--- /dev/null
+/*
+ Route simplification filter
+
+ Copyright (C) 2002 Robert Lipe, robertlipe@usa.net
+
+ 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 of the License, 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., 59 Temple Place - Suite 330, Boston, MA 02111 USA
+
+ */
+#include <stdio.h>
+#include "defs.h"
+#include "grtcirc.h"
+
+#define MYNAME "Route simplification filter"
+
+static int count = 0;
+static char *countopt = NULL;
+
+static
+arglist_t routesimple_args[] = {
+ {"count", &countopt, "Maximum number of points in final route",
+ ARGTYPE_INT | ARGTYPE_REQUIRED},
+ {0, 0, 0, 0}
+};
+
+struct xte_intermed;
+
+struct xte {
+ double distance;
+ int ordinal;
+ struct xte_intermed *intermed;
+};
+
+struct xte_intermed {
+ struct xte *xte_rec;
+ struct xte_intermed *next;
+ struct xte_intermed *prev;
+ const waypoint *wpt;
+};
+
+void
+free_xte( struct xte *xte_rec )
+{
+ xfree(xte_rec->intermed);
+}
+
+#define HUGEVAL 9e9;
+
+static struct xte_intermed *tmpprev = NULL;
+static int xte_count = 0;
+static const route_head *cur_rte = NULL;
+static struct xte *xte_recs = NULL;
+
+void
+routesimple_waypt_pr( const waypoint *wpt )
+{
+ if ( !cur_rte ) return;
+ xte_recs[xte_count].ordinal=xte_count;
+ xte_recs[xte_count].intermed = xmalloc( sizeof(struct xte_intermed));
+ xte_recs[xte_count].intermed->wpt = wpt;
+ xte_recs[xte_count].intermed->xte_rec = xte_recs+xte_count;
+ xte_recs[xte_count].intermed->next = NULL;
+ xte_recs[xte_count].intermed->prev = tmpprev;
+ if ( tmpprev ) {
+ tmpprev->next = xte_recs[xte_count].intermed;
+ }
+ tmpprev = xte_recs[xte_count].intermed;
+ xte_count++;
+}
+
+void
+compute_xte( struct xte *xte_rec ) {
+ const waypoint *wpt3 = xte_rec->intermed->wpt;
+ const waypoint *wpt1 = NULL;
+ const waypoint *wpt2 = NULL;
+ /* if no previous, this is an endpoint and must be preserved. */
+ if ( !xte_rec->intermed->prev ) {
+ xte_rec->distance = HUGEVAL;
+ return;
+ }
+ wpt1 = xte_rec->intermed->prev->wpt;
+
+ /* if no next, this is an endpoint and must be preserved. */
+ if ( !xte_rec->intermed->next ) {
+ xte_rec->distance = HUGEVAL;
+ return;
+ }
+ wpt2 = xte_rec->intermed->next->wpt;
+
+ xte_rec->distance = linedist(
+ wpt1->latitude, wpt1->longitude,
+ wpt2->latitude, wpt2->longitude,
+ wpt3->latitude, wpt3->longitude );
+}
+
+
+int
+compare_xte( const void *a, const void *b )
+{
+ double foo = (((struct xte *)a)->distance - ((struct xte *)b)->distance );
+ if ( foo < 0 ) return 1;
+ if ( foo > 0 ) return -1;
+ return 0;
+}
+
+void
+routesimple_head( const route_head *rte )
+{
+ cur_rte = NULL;
+ /* build array of XTE/wpt xref records */
+ xte_count = 0;
+ tmpprev = NULL;
+
+ /* short-circuit if we already have fewer than the max points */
+ if ( count >= rte->rte_waypt_ct) return;
+
+ xte_recs = xcalloc( rte->rte_waypt_ct, sizeof (struct xte));
+ cur_rte = rte;
+
+}
+
+void
+shuffle_xte( struct xte *xte_rec )
+{
+ struct xte tmp_xte;
+ while ( xte_rec > xte_recs &&
+ xte_rec->distance > xte_rec[-1].distance ) {
+ tmp_xte.distance = xte_rec->distance;
+ tmp_xte.ordinal = xte_rec->ordinal;
+ tmp_xte.intermed = xte_rec->intermed;
+ xte_rec->distance = xte_rec[-1].distance;
+ xte_rec->ordinal = xte_rec[-1].ordinal;
+ xte_rec->intermed = xte_rec[-1].intermed;
+ xte_rec->intermed->xte_rec = xte_rec;
+ xte_rec--;
+ xte_rec->distance = tmp_xte.distance;
+ xte_rec->ordinal = tmp_xte.ordinal;
+ xte_rec->intermed = tmp_xte.intermed;
+ xte_rec->intermed->xte_rec = xte_rec;
+ }
+ while ( xte_rec - xte_recs < xte_count-2 &&
+ xte_rec->distance < xte_rec[1].distance ) {
+ tmp_xte.distance = xte_rec->distance;
+ tmp_xte.ordinal = xte_rec->ordinal;
+ tmp_xte.intermed = xte_rec->intermed;
+ xte_rec->distance = xte_rec[1].distance;
+ xte_rec->ordinal = xte_rec[1].ordinal;
+ xte_rec->intermed = xte_rec[1].intermed;
+ xte_rec->intermed->xte_rec = xte_rec;
+ xte_rec++;
+ xte_rec->distance = tmp_xte.distance;
+ xte_rec->ordinal = tmp_xte.ordinal;
+ xte_rec->intermed = tmp_xte.intermed;
+ xte_rec->intermed->xte_rec = xte_rec;
+ }
+}
+
+void
+routesimple_tail( const route_head *rte )
+{
+ int i;
+ if ( !cur_rte ) return;
+
+ /* compute all distances */
+ for (i = 0; i < xte_count ; i++ ) {
+ compute_xte( xte_recs+i );
+ }
+
+
+ /* sort XTE array, lowest XTE last */
+ qsort( xte_recs, xte_count, sizeof( struct xte ), compare_xte );
+
+ for (i = 0; i < xte_count; i++ ) {
+ xte_recs[i].intermed->xte_rec = xte_recs+i;
+ }
+ /* while we still have too many records... */
+ while ( count < xte_count ) {
+ i = xte_count - 1;
+ /* remove the record with the lowest XTE */
+ route_del_wpt( (route_head *)(void *)rte,
+ (waypoint *)(void *)(xte_recs[i].intermed->wpt));
+
+ if ( xte_recs[i].intermed->prev ) {
+ xte_recs[i].intermed->prev->next = xte_recs[i].intermed->next;
+ compute_xte(xte_recs[i].intermed->prev->xte_rec);
+ shuffle_xte(xte_recs[i].intermed->prev->xte_rec);
+ }
+ if ( xte_recs[i].intermed->next ) {
+ xte_recs[i].intermed->next->prev = xte_recs[i].intermed->prev;
+ compute_xte(xte_recs[i].intermed->next->xte_rec);
+ shuffle_xte(xte_recs[i].intermed->next->xte_rec);
+ }
+ xte_count--;
+ free_xte( xte_recs+xte_count);
+ /* end of loop */
+ }
+ if ( xte_count ) {
+ do {
+ xte_count--;
+ free_xte( xte_recs+xte_count );
+ } while(xte_count);
+ }
+ xfree( xte_recs );
+}
+
+void
+routesimple_process( void )
+{
+ route_disp_all( routesimple_head, routesimple_tail, routesimple_waypt_pr );
+}
+
+void
+routesimple_init(const char *args) {
+ char *fm;
+
+ count = 0;
+
+ if ( global_opts.objective != rtedata &&
+ global_opts.objective != trkdata ) {
+ fatal(MYNAME ": This filter only works in route (-r) mode.");
+ }
+ if (countopt) {
+ count = atol(countopt);
+ }
+ else {
+ fatal( MYNAME ": You must specify a maximum size for the new route");
+ }
+}
+
+void
+routesimple_deinit(void) {
+ /* do nothing */
+}
+
+filter_vecs_t routesimple_vecs = {
+ routesimple_init,
+ routesimple_process,
+ routesimple_deinit,
+ routesimple_args
+};
projects / gpsbabel.git / commitdiff