/*
* viking -- GPS Data and Topo Analyzer, Explorer, and Manager
*
* Copyright (C) 2003-2005, Evan Battaglia <gtoevan@gmx.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 02111-1307 USA
*
*/
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <glib.h>
#include <time.h>
#include <stdlib.h>
#ifdef HAVE_STRING_H
#include <string.h>
#endif
#ifdef HAVE_MATH_H
#include <math.h>
#endif
#include "coords.h"
#include "vikcoord.h"
#include "viktrack.h"
#include "globals.h"
#include "dems.h"
VikTrack *vik_track_new()
{
VikTrack *tr = g_malloc0 ( sizeof ( VikTrack ) );
tr->ref_count = 1;
return tr;
}
void vik_track_set_comment_no_copy(VikTrack *tr, gchar *comment)
{
if ( tr->comment )
g_free ( tr->comment );
tr->comment = comment;
}
void vik_track_set_comment(VikTrack *tr, const gchar *comment)
{
if ( tr->comment )
g_free ( tr->comment );
if ( comment && comment[0] != '\0' )
tr->comment = g_strdup(comment);
else
tr->comment = NULL;
}
void vik_track_ref(VikTrack *tr)
{
tr->ref_count++;
}
void vik_track_set_property_dialog(VikTrack *tr, GtkWidget *dialog)
{
/* Warning: does not check for existing dialog */
tr->property_dialog = dialog;
}
void vik_track_clear_property_dialog(VikTrack *tr)
{
tr->property_dialog = NULL;
}
void vik_track_free(VikTrack *tr)
{
if ( tr->ref_count-- > 1 )
return;
if ( tr->comment )
g_free ( tr->comment );
g_list_foreach ( tr->trackpoints, (GFunc) g_free, NULL );
g_list_free( tr->trackpoints );
if (tr->property_dialog)
if ( GTK_IS_WIDGET(tr->property_dialog) )
gtk_widget_destroy ( GTK_WIDGET(tr->property_dialog) );
g_free ( tr );
}
VikTrack *vik_track_copy ( const VikTrack *tr )
{
VikTrack *new_tr = vik_track_new();
VikTrackpoint *new_tp;
GList *tp_iter = tr->trackpoints;
new_tr->visible = tr->visible;
new_tr->trackpoints = NULL;
while ( tp_iter )
{
new_tp = g_malloc ( sizeof ( VikTrackpoint ) );
*new_tp = *((VikTrackpoint *)(tp_iter->data));
new_tr->trackpoints = g_list_append ( new_tr->trackpoints, new_tp );
tp_iter = tp_iter->next;
}
vik_track_set_comment(new_tr,tr->comment);
return new_tr;
}
VikTrackpoint *vik_trackpoint_new()
{
VikTrackpoint *tp = g_malloc0(sizeof(VikTrackpoint));
tp->speed = NAN;
tp->course = NAN;
tp->altitude = VIK_DEFAULT_ALTITUDE;
tp->hdop = VIK_DEFAULT_DOP;
tp->vdop = VIK_DEFAULT_DOP;
tp->pdop = VIK_DEFAULT_DOP;
return tp;
}
void vik_trackpoint_free(VikTrackpoint *tp)
{
g_free(tp);
}
VikTrackpoint *vik_trackpoint_copy(VikTrackpoint *tp)
{
VikTrackpoint *rv = vik_trackpoint_new();
*rv = *tp;
return rv;
}
gdouble vik_track_get_length(const VikTrack *tr)
{
gdouble len = 0.0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
if ( ! VIK_TRACKPOINT(iter->data)->newsegment )
len += vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->prev->data)->coord) );
iter = iter->next;
}
}
return len;
}
gdouble vik_track_get_length_including_gaps(const VikTrack *tr)
{
gdouble len = 0.0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
len += vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->prev->data)->coord) );
iter = iter->next;
}
}
return len;
}
gulong vik_track_get_tp_count(const VikTrack *tr)
{
gulong num = 0;
GList *iter = tr->trackpoints;
while ( iter )
{
num++;
iter = iter->next;
}
return num;
}
gulong vik_track_get_dup_point_count ( const VikTrack *tr )
{
gulong num = 0;
GList *iter = tr->trackpoints;
while ( iter )
{
if ( iter->next && vik_coord_equals ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->next->data)->coord) ) )
num++;
iter = iter->next;
}
return num;
}
void vik_track_remove_dup_points ( VikTrack *tr )
{
GList *iter = tr->trackpoints;
while ( iter )
{
if ( iter->next && vik_coord_equals ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->next->data)->coord) ) )
{
g_free ( iter->next->data );
tr->trackpoints = g_list_delete_link ( tr->trackpoints, iter->next );
}
else
iter = iter->next;
}
}
guint vik_track_get_segment_count(const VikTrack *tr)
{
guint num = 1;
GList *iter = tr->trackpoints;
if ( !iter )
return 0;
while ( (iter = iter->next) )
{
if ( VIK_TRACKPOINT(iter->data)->newsegment )
num++;
}
return num;
}
VikTrack **vik_track_split_into_segments(VikTrack *t, guint *ret_len)
{
VikTrack **rv;
VikTrack *tr;
guint i;
guint segs = vik_track_get_segment_count(t);
GList *iter;
if ( segs < 2 )
{
*ret_len = 0;
return NULL;
}
rv = g_malloc ( segs * sizeof(VikTrack *) );
tr = vik_track_copy ( t );
rv[0] = tr;
iter = tr->trackpoints;
i = 1;
while ( (iter = iter->next) )
{
if ( VIK_TRACKPOINT(iter->data)->newsegment )
{
iter->prev->next = NULL;
iter->prev = NULL;
rv[i] = vik_track_new();
if ( tr->comment )
vik_track_set_comment ( rv[i], tr->comment );
rv[i]->visible = tr->visible;
rv[i]->trackpoints = iter;
i++;
}
}
*ret_len = segs;
return rv;
}
void vik_track_reverse ( VikTrack *tr )
{
GList *iter;
tr->trackpoints = g_list_reverse(tr->trackpoints);
/* fix 'newsegment' */
iter = g_list_last ( tr->trackpoints );
while ( iter )
{
if ( ! iter->next ) /* last segment, was first, cancel newsegment. */
VIK_TRACKPOINT(iter->data)->newsegment = FALSE;
if ( ! iter->prev ) /* first segment by convention has newsegment flag. */
VIK_TRACKPOINT(iter->data)->newsegment = TRUE;
else if ( VIK_TRACKPOINT(iter->data)->newsegment && iter->next )
{
VIK_TRACKPOINT(iter->next->data)->newsegment = TRUE;
VIK_TRACKPOINT(iter->data)->newsegment = FALSE;
}
iter = iter->prev;
}
}
gdouble vik_track_get_average_speed(const VikTrack *tr)
{
gdouble len = 0.0;
guint32 time = 0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
if ( VIK_TRACKPOINT(iter->data)->has_timestamp &&
VIK_TRACKPOINT(iter->prev->data)->has_timestamp &&
(! VIK_TRACKPOINT(iter->data)->newsegment) )
{
len += vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->prev->data)->coord) );
time += ABS(VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(iter->prev->data)->timestamp);
}
iter = iter->next;
}
}
return (time == 0) ? 0 : ABS(len/time);
}
/**
* Based on a simple average speed, but with a twist - to give a moving average.
* . GPSs often report a moving average in their statistics output
* . bicycle speedos often don't factor in time when stopped - hence reporting a moving average for speed
*
* Often GPS track will record every second but not when stationary
* This method doesn't use samples that differ over the specified time limit - effectively skipping that time chunk from the total time
*
* Suggest to use 60 seconds as the stop length (as the default used in the TrackWaypoint draw stops factor)
*/
gdouble vik_track_get_average_speed_moving (const VikTrack *tr, int stop_length_seconds)
{
gdouble len = 0.0;
guint32 time = 0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
if ( VIK_TRACKPOINT(iter->data)->has_timestamp &&
VIK_TRACKPOINT(iter->prev->data)->has_timestamp &&
(! VIK_TRACKPOINT(iter->data)->newsegment) )
{
if ( ( VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(iter->prev->data)->timestamp ) < stop_length_seconds ) {
len += vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->prev->data)->coord) );
time += ABS(VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(iter->prev->data)->timestamp);
}
}
iter = iter->next;
}
}
return (time == 0) ? 0 : ABS(len/time);
}
gdouble vik_track_get_max_speed(const VikTrack *tr)
{
gdouble maxspeed = 0.0, speed = 0.0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
if ( VIK_TRACKPOINT(iter->data)->has_timestamp &&
VIK_TRACKPOINT(iter->prev->data)->has_timestamp &&
(! VIK_TRACKPOINT(iter->data)->newsegment) )
{
speed = vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord), &(VIK_TRACKPOINT(iter->prev->data)->coord) )
/ ABS(VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(iter->prev->data)->timestamp);
if ( speed > maxspeed )
maxspeed = speed;
}
iter = iter->next;
}
}
return maxspeed;
}
void vik_track_convert ( VikTrack *tr, VikCoordMode dest_mode )
{
GList *iter = tr->trackpoints;
while (iter)
{
vik_coord_convert ( &(VIK_TRACKPOINT(iter->data)->coord), dest_mode );
iter = iter->next;
}
}
/* I understood this when I wrote it ... maybe ... Basically it eats up the
* proper amounts of length on the track and averages elevation over that. */
gdouble *vik_track_make_elevation_map ( const VikTrack *tr, guint16 num_chunks )
{
gdouble *pts;
gdouble total_length, chunk_length, current_dist, current_area_under_curve, current_seg_length, dist_along_seg = 0.0;
gdouble altitude1, altitude2;
guint16 current_chunk;
gboolean ignore_it = FALSE;
GList *iter = tr->trackpoints;
if (!iter || !iter->next) /* zero- or one-point track */
return NULL;
{ /* test if there's anything worth calculating */
gboolean okay = FALSE;
while ( iter )
{
if ( VIK_TRACKPOINT(iter->data)->altitude != VIK_DEFAULT_ALTITUDE ) {
okay = TRUE; break;
}
iter = iter->next;
}
if ( ! okay )
return NULL;
}
iter = tr->trackpoints;
g_assert ( num_chunks < 16000 );
pts = g_malloc ( sizeof(gdouble) * num_chunks );
total_length = vik_track_get_length_including_gaps ( tr );
chunk_length = total_length / num_chunks;
/* Zero chunk_length (eg, track of 2 tp with the same loc) will cause crash */
if (chunk_length <= 0) {
g_free(pts);
return NULL;
}
current_dist = 0.0;
current_area_under_curve = 0;
current_chunk = 0;
current_seg_length = 0;
current_seg_length = vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->next->data)->coord) );
altitude1 = VIK_TRACKPOINT(iter->data)->altitude;
altitude2 = VIK_TRACKPOINT(iter->next->data)->altitude;
dist_along_seg = 0;
while ( current_chunk < num_chunks ) {
/* go along current seg */
if ( current_seg_length && (current_seg_length - dist_along_seg) > chunk_length ) {
dist_along_seg += chunk_length;
/* /
* pt2 *
* /x altitude = alt_at_pt_1 + alt_at_pt_2 / 2 = altitude1 + slope * dist_value_of_pt_inbetween_pt1_and_pt2
* /xx avg altitude = area under curve / chunk len
*pt1 *xxx avg altitude = altitude1 + (altitude2-altitude1)/(current_seg_length)*(dist_along_seg + (chunk_len/2))
* / xxx
* / xxx
**/
if ( ignore_it )
// Seemly can't determine average for this section - so use last known good value (much better than just sticking in zero)
pts[current_chunk] = altitude1;
else
pts[current_chunk] = altitude1 + (altitude2-altitude1)*((dist_along_seg - (chunk_length/2))/current_seg_length);
current_chunk++;
} else {
/* finish current seg */
if ( current_seg_length ) {
gdouble altitude_at_dist_along_seg = altitude1 + (altitude2-altitude1)/(current_seg_length)*dist_along_seg;
current_dist = current_seg_length - dist_along_seg;
current_area_under_curve = current_dist*(altitude_at_dist_along_seg + altitude2)*0.5;
} else { current_dist = current_area_under_curve = 0; } /* should only happen if first current_seg_length == 0 */
/* get intervening segs */
iter = iter->next;
while ( iter && iter->next ) {
current_seg_length = vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->next->data)->coord) );
altitude1 = VIK_TRACKPOINT(iter->data)->altitude;
altitude2 = VIK_TRACKPOINT(iter->next->data)->altitude;
ignore_it = VIK_TRACKPOINT(iter->next->data)->newsegment;
if ( chunk_length - current_dist >= current_seg_length ) {
current_dist += current_seg_length;
current_area_under_curve += current_seg_length * (altitude1+altitude2) * 0.5;
iter = iter->next;
} else {
break;
}
}
/* final seg */
dist_along_seg = chunk_length - current_dist;
if ( ignore_it || ( iter && !iter->next ) ) {
pts[current_chunk] = current_area_under_curve / current_dist;
if (!iter->next) {
int i;
for (i = current_chunk + 1; i < num_chunks; i++)
pts[i] = pts[current_chunk];
break;
}
}
else {
current_area_under_curve += dist_along_seg * (altitude1 + (altitude2 - altitude1)*dist_along_seg/current_seg_length);
pts[current_chunk] = current_area_under_curve / chunk_length;
}
current_dist = 0;
current_chunk++;
}
}
return pts;
}
void vik_track_get_total_elevation_gain(const VikTrack *tr, gdouble *up, gdouble *down)
{
gdouble diff;
*up = *down = 0;
if ( tr->trackpoints && VIK_TRACKPOINT(tr->trackpoints->data)->altitude != VIK_DEFAULT_ALTITUDE )
{
GList *iter = tr->trackpoints->next;
while (iter)
{
diff = VIK_TRACKPOINT(iter->data)->altitude - VIK_TRACKPOINT(iter->prev->data)->altitude;
if ( diff > 0 )
*up += diff;
else
*down -= diff;
iter = iter->next;
}
} else
*up = *down = VIK_DEFAULT_ALTITUDE;
}
/* by Alex Foobarian */
gdouble *vik_track_make_speed_map ( const VikTrack *tr, guint16 num_chunks )
{
gdouble *v, *s, *t;
gdouble duration, chunk_dur;
time_t t1, t2;
int i, pt_count, numpts, index;
GList *iter;
if ( ! tr->trackpoints )
return NULL;
g_assert ( num_chunks < 16000 );
t1 = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
t2 = VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->timestamp;
duration = t2 - t1;
if ( !t1 || !t2 || !duration )
return NULL;
if (duration < 0) {
g_warning("negative duration: unsorted trackpoint timestamps?");
return NULL;
}
pt_count = vik_track_get_tp_count(tr);
v = g_malloc ( sizeof(gdouble) * num_chunks );
chunk_dur = duration / num_chunks;
s = g_malloc(sizeof(double) * pt_count);
t = g_malloc(sizeof(double) * pt_count);
iter = tr->trackpoints->next;
numpts = 0;
s[0] = 0;
t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
numpts++;
while (iter) {
s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );
t[numpts] = VIK_TRACKPOINT(iter->data)->timestamp;
numpts++;
iter = iter->next;
}
/* In the following computation, we iterate through periods of time of duration chunk_dur.
* The first period begins at the beginning of the track. The last period ends at the end of the track.
*/
index = 0; /* index of the current trackpoint. */
for (i = 0; i < num_chunks; i++) {
/* we are now covering the interval from t[0] + i*chunk_dur to t[0] + (i+1)*chunk_dur.
* find the first trackpoint outside the current interval, averaging the speeds between intermediate trackpoints.
*/
if (t[0] + i*chunk_dur >= t[index]) {
gdouble acc_t = 0, acc_s = 0;
while (t[0] + i*chunk_dur >= t[index]) {
acc_s += (s[index+1]-s[index]);
acc_t += (t[index+1]-t[index]);
index++;
}
v[i] = acc_s/acc_t;
}
else if (i) {
v[i] = v[i-1];
}
else {
v[i] = 0;
}
}
g_free(s);
g_free(t);
return v;
}
/**
* Make a distance/time map, heavily based on the vik_track_make_speed_map method
*/
gdouble *vik_track_make_distance_map ( const VikTrack *tr, guint16 num_chunks )
{
gdouble *v, *s, *t;
gdouble duration, chunk_dur;
time_t t1, t2;
int i, pt_count, numpts, index;
GList *iter;
if ( ! tr->trackpoints )
return NULL;
t1 = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
t2 = VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->timestamp;
duration = t2 - t1;
if ( !t1 || !t2 || !duration )
return NULL;
if (duration < 0) {
g_warning("negative duration: unsorted trackpoint timestamps?");
return NULL;
}
pt_count = vik_track_get_tp_count(tr);
v = g_malloc ( sizeof(gdouble) * num_chunks );
chunk_dur = duration / num_chunks;
s = g_malloc(sizeof(double) * pt_count);
t = g_malloc(sizeof(double) * pt_count);
iter = tr->trackpoints->next;
numpts = 0;
s[0] = 0;
t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
numpts++;
while (iter) {
s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );
t[numpts] = VIK_TRACKPOINT(iter->data)->timestamp;
numpts++;
iter = iter->next;
}
/* In the following computation, we iterate through periods of time of duration chunk_dur.
* The first period begins at the beginning of the track. The last period ends at the end of the track.
*/
index = 0; /* index of the current trackpoint. */
for (i = 0; i < num_chunks; i++) {
/* we are now covering the interval from t[0] + i*chunk_dur to t[0] + (i+1)*chunk_dur.
* find the first trackpoint outside the current interval, averaging the distance between intermediate trackpoints.
*/
if (t[0] + i*chunk_dur >= t[index]) {
gdouble acc_s = 0; // No need for acc_t
while (t[0] + i*chunk_dur >= t[index]) {
acc_s += (s[index+1]-s[index]);
index++;
}
// The only bit that's really different from the speed map - just keep an accululative record distance
v[i] = i ? v[i-1]+acc_s : acc_s;
}
else if (i) {
v[i] = v[i-1];
}
else {
v[i] = 0;
}
}
g_free(s);
g_free(t);
return v;
}
/**
* This uses the 'time' based method to make the graph, (which is a simpler compared to the elevation/distance)
* This results in a slightly blocky graph when it does not have many trackpoints: <60
* NB Somehow the elevation/distance applies some kind of smoothing algorithm,
* but I don't think any one understands it any more (I certainly don't ATM)
*/
gdouble *vik_track_make_elevation_time_map ( const VikTrack *tr, guint16 num_chunks )
{
time_t t1, t2;
gdouble duration, chunk_dur;
GList *iter = tr->trackpoints;
if (!iter || !iter->next) /* zero- or one-point track */
return NULL;
/* test if there's anything worth calculating */
gboolean okay = FALSE;
while ( iter ) {
if ( VIK_TRACKPOINT(iter->data)->altitude != VIK_DEFAULT_ALTITUDE ) {
okay = TRUE;
break;
}
iter = iter->next;
}
if ( ! okay )
return NULL;
t1 = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
t2 = VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->timestamp;
duration = t2 - t1;
if ( !t1 || !t2 || !duration )
return NULL;
if (duration < 0) {
g_warning("negative duration: unsorted trackpoint timestamps?");
return NULL;
}
gint pt_count = vik_track_get_tp_count(tr);
// Reset iterator back to the beginning
iter = tr->trackpoints;
gdouble *pts = g_malloc ( sizeof(gdouble) * num_chunks ); // The return altitude values
gdouble *s = g_malloc(sizeof(double) * pt_count); // calculation altitudes
gdouble *t = g_malloc(sizeof(double) * pt_count); // calculation times
chunk_dur = duration / num_chunks;
s[0] = VIK_TRACKPOINT(iter->data)->altitude;
t[0] = VIK_TRACKPOINT(iter->data)->timestamp;
iter = tr->trackpoints->next;
gint numpts = 1;
while (iter) {
s[numpts] = VIK_TRACKPOINT(iter->data)->altitude;
t[numpts] = VIK_TRACKPOINT(iter->data)->timestamp;
numpts++;
iter = iter->next;
}
/* In the following computation, we iterate through periods of time of duration chunk_dur.
* The first period begins at the beginning of the track. The last period ends at the end of the track.
*/
gint index = 0; /* index of the current trackpoint. */
gint i;
for (i = 0; i < num_chunks; i++) {
/* we are now covering the interval from t[0] + i*chunk_dur to t[0] + (i+1)*chunk_dur.
* find the first trackpoint outside the current interval, averaging the heights between intermediate trackpoints.
*/
if (t[0] + i*chunk_dur >= t[index]) {
gdouble acc_s = s[index]; // initialise to first point
while (t[0] + i*chunk_dur >= t[index]) {
acc_s += (s[index+1]-s[index]);
index++;
}
pts[i] = acc_s;
}
else if (i) {
pts[i] = pts[i-1];
}
else {
pts[i] = 0;
}
}
g_free(s);
g_free(t);
return pts;
}
/**
* Make a speed/distance map
*/
gdouble *vik_track_make_speed_dist_map ( const VikTrack *tr, guint16 num_chunks )
{
gdouble *v, *s, *t;
time_t t1, t2;
gint i, pt_count, numpts, index;
GList *iter;
gdouble duration, total_length, chunk_length;
if ( ! tr->trackpoints )
return NULL;
t1 = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
t2 = VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->timestamp;
duration = t2 - t1;
if ( !t1 || !t2 || !duration )
return NULL;
if (duration < 0) {
g_warning("negative duration: unsorted trackpoint timestamps?");
return NULL;
}
total_length = vik_track_get_length_including_gaps ( tr );
chunk_length = total_length / num_chunks;
pt_count = vik_track_get_tp_count(tr);
if (chunk_length <= 0) {
return NULL;
}
v = g_malloc ( sizeof(gdouble) * num_chunks );
s = g_malloc ( sizeof(double) * pt_count );
t = g_malloc ( sizeof(double) * pt_count );
// No special handling of segments ATM...
iter = tr->trackpoints->next;
numpts = 0;
s[0] = 0;
t[0] = VIK_TRACKPOINT(iter->prev->data)->timestamp;
numpts++;
while (iter) {
s[numpts] = s[numpts-1] + vik_coord_diff ( &(VIK_TRACKPOINT(iter->prev->data)->coord), &(VIK_TRACKPOINT(iter->data)->coord) );
t[numpts] = VIK_TRACKPOINT(iter->data)->timestamp;
numpts++;
iter = iter->next;
}
// Iterate through a portion of the track to get an average speed for that part
// This will essentially interpolate between segments, which I think is right given the usage of 'get_length_including_gaps'
index = 0; /* index of the current trackpoint. */
for (i = 0; i < num_chunks; i++) {
// Similar to the make_speed_map, but instead of using a time chunk, use a distance chunk
if (s[0] + i*chunk_length >= s[index]) {
gdouble acc_t = 0, acc_s = 0;
while (s[0] + i*chunk_length >= s[index]) {
acc_s += (s[index+1]-s[index]);
acc_t += (t[index+1]-t[index]);
index++;
}
v[i] = acc_s/acc_t;
}
else if (i) {
v[i] = v[i-1];
}
else {
v[i] = 0;
}
}
g_free(s);
g_free(t);
return v;
}
/* by Alex Foobarian */
VikTrackpoint *vik_track_get_closest_tp_by_percentage_dist ( VikTrack *tr, gdouble reldist, gdouble *meters_from_start )
{
gdouble dist = vik_track_get_length_including_gaps(tr) * reldist;
gdouble current_dist = 0.0;
gdouble current_inc = 0.0;
if ( tr->trackpoints )
{
GList *iter = tr->trackpoints->next;
GList *last_iter = NULL;
gdouble last_dist = 0.0;
while (iter)
{
current_inc = vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord),
&(VIK_TRACKPOINT(iter->prev->data)->coord) );
last_dist = current_dist;
current_dist += current_inc;
if ( current_dist >= dist )
break;
last_iter = iter;
iter = iter->next;
}
if (!iter) { /* passing the end the track */
if (last_iter) {
if (meters_from_start)
*meters_from_start = last_dist;
return(VIK_TRACKPOINT(last_iter->data));
}
else
return NULL;
}
/* we've gone past the dist already, was prev trackpoint closer? */
/* should do a vik_coord_average_weighted() thingy. */
if ( iter->prev && abs(current_dist-current_inc-dist) < abs(current_dist-dist) ) {
if (meters_from_start)
*meters_from_start = last_dist;
iter = iter->prev;
}
else
if (meters_from_start)
*meters_from_start = current_dist;
return VIK_TRACKPOINT(iter->data);
}
return NULL;
}
VikTrackpoint *vik_track_get_closest_tp_by_percentage_time ( VikTrack *tr, gdouble reltime, time_t *seconds_from_start )
{
time_t t_pos, t_start, t_end, t_total;
t_start = VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
t_end = VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->timestamp;
t_total = t_end - t_start;
t_pos = t_start + t_total * reltime;
if ( !tr->trackpoints )
return NULL;
GList *iter = tr->trackpoints;
while (iter) {
if (VIK_TRACKPOINT(iter->data)->timestamp == t_pos)
break;
if (VIK_TRACKPOINT(iter->data)->timestamp > t_pos) {
if (iter->prev == NULL) /* first trackpoint */
break;
time_t t_before = t_pos - VIK_TRACKPOINT(iter->prev)->timestamp;
time_t t_after = VIK_TRACKPOINT(iter->data)->timestamp - t_pos;
if (t_before <= t_after)
iter = iter->prev;
break;
}
else if ((iter->next == NULL) && (t_pos < (VIK_TRACKPOINT(iter->data)->timestamp + 3))) /* last trackpoint: accommodate for round-off */
break;
iter = iter->next;
}
if (!iter)
return NULL;
if (seconds_from_start)
*seconds_from_start = VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(tr->trackpoints->data)->timestamp;
return VIK_TRACKPOINT(iter->data);
}
VikTrackpoint* vik_track_get_tp_by_max_speed ( const VikTrack *tr )
{
gdouble maxspeed = 0.0, speed = 0.0;
if ( !tr->trackpoints )
return NULL;
GList *iter = tr->trackpoints;
VikTrackpoint *max_speed_tp = NULL;
while (iter) {
if (iter->prev) {
if ( VIK_TRACKPOINT(iter->data)->has_timestamp &&
VIK_TRACKPOINT(iter->prev->data)->has_timestamp &&
(! VIK_TRACKPOINT(iter->data)->newsegment) ) {
speed = vik_coord_diff ( &(VIK_TRACKPOINT(iter->data)->coord), &(VIK_TRACKPOINT(iter->prev->data)->coord) )
/ ABS(VIK_TRACKPOINT(iter->data)->timestamp - VIK_TRACKPOINT(iter->prev->data)->timestamp);
if ( speed > maxspeed ) {
maxspeed = speed;
max_speed_tp = VIK_TRACKPOINT(iter->data);
}
}
}
iter = iter->next;
}
if (!max_speed_tp)
return NULL;
return max_speed_tp;
}
VikTrackpoint* vik_track_get_tp_by_max_alt ( const VikTrack *tr )
{
gdouble maxalt = -5000.0;
if ( !tr->trackpoints )
return NULL;
GList *iter = tr->trackpoints;
VikTrackpoint *max_alt_tp = NULL;
while (iter) {
if ( VIK_TRACKPOINT(iter->data)->altitude > maxalt ) {
maxalt = VIK_TRACKPOINT(iter->data)->altitude;
max_alt_tp = VIK_TRACKPOINT(iter->data);
}
iter = iter->next;
}
if (!max_alt_tp)
return NULL;
return max_alt_tp;
}
VikTrackpoint* vik_track_get_tp_by_min_alt ( const VikTrack *tr )
{
gdouble minalt = 25000.0;
if ( !tr->trackpoints )
return NULL;
GList *iter = tr->trackpoints;
VikTrackpoint *min_alt_tp = NULL;
while (iter) {
if ( VIK_TRACKPOINT(iter->data)->altitude < minalt ) {
minalt = VIK_TRACKPOINT(iter->data)->altitude;
min_alt_tp = VIK_TRACKPOINT(iter->data);
}
iter = iter->next;
}
if (!min_alt_tp)
return NULL;
return min_alt_tp;
}
gboolean vik_track_get_minmax_alt ( const VikTrack *tr, gdouble *min_alt, gdouble *max_alt )
{
*min_alt = 25000;
*max_alt = -5000;
if ( tr && tr->trackpoints && tr->trackpoints->data && (VIK_TRACKPOINT(tr->trackpoints->data)->altitude != VIK_DEFAULT_ALTITUDE) ) {
GList *iter = tr->trackpoints->next;
gdouble tmp_alt;
while (iter)
{
tmp_alt = VIK_TRACKPOINT(iter->data)->altitude;
if ( tmp_alt > *max_alt )
*max_alt = tmp_alt;
if ( tmp_alt < *min_alt )
*min_alt = tmp_alt;
iter = iter->next;
}
return TRUE;
}
return FALSE;
}
void vik_track_marshall ( VikTrack *tr, guint8 **data, guint *datalen)
{
GList *tps;
GByteArray *b = g_byte_array_new();
guint len;
guint intp, ntp;
g_byte_array_append(b, (guint8 *)tr, sizeof(*tr));
/* we'll fill out number of trackpoints later */
intp = b->len;
g_byte_array_append(b, (guint8 *)&len, sizeof(len));
tps = tr->trackpoints;
ntp = 0;
while (tps) {
g_byte_array_append(b, (guint8 *)tps->data, sizeof(VikTrackpoint));
tps = tps->next;
ntp++;
}
*(guint *)(b->data + intp) = ntp;
len = (tr->comment) ? strlen(tr->comment)+1 : 0;
g_byte_array_append(b, (guint8 *)&len, sizeof(len));
if (tr->comment) g_byte_array_append(b, (guint8 *)tr->comment, len);
*data = b->data;
*datalen = b->len;
g_byte_array_free(b, FALSE);
}
VikTrack *vik_track_unmarshall (guint8 *data, guint datalen)
{
guint len;
VikTrack *new_tr = vik_track_new();
VikTrackpoint *new_tp;
guint ntp;
gint i;
/* only the visibility is needed */
new_tr->visible = ((VikTrack *)data)->visible;
data += sizeof(*new_tr);
ntp = *(guint *)data;
data += sizeof(ntp);
for (i=0; i<ntp; i++) {
new_tp = vik_trackpoint_new();
memcpy(new_tp, data, sizeof(*new_tp));
data += sizeof(*new_tp);
new_tr->trackpoints = g_list_append(new_tr->trackpoints, new_tp);
}
len = *(guint *)data;
data += sizeof(len);
if (len) {
new_tr->comment = g_strdup((gchar *)data);
}
return new_tr;
}
void vik_track_apply_dem_data ( VikTrack *tr )
{
GList *tp_iter;
gint16 elev;
tp_iter = tr->trackpoints;
while ( tp_iter ) {
/* TODO: of the 4 possible choices we have for choosing an elevation
* (trackpoint in between samples), choose the one with the least elevation change
* as the last */
elev = a_dems_get_elev_by_coord ( &(VIK_TRACKPOINT(tp_iter->data)->coord), VIK_DEM_INTERPOL_BEST );
if ( elev != VIK_DEM_INVALID_ELEVATION )
VIK_TRACKPOINT(tp_iter->data)->altitude = elev;
tp_iter = tp_iter->next;
}
}
/*
* Apply DEM data (if available) - to only the last trackpoint
*/
void vik_track_apply_dem_data_last_trackpoint ( VikTrack *tr )
{
gint16 elev;
if ( tr->trackpoints ) {
/* As in vik_track_apply_dem_data above - use 'best' interpolation method */
elev = a_dems_get_elev_by_coord ( &(VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->coord), VIK_DEM_INTERPOL_BEST );
if ( elev != VIK_DEM_INVALID_ELEVATION )
VIK_TRACKPOINT(g_list_last(tr->trackpoints)->data)->altitude = elev;
}
}
/* appends t2 to t1, leaving t2 with no trackpoints */
void vik_track_steal_and_append_trackpoints ( VikTrack *t1, VikTrack *t2 )
{
if ( t1->trackpoints ) {
GList *tpiter = t1->trackpoints;
while ( tpiter->next )
tpiter = tpiter->next;
tpiter->next = t2->trackpoints;
t2->trackpoints->prev = tpiter;
} else
t1->trackpoints = t2->trackpoints;
t2->trackpoints = NULL;
}
/* starting at the end, looks backwards for the last "double point", a duplicate trackpoint.
* If there is no double point, deletes all the trackpoints.
* Returns the new end of the track (or the start if there are no double points)
*/
VikCoord *vik_track_cut_back_to_double_point ( VikTrack *tr )
{
GList *iter = tr->trackpoints;
VikCoord *rv;
if ( !iter )
return NULL;
while ( iter->next )
iter = iter->next;
while ( iter->prev ) {
if ( vik_coord_equals((VikCoord *)iter->data, (VikCoord *)iter->prev->data) ) {
GList *prev = iter->prev;
rv = g_malloc(sizeof(VikCoord));
*rv = *((VikCoord *) iter->data);
/* truncate trackpoint list */
iter->prev = NULL; /* pretend it's the end */
g_list_foreach ( iter, (GFunc) g_free, NULL );
g_list_free( iter );
prev->next = NULL;
return rv;
}
iter = iter->prev;
}
/* no double point found! */
rv = g_malloc(sizeof(VikCoord));
*rv = *((VikCoord *) tr->trackpoints->data);
g_list_foreach ( tr->trackpoints, (GFunc) g_free, NULL );
g_list_free( tr->trackpoints );
tr->trackpoints = NULL;
return rv;
}