path: root/converter/other/pamtosvg/curve.c

/* curve.c: operations on the lists of pixels and lists of curves.

   The code was partially derived from limn.

   Copyright (C) 1992 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.  */

#include "mallocvar.h"

#include "logreport.h"
#include "curve.h"


static float_coord
int_to_real_coord(pm_pixelcoord const int_coord) {
/*----------------------------------------------------------------------------
  Turn an integer point into a real one.
-----------------------------------------------------------------------------*/
    float_coord real_coord;

    real_coord.x = int_coord.col;
    real_coord.y = int_coord.row;
    real_coord.z = 0.0;
    
    return real_coord;
}



/* Return an entirely empty curve.  */

curve *
new_curve(void) {
  curve * curveP;

  MALLOCVAR_NOFAIL(curveP);

  curveP->point_list = NULL;
  CURVE_LENGTH(curveP) = 0;
  CURVE_CYCLIC(curveP) = false;
  PREVIOUS_CURVE(curveP)  = NULL;
  NEXT_CURVE(curveP)      = NULL;

  return curveP;
}


/* Don't copy the points or tangents, but copy everything else.  */

curve_type
copy_most_of_curve (curve_type old_curve)
{
  curve_type curve = new_curve ();

  CURVE_CYCLIC (curve) = CURVE_CYCLIC (old_curve);
  PREVIOUS_CURVE (curve) = PREVIOUS_CURVE (old_curve);
  NEXT_CURVE (curve) = NEXT_CURVE (old_curve);

  return curve;
}

void
move_curve(curve * const dstP,
           curve * const srcP) {

    /* Move ownership of dynamically allocated memory from source 
       to destination; destroy source.
    */

   if (CURVE_LENGTH(dstP) > 0)
       free(dstP->point_list);
    
   *dstP = *srcP;

   free(srcP);
}



/* The length of CURVE will be zero if we ended up not being able to fit
   it (which in turn implies a problem elsewhere in the program, but at
   any rate, we shouldn't try here to free the nonexistent curve).  */

void
free_curve(curve * const curveP) {

   if (CURVE_LENGTH(curveP) > 0)
       free(curveP->point_list);

   free(curveP);
}



void
append_point(curve_type  const curve,
             float_coord const coord) {

    CURVE_LENGTH(curve)++;
    REALLOCARRAY_NOFAIL(curve->point_list, CURVE_LENGTH(curve));
    LAST_CURVE_POINT(curve) = coord;
    /* The t value does not need to be set.  */
}


void
append_pixel(curve_type    const curve,
             pm_pixelcoord const coord) {

    append_point(curve, int_to_real_coord(coord));
}


/* Print a curve in human-readable form.  It turns out we never care
   about most of the points on the curve, and so it is pointless to
   print them all out umpteen times.  What matters is that we have some
   from the end and some from the beginning.  */

#define NUM_TO_PRINT 3

#define LOG_CURVE_POINT(c, p, print_t)					\
  do									\
    {									\
      LOG2 ("(%.3f,%.3f)", CURVE_POINT (c, p).x, CURVE_POINT (c, p).y);	\
      if (print_t)							\
        LOG1 ("/%.2f", CURVE_T (c, p));					\
    }									\
  while (0)



void
log_curve(curve * const curveP,
          bool    const print_t) {

    if (!log_file)
        return;

    LOG1("curve id = %lx:\n", (unsigned long) curveP);
    LOG1("  length = %u.\n", CURVE_LENGTH(curveP));
    if (CURVE_CYCLIC(curveP))
        LOG("  cyclic.\n");

    LOG("  ");

    /* If the curve is short enough, don't use ellipses.  */
    if (CURVE_LENGTH(curveP) <= NUM_TO_PRINT * 2) {
        unsigned int thisPoint;
    
        for (thisPoint = 0; thisPoint < CURVE_LENGTH(curveP); ++thisPoint) {
            LOG_CURVE_POINT(curveP, thisPoint, print_t);
            LOG(" ");

            if (thisPoint != CURVE_LENGTH(curveP) - 1
                && (thisPoint + 1) % NUM_TO_PRINT == 0)
                LOG("\n  ");
        }
    } else {
        unsigned int thisPoint;
        for (thisPoint = 0;
             thisPoint < NUM_TO_PRINT && thisPoint < CURVE_LENGTH(curveP);
             ++thisPoint) {
            LOG_CURVE_POINT(curveP, thisPoint, print_t);
            LOG(" ");
        }

        LOG("...\n   ...");

        for (thisPoint = CURVE_LENGTH(curveP) - NUM_TO_PRINT;
             thisPoint < CURVE_LENGTH(curveP);
             ++thisPoint) {
            LOG(" ");
            LOG_CURVE_POINT(curveP, thisPoint, print_t);
        }
    }
    LOG(".\n");
}


/* Like `log_curve', but write the whole thing.  */

void
log_entire_curve(curve * const curveP) {

    unsigned int thisPoint;

    if (!log_file)
        return;

    LOG1("curve id = %lx:\n", (unsigned long) curveP);
    LOG1("  length = %u.\n", CURVE_LENGTH(curveP));
    if (CURVE_CYCLIC(curveP))
        LOG("  cyclic.\n");

    LOG(" ");

    for (thisPoint = 0; thisPoint < CURVE_LENGTH(curveP); ++thisPoint) {
        LOG(" ");
        LOG_CURVE_POINT(curveP, thisPoint, true);
        /* Compiler warning `Condition is always true' can be ignored */
    }

    LOG(".\n");
}



/* Return an initialized but empty curve list.  */

curve_list_type
new_curve_list (void)
{
  curve_list_type curve_list;

  curve_list.length = 0;
  curve_list.data = NULL;

  return curve_list;
}


/* Free a curve list and all the curves it contains.  */

void
free_curve_list(curve_list_type * const curveListP) {

    unsigned int thisCurve;

    for (thisCurve = 0; thisCurve < curveListP->length; ++thisCurve)
        free_curve(curveListP->data[thisCurve]);

    /* If the character was empty, it won't have any curves.  */
    if (curveListP->data != NULL)
        free (curveListP->data);
}


/* Add an element to a curve list.  */

void
append_curve (curve_list_type *curve_list, curve_type curve)
{
  curve_list->length++;
  REALLOCARRAY_NOFAIL(curve_list->data, curve_list->length);
  curve_list->data[curve_list->length - 1] = curve; }


/* Return an initialized but empty curve list array.  */

curve_list_array_type
new_curve_list_array (void)
{
  curve_list_array_type curve_list_array;

  CURVE_LIST_ARRAY_LENGTH (curve_list_array) = 0;
  curve_list_array.data = NULL;

  return curve_list_array;
}


/* Free a curve list array and all the curve lists it contains.  */

void
free_curve_list_array(const curve_list_array_type * const curve_list_array,
                      at_progress_func                    notify_progress, 
                      void *                        const client_data) {

  unsigned this_list;

  for (this_list = 0; this_list < CURVE_LIST_ARRAY_LENGTH(*curve_list_array);
       this_list++) {
      if (notify_progress)
          notify_progress(((float)this_list)/
                          (CURVE_LIST_ARRAY_LENGTH(*curve_list_array) *
                           (float)3.0)+(float)0.666 ,
                          client_data);
      free_curve_list(&CURVE_LIST_ARRAY_ELT (*curve_list_array, this_list));
  }
  
  /* If the character was empty, it won't have any curves.  */
  if (curve_list_array->data != NULL)
      free(curve_list_array->data);
}


/* Add an element to a curve list array.  */

void
append_curve_list(curve_list_array_type * const curve_list_array,
                  curve_list_type         const curve_list) {

  CURVE_LIST_ARRAY_LENGTH (*curve_list_array)++;
  REALLOCARRAY_NOFAIL(curve_list_array->data,
                      CURVE_LIST_ARRAY_LENGTH(*curve_list_array));
  LAST_CURVE_LIST_ARRAY_ELT (*curve_list_array) = curve_list;
}