ref: c49f69cb8c9d9b38179f760bf0cbbe4c78a3e296
dir: /src/autohint/ahoptim.h/
/***************************************************************************/
/* */
/* FreeType Auto-Gridder Outline Optimisation */
/* */
/* This module is in charge of optimising the outlines produced by the */
/* auto-hinter in direct mode. This is required at small pixel sizes in */
/* order to ensure coherent spacing, among other things.. */
/* */
/* The technique used in this module is a simplified simulated annealing. */
/* */
/* Copyright 2000: Catharon Productions Inc. */
/* Author: David Turner */
/* */
/* This file is part of the Catharon Typography Project and shall only */
/* be used, modified, and distributed under the terms of the Catharon */
/* Open Source License that should come with this file under the name */
/* "CatharonLicense.txt". By continuing to use, modify, or distribute */
/* this file you indicate that you have read the license and */
/* understand and accept it fully. */
/* */
/* Note that this license is compatible with the FreeType license */
/* */
/***************************************************************************/
#ifndef AGOPTIM_H
#define AGOPTIM_H
#ifdef FT_FLAT_COMPILE
#include "ahtypes.h"
#else
#include <autohint/ahtypes.h>
#endif
/* the maximal number of stem configurations to record during optimisation */
#define AH_MAX_CONFIGS 8
typedef struct AH_Stem_
{
FT_Pos pos; /* current position */
FT_Pos velocity; /* current velocity */
FT_Pos force; /* sum of current forces */
FT_Pos width; /* normalized width */
FT_Pos min_pos; /* minimum grid position */
FT_Pos max_pos; /* maximum grid position */
AH_Edge* edge1; /* left/bottom edge */
AH_Edge* edge2; /* right/top edge */
FT_Pos opos; /* original position */
FT_Pos owidth; /* original width */
FT_Pos min_coord; /* minimum coordinate */
FT_Pos max_coord; /* maximum coordinate */
} AH_Stem;
/* A spring between two stems */
typedef struct AH_Spring_
{
AH_Stem* stem1;
AH_Stem* stem2;
FT_Pos owidth; /* original width */
FT_Pos tension; /* current tension */
} AH_Spring;
/* A configuration records the position of each stem at a given time */
/* as well as the associated distortion.. */
typedef struct AH_Configuration_
{
FT_Pos* positions;
FT_Long distorsion;
} AH_Configuration;
typedef struct AH_Optimizer_
{
FT_Memory memory;
AH_Outline* outline;
FT_Int num_hstems;
AH_Stem* horz_stems;
FT_Int num_vstems;
AH_Stem* vert_stems;
FT_Int num_hsprings;
FT_Int num_vsprings;
AH_Spring* horz_springs;
AH_Spring* vert_springs;
FT_Int num_configs;
AH_Configuration configs[ AH_MAX_CONFIGS ];
FT_Pos* positions;
/* during each pass, use these instead */
FT_Int num_stems;
AH_Stem* stems;
FT_Int num_springs;
AH_Spring* springs;
FT_Bool vertical;
FT_Fixed tension_scale;
FT_Pos tension_threshold;
} AH_Optimizer;
/* loads the outline into the optimizer */
extern
int AH_Optimizer_Init( AH_Optimizer* optimizer,
AH_Outline* outline,
FT_Memory memory );
/* compute optimal outline */
extern
void AH_Optimizer_Compute( AH_Optimizer* optimizer );
/* releases the optimisation data */
extern
void AH_Optimizer_Done( AH_Optimizer* optimizer );
#endif /* AGOPTIM_H */