trunk/src/segments.c

/***************************************
 $Header: /home/amb/CVS/routino/src/segments.c,v 1.37 2009-04-08 16:54:34 amb Exp $

 Segment data type functions.

 Part of the Routino routing software.
 ******************/ /******************
 This file Copyright 2008,2009 Andrew M. Bishop

 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU Affero General Public License as published by
 the Free Software Foundation, either version 3 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 Affero General Public License for more details.

 You should have received a copy of the GNU Affero General Public License
 along with this program.  If not, see <http://www.gnu.org/licenses/>.
 ***************************************/


#include <assert.h>
#include <math.h>
#include <string.h>
#include <stdlib.h>

#include "types.h"
#include "functions.h"
#include "nodes.h"
#include "segments.h"
#include "ways.h"
#include "profiles.h"


/*++++++++++++++++++++++++++++++++++++++
  Load in a segment list from a file.

  Segments* SaveSegmentList Returns the segment list that has just been loaded.

  const char *filename The name of the file to load.
  ++++++++++++++++++++++++++++++++++++++*/

Segments *LoadSegmentList(const char *filename)
{
 void *data;
 Segments *segments;

 segments=(Segments*)malloc(sizeof(Segments));

 data=MapFile(filename);

 if(!data)
    return(NULL);

 /* Copy the Segments structure from the loaded data */

 *segments=*((Segments*)data);

 /* Adjust the pointers in the Segments structure. */

 segments->data=data;
 segments->segments=(Segment*)(data+(off_t)segments->segments);

 return(segments);
}


/*++++++++++++++++++++++++++++++++++++++
  Find the next segment with a particular starting node.

  Segment *NextSegment Returns a pointer to the next segment with the same id.

  Segments* segments The set of segments to process.

  Segment *segment The current segment.
  ++++++++++++++++++++++++++++++++++++++*/

Segment *NextSegment(Segments* segments,Segment *segment,index_t node)
{
 if(NODE(segment->node1)==node)
   {
    segment++;
    if(NODE(segment->node1)!=node || (segment-segments->segments)>=segments->number)
       return(NULL);
    else
       return(segment);
   }
 else
   {
    if(segment->next2==~0)
       return(NULL);
    else
       return(LookupSegment(segments,segment->next2));
   }
}
 
 
/*++++++++++++++++++++++++++++++++++++++
  Calculate the distance between two locations.

  distance_t Distance Returns the distance between the locations.

  float lat1 The latitude of the first location.

  float lon1 The longitude of the first location.

  float lat2 The latitude of the second location.

  float lon2 The longitude of the second location.
  ++++++++++++++++++++++++++++++++++++++*/

distance_t Distance(float lat1,float lon1,float lat2,float lon2)
{
 float dlon = lon1 - lon2;
 float dlat = lat1 - lat2;

 float a1,a2,a,sa,c,d;

 if(dlon==0 && dlat==0)
   return 0;

 a1 = sinf (dlat / 2);
 a2 = sinf (dlon / 2);
 a = (a1 * a1) + cosf (lat1) * cosf (lat2) * a2 * a2;
 sa = sqrtf (a);
 if (sa <= 1.0)
   {c = 2 * asinf (sa);}
 else
   {c = 2 * asinf (1.0);}
 d = 6378.137 * c;

 return km_to_distance(d);
}


/*++++++++++++++++++++++++++++++++++++++
  Calculate the duration of segment.

  duration_t Duration Returns the duration of travel between the nodes.

  Segment *segment The segment to traverse.

  Way *way The way that the segment belongs to.

  Profile *profile The profile of the transport being used.
  ++++++++++++++++++++++++++++++++++++++*/

duration_t Duration(Segment *segment,Way *way,Profile *profile)
{
 speed_t    speed1=way->speed;
 speed_t    speed2=profile->speed[HIGHWAY(way->type)];
 distance_t distance=DISTANCE(segment->distance);

 if(speed1==0)
   {
    if(speed2==0)
       return(hours_to_duration(10));
    else
       return distance_speed_to_duration(distance,speed2);
   }
 else /* if(speed1!=0) */
   {
    if(speed2==0)
       return distance_speed_to_duration(distance,speed1);
    else if(speed1<=speed2)
       return distance_speed_to_duration(distance,speed1);
    else
       return distance_speed_to_duration(distance,speed2);
   }
}
1	amb	2	/***************************************
2	amb	151	$Header: /home/amb/CVS/routino/src/segments.c,v 1.37 2009-04-08 16:54:34 amb Exp $
3	amb	2
4			Segment data type functions.
5	amb	151
6			Part of the Routino routing software.
7	amb	2	****************/ /****************
8	amb	151	This file Copyright 2008,2009 Andrew M. Bishop
9	amb	2
10	amb	151	This program is free software: you can redistribute it and/or modify
11			it under the terms of the GNU Affero General Public License as published by
12			the Free Software Foundation, either version 3 of the License, or
13			(at your option) any later version.
14
15			This program is distributed in the hope that it will be useful,
16			but WITHOUT ANY WARRANTY; without even the implied warranty of
17			MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18			GNU Affero General Public License for more details.
19
20			You should have received a copy of the GNU Affero General Public License
21			along with this program. If not, see <http://www.gnu.org/licenses/>.
22	amb	2	***************************************/
23
24
25	amb	8	#include <assert.h>
26	amb	2	#include <math.h>
27	amb	104	#include <string.h>
28	amb	2	#include <stdlib.h>
29
30	amb	109	#include "types.h"
31			#include "functions.h"
32	amb	39	#include "nodes.h"
33	amb	26	#include "segments.h"
34	amb	109	#include "ways.h"
35			#include "profiles.h"
36	amb	2
37
38	amb	23	/*++++++++++++++++++++++++++++++++++++++
39	amb	2	Load in a segment list from a file.
40
41	amb	23	Segments* SaveSegmentList Returns the segment list that has just been loaded.
42
43	amb	2	const char *filename The name of the file to load.
44			++++++++++++++++++++++++++++++++++++++*/
45
46	amb	23	Segments LoadSegmentList(const char filename)
47	amb	2	{
48	amb	88	void *data;
49			Segments *segments;
50
51			segments=(Segments*)malloc(sizeof(Segments));
52
53			data=MapFile(filename);
54
55	amb	100	if(!data)
56			return(NULL);
57
58	amb	88	/* Copy the Segments structure from the loaded data */
59
60			segments=((Segments*)data);
61
62			/* Adjust the pointers in the Segments structure. */
63
64	amb	104	segments->data=data;
65	amb	88	segments->segments=(Segment*)(data+(off_t)segments->segments);
66
67			return(segments);
68	amb	2	}
69
70
71			/*++++++++++++++++++++++++++++++++++++++
72			Find the next segment with a particular starting node.
73
74	amb	88	Segment *NextSegment Returns a pointer to the next segment with the same id.
75	amb	2
76	amb	23	Segments* segments The set of segments to process.
77
78	amb	2	Segment *segment The current segment.
79			++++++++++++++++++++++++++++++++++++++*/
80
81	amb	104	Segment NextSegment(Segments segments,Segment *segment,index_t node)
82	amb	2	{
83	amb	104	if(NODE(segment->node1)==node)
84	amb	128	{
85			segment++;
86			if(NODE(segment->node1)!=node \|\| (segment-segments->segments)>=segments->number)
87			return(NULL);
88			else
89			return(segment);
90			}
91	amb	104	else
92	amb	128	{
93			if(segment->next2==~0)
94			return(NULL);
95			else
96			return(LookupSegment(segments,segment->next2));
97			}
98	amb	89	}
99	amb	88
100
101	amb	2	/*++++++++++++++++++++++++++++++++++++++
102	amb	99	Calculate the distance between two locations.
103
104	amb	114	distance_t Distance Returns the distance between the locations.
105	amb	99
106			float lat1 The latitude of the first location.
107
108			float lon1 The longitude of the first location.
109
110			float lat2 The latitude of the second location.
111
112			float lon2 The longitude of the second location.
113			++++++++++++++++++++++++++++++++++++++*/
114
115	amb	114	distance_t Distance(float lat1,float lon1,float lat2,float lon2)
116	amb	99	{
117	amb	121	float dlon = lon1 - lon2;
118			float dlat = lat1 - lat2;
119	amb	99
120	amb	120	float a1,a2,a,sa,c,d;
121	amb	99
122			if(dlon==0 && dlat==0)
123			return 0;
124
125	amb	120	a1 = sinf (dlat / 2);
126			a2 = sinf (dlon / 2);
127	amb	121	a = (a1 * a1) + cosf (lat1) * cosf (lat2) * a2 * a2;
128	amb	120	sa = sqrtf (a);
129	amb	99	if (sa <= 1.0)
130	amb	120	{c = 2 * asinf (sa);}
131	amb	99	else
132	amb	120	{c = 2 * asinf (1.0);}
133	amb	99	d = 6378.137 * c;
134
135	amb	114	return km_to_distance(d);
136	amb	99	}
137
138
139			/*++++++++++++++++++++++++++++++++++++++
140	amb	63	Calculate the duration of segment.
141
142			duration_t Duration Returns the duration of travel between the nodes.
143
144			Segment *segment The segment to traverse.
145
146			Way *way The way that the segment belongs to.
147
148	amb	82	Profile *profile The profile of the transport being used.
149	amb	63	++++++++++++++++++++++++++++++++++++++*/
150
151	amb	82	duration_t Duration(Segment segment,Way way,Profile *profile)
152	amb	63	{
153	amb	137	speed_t speed1=way->speed;
154			speed_t speed2=profile->speed[HIGHWAY(way->type)];
155	amb	90	distance_t distance=DISTANCE(segment->distance);
156	amb	63
157	amb	137	if(speed1==0)
158			{
159			if(speed2==0)
160			return(hours_to_duration(10));
161			else
162			return distance_speed_to_duration(distance,speed2);
163			}
164			else /* if(speed1!=0) */
165			{
166			if(speed2==0)
167			return distance_speed_to_duration(distance,speed1);
168			else if(speed1<=speed2)
169			return distance_speed_to_duration(distance,speed1);
170			else
171			return distance_speed_to_duration(distance,speed2);
172			}
173	amb	63	}