/*!
\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);
}
/*!
\brief Check if segment intersect vector region
Clipping performed:
- bgn and end are replaced so that both points are within viewregion
- if seg intersects
\param gs surface (geosurf)
\param bgn begin point
\param end end point
\return 0 if segment doesn't intersect the viewregion, or intersects only at corner
\return otherwise returns 1
*/
int seg_intersect_vregion(geosurf * gs, float *bgn, float *end)
{
float *replace, xl, yb, xr, yt, xi, yi;
int inside = 0;
xl = 0.0;
xr = VCOL2X(gs, VCOLS(gs));
yt = VROW2Y(gs, 0);
yb = VROW2Y(gs, VROWS(gs));
if (in_vregion(gs, bgn)) {
replace = end;
inside++;
}
if (in_vregion(gs, end)) {
replace = bgn;
inside++;
}
if (inside == 2) {
return (1);
}
else if (inside) {
/* one in & one out - replace gets first intersection */
if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yb, xl, yt, &xi, &yi)) {
/* left */
}
else if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xr, yb, xr, yt, &xi, &yi)) {
/* right */
}
else if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yb, xr, yb, &xi, &yi)) {
/* bottom */
}
else if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yt, xr, yt, &xi, &yi)) {
/* top */
}
replace[X] = xi;
replace[Y] = yi;
}
else {
/* both out - find 2 intersects & replace both */
float pt1[2], pt2[2];
replace = pt1;
if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yb, xl, yt, &xi, &yi)) {
replace[X] = xi;
replace[Y] = yi;
replace = pt2;
inside++;
}
if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xr, yb, xr, yt, &xi, &yi)) {
replace[X] = xi;
replace[Y] = yi;
replace = pt2;
inside++;
}
if (inside < 2) {
if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yb, xr, yb, &xi, &yi)) {
replace[X] = xi;
replace[Y] = yi;
replace = pt2;
inside++;
}
}
if (inside < 2) {
if (segs_intersect
(bgn[X], bgn[Y], end[X], end[Y], xl, yt, xr, yt, &xi, &yi)) {
replace[X] = xi;
replace[Y] = yi;
inside++;
}
}
if (inside < 2) {
return (0); /* no intersect or only 1 point on corner */
}
/* compare dist of intersects to bgn - closest replaces bgn */
if (GS_P2distance(bgn, pt1) < GS_P2distance(bgn, pt2)) {
bgn[X] = pt1[X];
bgn[Y] = pt1[Y];
end[X] = pt2[X];
end[Y] = pt2[Y];
}
else {
bgn[X] = pt2[X];
bgn[Y] = pt2[Y];
end[X] = pt1[X];
end[Y] = pt1[Y];
}
}
return (1);
}
