void plot(double lon1, double lat1, double lon2, double lat2,
int line_color, int text_color, double factor, const char *unit)
{
double distance;
double text_x, text_y;
double a, e2;
int nsteps = 1000;
int i;
/* establish the current graphics window */
D_setup(0);
G_get_ellipsoid_parameters(&a, &e2);
G_begin_geodesic_distance(a, e2);
D_use_color(line_color);
G_shortest_way(&lon1, &lon2);
if (lon1 != lon2) {
G_begin_geodesic_equation(lon1, lat1, lon2, lat2);
D_begin();
for (i = 0; i <= nsteps; i++) {
double lon = lon1 + (lon2 - lon1) * i / nsteps;
double lat = G_geodesic_lat_from_lon(lon);
if (i == 0)
D_move_abs(lon, lat);
else
D_cont_abs(lon, lat);
}
D_end();
D_stroke();
text_x = (lon1 + lon2) / 2;
text_y = G_geodesic_lat_from_lon(text_x);
}
else {
D_line_abs(lon1, lat1, lon2, lat2);
text_x = (lon1 + lon2) / 2;
text_y = (lat1 + lat2) / 2;
}
if (text_color != -1) {
double t, b, l, r;
char buf[100];
D_text_size(10, 10);
distance = G_geodesic_distance(lon1, lat1, lon2, lat2);
sprintf(buf, "%.0f %s", distance / factor, unit);
D_pos_abs(text_x, text_y);
D_get_text_box(buf, &t, &b, &l, &r);
if (t - D_get_u_north() > 0)
text_y -= t - D_get_u_north();
if (b - D_get_u_south() < 0)
text_y -= b - D_get_u_south();
if (r - D_get_u_east() > 0)
text_x -= r - D_get_u_east();
if (l - D_get_u_west() < 0)
text_x -= l - D_get_u_west();
D_use_color(text_color);
D_pos_abs(text_x, text_y);
D_text(buf);
}
}
int draw_line(int ltype, int line,
const struct line_pnts *Points, const struct line_cats *Cats,
int chcat, double size, int default_width,
const struct cat_list *Clist, SYMBOL * Symb,
RGBA_Color * primary_color,
int *n_points, int *n_lines, int *n_centroids,
int *n_boundaries, int *n_faces, RGBA_Color *secondary_color)
{
double var_size, rotation;
int i;
double x0, y0;
double *x, *y;
int found, cat;
rotation = 0.0;
var_size = size;
cat = -1;
if (!ltype)
return 0;
if (Points->n_points == 0)
return 0;
found = FALSE;
if (chcat) {
for (i = 0; i < Cats->n_cats; i++) {
if (Cats->field[i] == Clist->field &&
Vect_cat_in_cat_list(Cats->cat[i], Clist)) {
found = TRUE;
break;
}
}
if (!found)
return 0;
}
else if (Clist->field > 0) {
for (i = 0; i < Cats->n_cats; i++) {
if (Cats->field[i] == Clist->field) {
found = TRUE;
break;
}
}
/* lines with no category will be displayed */
if (Cats->n_cats > 0 && !found)
return 0;
}
G_debug(3, "\tdisplay feature %d, cat %d", line, cat);
/* enough of the prep work, lets start plotting stuff */
x = Points->x;
y = Points->y;
if ((ltype & GV_POINTS)) {
x0 = x[0];
y0 = y[0];
/* skip if the point is outside of the display window */
/* xy < 0 tests make it go ever-so-slightly faster */
if (x0 > D_get_u_east() || x0 < D_get_u_west() ||
y0 < D_get_u_south() || y0 > D_get_u_north())
return 0;
D_line_width(default_width);
D_symbol2(Symb, x0, y0, primary_color, secondary_color);
}
else {
/* Plot the lines */
D_line_width(default_width);
D_RGB_color(primary_color->r, primary_color->g, primary_color->b);
if (Points->n_points == 1) /* line with one coor */
D_polydots_abs(x, y, Points->n_points);
else /* use different user defined render methods */
D_polyline_abs(x, y, Points->n_points);
}
switch (ltype) {
case GV_POINT:
(*n_points)++;
break;
case GV_LINE:
(*n_lines)++;
break;
case GV_CENTROID:
(*n_centroids)++;
break;
case GV_BOUNDARY:
(*n_boundaries)++;
break;
case GV_FACE:
(*n_faces)++;
break;
default:
break;
}
return 1;
}
