/*!
\brief Calculate distance on surface
\param gs pointer to geosurf struct
\param p1 from point
\param p2 to point
\param[out] dist distnace
\param use_exag use exag for calculation
\return 0 on error (points not in region)
\return 1 on success
*/
int gs_distance_onsurf(geosurf * gs, float *p1, float *p2, float *dist,
int use_exag)
{
Point3 *tmp;
int np, i;
float exag, length;
if (in_vregion(gs, p1) && in_vregion(gs, p2)) {
if (NULL == (tmp = gsdrape_get_segments(gs, p1, p2, &np))) {
return (0);
}
length = 0.;
if (use_exag) {
exag = GS_global_exag();
tmp[0][Z] *= exag;
for (i = 0; i < (np - 1); i++) {
tmp[i + 1][Z] *= exag;
length += GS_distance(tmp[i], tmp[i + 1]);
}
}
else {
for (i = 0; i < (np - 1); i++) {
length += GS_distance(tmp[i], tmp[i + 1]);
}
}
*dist = length;
return (1);
}
return (0);
}
/*!
\brief Get line width
\param gln line (geoline)
\return line width
*/
float gv_line_length(geoline * gln)
{
int n;
float length = 0.0;
for (n = 0; n < gln->npts - 1; n++) {
if (gln->p2) {
length += GS_P2distance(gln->p2[n + 1], gln->p2[n]);
}
else {
length += GS_distance(gln->p3[n + 1], gln->p3[n]);
}
}
return (length);
}
int Nviz_set_cplane_here(nv_data *data, int cplane, float sx, float sy)
{
float x, y, z, len, los[2][3];
float dx, dy, dz;
float n, s, w, e;
Point3 realto, dir;
int id;
geosurf *gs;
if (GS_get_selected_point_on_surface(sx, sy, &id, &x, &y, &z)) {
gs = gs_get_surf(id);
if (gs) {
realto[X] = x - gs->ox + gs->x_trans;
realto[Y] = y - gs->oy + gs->y_trans;
realto[Z] = z + gs->z_trans;
}
else
return 0;
}
else {
if (gsd_get_los(los, (short)sx, (short)sy)) {
len = GS_distance(Gv.from_to[FROM], Gv.real_to);
GS_v3dir(los[FROM], los[TO], dir);
GS_v3mult(dir, len);
realto[X] = Gv.from_to[FROM][X] + dir[X];
realto[Y] = Gv.from_to[FROM][Y] + dir[Y];
realto[Z] = Gv.from_to[FROM][Z] + dir[Z];
}
else
return 0;
}
Nviz_get_cplane_translation(data, cplane, &dx, &dy, &dz);
GS_get_region(&n, &s, &w, &e);
dx = realto[X] - (e - w) / 2.;
dy = realto[Y] - (n - s) / 2.;
Nviz_set_cplane_translation(data, cplane, dx, dy, dz);
return 1;
}
/*!
\brief ADD
\param gv view (geoview)
\return ?
*/
int gsd_zup_twist(geoview * gv)
{
float fr_to[2][4];
float look_theta, pi;
float alpha, beta;
float zup[3], yup[3], zupmag, yupmag;
pi = 4.0 * atan(1.0);
/* *************************************************************** */
/* This block of code is used to keep pos z in the up direction,
* correcting for SGI system default which is pos y in the up
* direction. Involves finding up vectors for both y up and
* z up, then determining angle between them. LatLon mode uses y as
* up direction instead of z, so no correction necessary. Next rewrite,
* we should use y as up for all drawing.
*/
GS_v3eq(fr_to[FROM], gv->from_to[FROM]);
GS_v3eq(fr_to[TO], gv->from_to[TO]);
/* neg alpha OK since sin(-x) = -sin(x) */
alpha = pi / 2.0 - acos(fr_to[FROM][Z] - fr_to[TO][Z]);
zup[X] = fr_to[TO][X];
zup[Y] = fr_to[TO][Y];
if (sin(alpha)) {
zup[Z] = fr_to[TO][Z] + 1 / sin(alpha);
}
else {
zup[Z] = fr_to[FROM][Z] + 1.0;
}
zupmag = GS_distance(fr_to[FROM], zup);
yup[X] = fr_to[TO][X];
yup[Z] = fr_to[TO][Z];
/* neg beta OK since sin(-x) = -sin(x) */
beta = pi / 2.0 - acos(fr_to[TO][Y] - fr_to[FROM][Y]);
if (sin(beta)) {
yup[Y] = fr_to[TO][Y] - 1 / sin(beta);
}
else {
yup[Y] = fr_to[FROM][Y] + 1.0;
}
yupmag = GS_distance(fr_to[FROM], yup);
look_theta = (1800.0 / pi) *
acos(((zup[X] - fr_to[FROM][X]) * (yup[X] - fr_to[FROM][X])
+ (zup[Y] - fr_to[FROM][Y]) * (yup[Y] - fr_to[FROM][Y])
+ (zup[Z] - fr_to[FROM][Z]) * (yup[Z] - fr_to[FROM][Z])) /
(zupmag * yupmag));
if (fr_to[TO][X] - fr_to[FROM][X] < 0.0) {
look_theta = -look_theta;
}
if (fr_to[TO][Z] - fr_to[FROM][Z] < 0.0) {
/* looking down */
if (fr_to[TO][Y] - fr_to[FROM][Y] < 0.0) {
look_theta = 1800 - look_theta;
}
}
else {
/* looking up */
if (fr_to[TO][Y] - fr_to[FROM][Y] > 0.0) {
look_theta = 1800 - look_theta;
}
}
return ((int)(gv->twist + 1800 + look_theta));
}
