const FT_DriverInterface t1_driver_interface =
{
sizeof( FT_DriverRec ),
sizeof( T1_FaceRec ),
sizeof( T1_SizeRec ),
sizeof( T1_GlyphSlotRec ),
"type1",
1,
2,
0, /* format interface */
(FTDriver_initDriver) T1_Init_Driver,
(FTDriver_doneDriver) T1_Done_Driver,
(FTDriver_getInterface) 0,
(FTDriver_initFace) T1_Init_Face,
(FTDriver_doneFace) T1_Done_Face,
(FTDriver_getKerning) 0,
(FTDriver_initSize) T1_Init_Size,
(FTDriver_doneSize) T1_Done_Size,
(FTDriver_setCharSizes) Set_Char_Sizes,
(FTDriver_setPixelSizes) Set_Pixel_Sizes,
(FTDriver_initGlyphSlot) T1_Init_GlyphSlot,
(FTDriver_doneGlyphSlot) T1_Done_GlyphSlot,
(FTDriver_loadGlyph) T1_Load_Glyph,
(FTDriver_getCharIndex) 0,
};
/******************************************************************/
/* */
/* <Function> Get_FreeType_Driver_Interface */
/* */
/* <Description> */
/* This function is used when compiling the TrueType driver */
/* as a shared library (.DLL or .so). It will be used by the */
/* high-level library of FreeType to retrieve the address of */
/* the driver's generic interface. */
/* */
/* It shouldn't be implemented in a static build, as each */
/* driver must have the same function as an exported entry */
/* point. */
/* */
/* <Return> */
/* address of TrueType's driver generic interface. The */
/* forma-specific interface can then be retrieved through */
/* the method interface->get_format_interface.. */
/* */
#ifdef FT_CONFIG_OPTION_DYNAMIC_DRIVERS
EXPORT_FUNC
FT_DriverInterface* getDriverInterface( void )
{
return &t1_driver_interface;
}
#endif /* FT_CONFIG_OPTION_DYNAMIC_DRIVERS */