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#include <freetype/internal/ftobjs.h>
#include <freetype/internal/ftdebug.h>
#include <freetype/internal/ftmemory.h>
#include <freetype/fttrigon.h>
#include "ftsdf.h"
#include "ftsdferrs.h"
#include "ftsdfcommon.h"
/**************************************************************************
*
* useful macros
*
*/
#define ONE 65536 /* 1 in 16.16 */
/**************************************************************************
*
* structs
*
*/
/**************************************************************************
*
* @Struct:
* BSDF_TRaster
*
* @Description:
* This struct is used in place of `FT_Raster' and is stored within
* the internal freetype renderer struct. While rasterizing this is
* passed to the `FT_Raster_Render_Func' function, which then can be
* used however we want.
*
* @Fields:
* memory ::
* Used internally to allocate intermediate memory while raterizing.
*
*/
typedef struct BSDF_TRaster_
{
FT_Memory memory;
} BSDF_TRaster;
/**************************************************************************
*
* @Struct:
* ED
*
* @Description:
* Euclidean distance used for euclidean distance transform can also be
* interpreted as edge distance.
*
* @Fields:
* dist ::
* Vector length of the `near' parameter. Can be squared or absolute
* depending on the `USE_SQUARED_DISTANCES' parameter defined in
* `ftsdfcommon.h'.
*
* near ::
* Vector to the nearest edge. Can also be interpreted as shortest
* distance of a point.
*
* alpha ::
* Alpha value of the original bitmap from which we generate SDF.
* While computing the gradient and determining the proper sign
* of a pixel this field is used.
*
*/
typedef struct ED_
{
FT_16D16 dist;
FT_16D16_Vec near;
FT_Byte alpha;
} ED;
/**************************************************************************
*
* @Struct:
* BSDF_Worker
*
* @Description:
* Just a convenient struct which is passed to most of the functions
* while generating SDF. This makes it easier to pass parameters because
* most functions require the same parameters.
*
* @Fields:
* distance_map ::
* A 1D array which is interpreted as 2D array. This array contains
* the Euclidean distance of all the points of the bitmap.
*
* width ::
* Width of the above `distance_map'.
*
* rows ::
* Number of rows in the above `distance_map'.
*
* params ::
* Internal params and properties required by the rasterizer. See
* `ftsdf.h' for the fields of this struct.
*
*/
typedef struct BSDF_Worker_
{
ED* distance_map;
FT_Int width;
FT_Int rows;
SDF_Raster_Params params;
} BSDF_Worker;
/**************************************************************************
*
* initializer
*
*/
static
const ED zero_ed = { 0, { 0, 0 }, 0 };
/* END */
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