+++ /dev/null
-/* Libart_LGPL - library of basic graphic primitives
- * Copyright (C) 1998-2000 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.
- */
-
-/* "Unsort" a sorted vector path into an ordinary vector path. */
-
-#include <stdio.h> /* for printf - debugging */
-#include "art_misc.h"
-
-#include "art_vpath.h"
-#include "art_svp.h"
-#include "art_vpath_svp.h"
-
-typedef struct _ArtVpathSVPEnd ArtVpathSVPEnd;
-
-struct _ArtVpathSVPEnd {
- int seg_num;
- int which; /* 0 = top, 1 = bottom */
- double x, y;
-};
-
-#define EPSILON 1e-6
-
-static int
-art_vpath_svp_point_compare (double x1, double y1, double x2, double y2)
-{
- if (y1 - EPSILON > y2) return 1;
- if (y1 + EPSILON < y2) return -1;
- if (x1 - EPSILON > x2) return 1;
- if (x1 + EPSILON < x2) return -1;
- return 0;
-}
-
-static int
-art_vpath_svp_compare (const void *s1, const void *s2)
-{
- const ArtVpathSVPEnd *e1 = s1;
- const ArtVpathSVPEnd *e2 = s2;
-
- return art_vpath_svp_point_compare (e1->x, e1->y, e2->x, e2->y);
-}
-
-/* Convert from sorted vector path representation into regular
- vector path representation.
-
- Status of this routine:
-
- Basic correctness: Only works with closed paths.
-
- Numerical stability: Not known to work when more than two segments
- meet at a point.
-
- Speed: Should be pretty good.
-
- Precision: Does not degrade precision.
-
-*/
-/**
- * art_vpath_from_svp: Convert from svp to vpath form.
- * @svp: Original #ArtSVP.
- *
- * Converts the sorted vector path @svp into standard vpath form.
- *
- * Return value: the newly allocated vpath.
- **/
-ArtVpath *
-art_vpath_from_svp (const ArtSVP *svp)
-{
- int n_segs = svp->n_segs;
- ArtVpathSVPEnd *ends;
- ArtVpath *new;
- int *visited;
- int n_new, n_new_max;
- int i, k;
- int j = 0; /* Quiet compiler */
- int seg_num;
- int first;
- double last_x, last_y;
- int n_points;
- int pt_num;
-
- last_x = 0; /* to eliminate "uninitialized" warning */
- last_y = 0;
-
- ends = art_new (ArtVpathSVPEnd, n_segs * 2);
- for (i = 0; i < svp->n_segs; i++)
- {
- int lastpt;
-
- ends[i * 2].seg_num = i;
- ends[i * 2].which = 0;
- ends[i * 2].x = svp->segs[i].points[0].x;
- ends[i * 2].y = svp->segs[i].points[0].y;
-
- lastpt = svp->segs[i].n_points - 1;
- ends[i * 2 + 1].seg_num = i;
- ends[i * 2 + 1].which = 1;
- ends[i * 2 + 1].x = svp->segs[i].points[lastpt].x;
- ends[i * 2 + 1].y = svp->segs[i].points[lastpt].y;
- }
- qsort (ends, n_segs * 2, sizeof (ArtVpathSVPEnd), art_vpath_svp_compare);
-
- n_new = 0;
- n_new_max = 16; /* I suppose we _could_ estimate this from traversing
- the svp, so we don't have to reallocate */
- new = art_new (ArtVpath, n_new_max);
-
- visited = art_new (int, n_segs);
- for (i = 0; i < n_segs; i++)
- visited[i] = 0;
-
- first = 1;
- for (i = 0; i < n_segs; i++)
- {
- if (!first)
- {
- /* search for the continuation of the existing subpath */
- /* This could be a binary search (which is why we sorted, above) */
- for (j = 0; j < n_segs * 2; j++)
- {
- if (!visited[ends[j].seg_num] &&
- art_vpath_svp_point_compare (last_x, last_y,
- ends[j].x, ends[j].y) == 0)
- break;
- }
- if (j == n_segs * 2)
- first = 1;
- }
- if (first)
- {
- /* start a new subpath */
- for (j = 0; j < n_segs * 2; j++)
- if (!visited[ends[j].seg_num])
- break;
- }
- if (j == n_segs * 2)
- {
- printf ("failure\n");
- }
- seg_num = ends[j].seg_num;
- n_points = svp->segs[seg_num].n_points;
- for (k = 0; k < n_points; k++)
- {
- pt_num = svp->segs[seg_num].dir ? k : n_points - (1 + k);
- if (k == 0)
- {
- if (first)
- {
- art_vpath_add_point (&new, &n_new, &n_new_max,
- ART_MOVETO,
- svp->segs[seg_num].points[pt_num].x,
- svp->segs[seg_num].points[pt_num].y);
- }
- }
- else
- {
- art_vpath_add_point (&new, &n_new, &n_new_max,
- ART_LINETO,
- svp->segs[seg_num].points[pt_num].x,
- svp->segs[seg_num].points[pt_num].y);
- if (k == n_points - 1)
- {
- last_x = svp->segs[seg_num].points[pt_num].x;
- last_y = svp->segs[seg_num].points[pt_num].y;
- /* to make more robust, check for meeting first_[xy],
- set first if so */
- }
- }
- first = 0;
- }
- visited[seg_num] = 1;
- }
-
- art_vpath_add_point (&new, &n_new, &n_new_max,
- ART_END, 0, 0);
- art_free (visited);
- art_free (ends);
- return new;
-}
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