зеркало из https://github.com/mozilla/pjs.git
153 строки
4.3 KiB
C
153 строки
4.3 KiB
C
/* Libart_LGPL - library of basic graphic primitives
|
|
* Copyright (C) 1998 Raph Levien
|
|
*
|
|
* This library is free software; you can redistribute it and/or
|
|
* modify it under the terms of the GNU Library General Public
|
|
* License as published by the Free Software Foundation; either
|
|
* version 2 of the License, or (at your option) any later version.
|
|
*
|
|
* This library 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
|
|
* Library General Public License for more details.
|
|
*
|
|
* You should have received a copy of the GNU Library General Public
|
|
* License along with this library; if not, write to the
|
|
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
|
|
* Boston, MA 02111-1307, USA.
|
|
*/
|
|
|
|
/* Basic constructors and operations for sorted vector paths */
|
|
|
|
#include "config.h"
|
|
#include "art_svp.h"
|
|
|
|
#include "art_misc.h"
|
|
|
|
/* Add a new segment. The arguments can be zero and NULL if the caller
|
|
would rather fill them in later.
|
|
|
|
We also realloc one auxiliary array of ints of size n_segs if
|
|
desired.
|
|
*/
|
|
/**
|
|
* art_svp_add_segment: Add a segment to an #ArtSVP structure.
|
|
* @p_vp: Pointer to where the #ArtSVP structure is stored.
|
|
* @pn_segs_max: Pointer to the allocated size of *@p_vp.
|
|
* @pn_points_max: Pointer to where auxiliary array is stored.
|
|
* @n_points: Number of points for new segment.
|
|
* @dir: Direction for new segment; 0 is up, 1 is down.
|
|
* @points: Points for new segment.
|
|
* @bbox: Bounding box for new segment.
|
|
*
|
|
* Adds a new segment to an ArtSVP structure. This routine reallocates
|
|
* the structure if necessary, updating *@p_vp and *@pn_segs_max as
|
|
* necessary.
|
|
*
|
|
* The new segment is simply added after all other segments. Thus,
|
|
* this routine should be called in order consistent with the #ArtSVP
|
|
* sorting rules.
|
|
*
|
|
* If the @bbox argument is given, it is simply stored in the new
|
|
* segment. Otherwise (if it is NULL), the bounding box is computed
|
|
* from the @points given.
|
|
**/
|
|
int
|
|
art_svp_add_segment (ArtSVP **p_vp, int *pn_segs_max,
|
|
int **pn_points_max,
|
|
int n_points, int dir, ArtPoint *points,
|
|
ArtDRect *bbox)
|
|
{
|
|
int seg_num;
|
|
ArtSVP *svp;
|
|
ArtSVPSeg *seg;
|
|
|
|
svp = *p_vp;
|
|
seg_num = svp->n_segs++;
|
|
if (*pn_segs_max == seg_num)
|
|
{
|
|
*pn_segs_max <<= 1;
|
|
svp = (ArtSVP *)art_realloc (svp, sizeof(ArtSVP) +
|
|
(*pn_segs_max - 1) * sizeof(ArtSVPSeg));
|
|
*p_vp = svp;
|
|
if (pn_points_max != NULL)
|
|
*pn_points_max = art_renew (*pn_points_max, int, *pn_segs_max);
|
|
}
|
|
seg = &svp->segs[seg_num];
|
|
seg->n_points = n_points;
|
|
seg->dir = dir;
|
|
seg->points = points;
|
|
if (bbox)
|
|
seg->bbox = *bbox;
|
|
else if (points)
|
|
{
|
|
double x_min, x_max;
|
|
int i;
|
|
|
|
x_min = x_max = points[0].x;
|
|
for (i = 1; i < n_points; i++)
|
|
{
|
|
if (x_min > points[i].x)
|
|
x_min = points[i].x;
|
|
if (x_max < points[i].x)
|
|
x_max = points[i].x;
|
|
}
|
|
seg->bbox.x0 = x_min;
|
|
seg->bbox.y0 = points[0].y;
|
|
|
|
seg->bbox.x1 = x_max;
|
|
seg->bbox.y1 = points[n_points - 1].y;
|
|
}
|
|
return seg_num;
|
|
}
|
|
|
|
|
|
/**
|
|
* art_svp_free: Free an #ArtSVP structure.
|
|
* @svp: #ArtSVP to free.
|
|
*
|
|
* Frees an #ArtSVP structure and all the segments in it.
|
|
**/
|
|
void
|
|
art_svp_free (ArtSVP *svp)
|
|
{
|
|
int n_segs = svp->n_segs;
|
|
int i;
|
|
|
|
for (i = 0; i < n_segs; i++)
|
|
art_free (svp->segs[i].points);
|
|
art_free (svp);
|
|
}
|
|
|
|
#ifdef ART_USE_NEW_INTERSECTOR
|
|
#define EPSILON 0
|
|
#else
|
|
#define EPSILON 1e-6
|
|
#endif
|
|
|
|
/**
|
|
* art_svp_seg_compare: Compare two segments of an svp.
|
|
* @seg1: First segment to compare.
|
|
* @seg2: Second segment to compare.
|
|
*
|
|
* Compares two segments of an svp. Return 1 if @seg2 is below or to the
|
|
* right of @seg1, -1 otherwise.
|
|
**/
|
|
int
|
|
art_svp_seg_compare (const void *s1, const void *s2)
|
|
{
|
|
const ArtSVPSeg *seg1 = s1;
|
|
const ArtSVPSeg *seg2 = s2;
|
|
|
|
if (seg1->points[0].y - EPSILON > seg2->points[0].y) return 1;
|
|
else if (seg1->points[0].y + EPSILON < seg2->points[0].y) return -1;
|
|
else if (seg1->points[0].x - EPSILON > seg2->points[0].x) return 1;
|
|
else if (seg1->points[0].x + EPSILON < seg2->points[0].x) return -1;
|
|
else if ((seg1->points[1].x - seg1->points[0].x) *
|
|
(seg2->points[1].y - seg2->points[0].y) -
|
|
(seg1->points[1].y - seg1->points[0].y) *
|
|
(seg2->points[1].x - seg2->points[0].x) > 0) return 1;
|
|
else return -1;
|
|
}
|
|
|