int msIntersectPolygons(shapeObj *p1, shapeObj *p2) {
int c1,v1,c2,v2;
/* STEP 1: polygon 1 completely contains 2 (only need to check one point from each part) */
for(c2=0; c2<p2->numlines; c2++) {
if(msIntersectPointPolygon(&(p2->line[c2].point[0]), p1) == MS_TRUE) // this considers holes and multiple parts
return(MS_TRUE);
}
/* STEP 2: polygon 2 completely contains 1 (only need to check one point from each part) */
for(c1=0; c1<p1->numlines; c1++) {
if(msIntersectPointPolygon(&(p1->line[c1].point[0]), p2) == MS_TRUE) // this considers holes and multiple parts
return(MS_TRUE);
}
/* STEP 3: look for intersecting line segments */
for(c1=0; c1<p1->numlines; c1++)
for(v1=1; v1<p1->line[c1].numpoints; v1++)
for(c2=0; c2<p2->numlines; c2++)
for(v2=1; v2<p2->line[c2].numpoints; v2++)
if(msIntersectSegments(&(p1->line[c1].point[v1-1]), &(p1->line[c1].point[v1]), &(p2->line[c2].point[v2-1]), &(p2->line[c2].point[v2])) == MS_TRUE)
return(MS_TRUE);
/*
** At this point we know there are are no intersections between edges. There may be other tests necessary
** but I haven't run into any cases that require them.
*/
return(MS_FALSE);
}
int msIntersectPolygons(shapeObj *p1, shapeObj *p2)
{
int i;
/* STEP 1: polygon 1 completely contains 2 (only need to check one point from each part) */
for(i=0; i<p2->numlines; i++) {
if(msIntersectPointPolygon(&(p2->line[i].point[0]), p1) == MS_TRUE) /* this considers holes and multiple parts */
return(MS_TRUE);
}
/* STEP 2: polygon 2 completely contains 1 (only need to check one point from each part) */
for(i=0; i<p1->numlines; i++) {
if(msIntersectPointPolygon(&(p1->line[i].point[0]), p2) == MS_TRUE) /* this considers holes and multiple parts */
return(MS_TRUE);
}
/* STEP 3: look for intersecting line segments */
if (msIntersectPolylines(p1, p2) == MS_TRUE)
return(MS_TRUE);
/*
** At this point we know there are are no intersections between edges. There may be other tests necessary
** but I haven't run into any cases that require them.
*/
return(MS_FALSE);
}
int msIntersectMultipointPolygon(multipointObj *points, shapeObj *poly) {
int i;
for(i=0; i<points->numpoints; i++) {
if(msIntersectPointPolygon(&(points->point[i]), poly) == MS_TRUE)
return(MS_TRUE);
}
return(MS_FALSE);
}
int msIntersectPolylinePolygon(shapeObj *line, shapeObj *poly) {
int i;
/* STEP 1: polygon might competely contain the polyline or one of it's parts (only need to check one point from each part) */
for(i=0; i<line->numlines; i++) {
if(msIntersectPointPolygon(&(line->line[i].point[0]), poly) == MS_TRUE) /* this considers holes and multiple parts */
return(MS_TRUE);
}
/* STEP 2: look for intersecting line segments */
if (msIntersectPolylines(line, poly) == MS_TRUE)
return (MS_TRUE);
return(MS_FALSE);
}
int msIntersectMultipointPolygon(shapeObj *multipoint, shapeObj *poly) {
int i,j;
/* The change to loop through all the lines has been made for ticket
* #2443 but is no more needed since ticket #2762. PostGIS now put all
* points into a single line. */
for(i=0; i<multipoint->numlines; i++ ) {
lineObj points = multipoint->line[i];
for(j=0; j<points.numpoints; j++) {
if(msIntersectPointPolygon(&(points.point[j]), poly) == MS_TRUE)
return(MS_TRUE);
}
}
return(MS_FALSE);
}
int msIntersectPolylinePolygon(shapeObj *line, shapeObj *poly) {
int c1,v1,c2,v2;
// STEP 1: polygon might competely contain the polyline or one of it's parts (only need to check one point from each part)
for(c1=0; c1<line->numlines; c1++) {
if(msIntersectPointPolygon(&(line->line[c1].point[0]), poly) == MS_TRUE) // this considers holes and multiple parts
return(MS_TRUE);
}
// STEP 2: look for intersecting line segments
for(c1=0; c1<line->numlines; c1++)
for(v1=1; v1<line->line[c1].numpoints; v1++)
for(c2=0; c2<poly->numlines; c2++)
for(v2=1; v2<poly->line[c2].numpoints; v2++)
if(msIntersectSegments(&(line->line[c1].point[v1-1]), &(line->line[c1].point[v1]), &(poly->line[c2].point[v2-1]), &(poly->line[c2].point[v2])) == MS_TRUE)
return(MS_TRUE);
return(MS_FALSE);
}
double msDistancePointToShape(pointObj *point, shapeObj *shape)
{
int i, j;
double dist, minDist=-1;
switch(shape->type) {
case(MS_SHAPE_POINT):
for(j=0;j<shape->numlines;j++) {
for(i=0; i<shape->line[j].numpoints; i++) {
dist = msDistancePointToPoint(point, &(shape->line[j].point[i]));
if((dist < minDist) || (minDist < 0)) minDist = dist;
}
}
break;
case(MS_SHAPE_LINE):
for(j=0;j<shape->numlines;j++) {
for(i=1; i<shape->line[j].numpoints; i++) {
dist = msDistancePointToSegment(point, &(shape->line[j].point[i-1]), &(shape->line[j].point[i]));
if((dist < minDist) || (minDist < 0)) minDist = dist;
}
}
break;
case(MS_SHAPE_POLYGON):
if(msIntersectPointPolygon(point, shape))
minDist = 0; // point is IN the shape
else { // treat shape just like a line
for(j=0;j<shape->numlines;j++) {
for(i=1; i<shape->line[j].numpoints; i++) {
dist = msDistancePointToSegment(point, &(shape->line[j].point[i-1]), &(shape->line[j].point[i]));
if((dist < minDist) || (minDist < 0)) minDist = dist;
}
}
}
break;
default:
break;
}
return(minDist);
}
double msDistanceShapeToShape(shapeObj *shape1, shapeObj *shape2)
{
int i,j,k,l;
double dist, minDist=-1;
switch(shape1->type) {
case(MS_SHAPE_POINT): // shape1
for(i=0;i<shape1->numlines;i++) {
for(j=0; j<shape1->line[i].numpoints; j++) {
dist = msDistancePointToShape(&(shape1->line[i].point[j]), shape2);
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
break;
case(MS_SHAPE_LINE): // shape1
switch(shape2->type) {
case(MS_SHAPE_POINT):
for(i=0;i<shape2->numlines;i++) {
for(j=0; j<shape2->line[i].numpoints; j++) {
dist = msDistancePointToShape(&(shape2->line[i].point[j]), shape1);
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
break;
case(MS_SHAPE_LINE):
for(i=0;i<shape1->numlines;i++) {
for(j=1; j<shape1->line[i].numpoints; j++) {
for(k=0;k<shape2->numlines;k++) {
for(l=1; l<shape2->line[k].numpoints; l++) {
// check intersection (i.e. dist=0)
if(msIntersectSegments(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l])) == MS_TRUE)
return(0);
// no intersection, compute distance
dist = msDistanceSegmentToSegment(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l]));
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
}
}
break;
case(MS_SHAPE_POLYGON):
// shape2 (the polygon) could contain shape1 or one of it's parts
for(i=0; i<shape1->numlines; i++) {
if(msIntersectPointPolygon(&(shape1->line[0].point[0]), shape2) == MS_TRUE) // this considers holes and multiple parts
return(0);
}
// check segment intersection and, if necessary, distance between segments
for(i=0;i<shape1->numlines;i++) {
for(j=1; j<shape1->line[i].numpoints; j++) {
for(k=0;k<shape2->numlines;k++) {
for(l=1; l<shape2->line[k].numpoints; l++) {
// check intersection (i.e. dist=0)
if(msIntersectSegments(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l])) == MS_TRUE)
return(0);
// no intersection, compute distance
dist = msDistanceSegmentToSegment(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l]));
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
}
}
break;
}
break;
case(MS_SHAPE_POLYGON): // shape1
switch(shape2->type) {
case(MS_SHAPE_POINT):
for(i=0;i<shape2->numlines;i++) {
for(j=0; j<shape2->line[i].numpoints; j++) {
dist = msDistancePointToShape(&(shape2->line[i].point[j]), shape1);
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
break;
case(MS_SHAPE_LINE):
// shape1 (the polygon) could contain shape2 or one of it's parts
for(i=0; i<shape2->numlines; i++) {
if(msIntersectPointPolygon(&(shape2->line[i].point[0]), shape1) == MS_TRUE) // this considers holes and multiple parts
return(0);
}
// check segment intersection and, if necessary, distance between segments
for(i=0;i<shape1->numlines;i++) {
for(j=1; j<shape1->line[i].numpoints; j++) {
for(k=0;k<shape2->numlines;k++) {
for(l=1; l<shape2->line[k].numpoints; l++) {
// check intersection (i.e. dist=0)
if(msIntersectSegments(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l])) == MS_TRUE)
return(0);
// no intersection, compute distance
dist = msDistanceSegmentToSegment(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l]));
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
}
}
break;
case(MS_SHAPE_POLYGON):
// shape1 completely contains shape2 (only need to check one point from each part)
for(i=0; i<shape2->numlines; i++) {
if(msIntersectPointPolygon(&(shape2->line[i].point[0]), shape1) == MS_TRUE) // this considers holes and multiple parts
return(0);
}
// shape2 completely contains shape1 (only need to check one point from each part)
for(i=0; i<shape1->numlines; i++) {
if(msIntersectPointPolygon(&(shape1->line[i].point[0]), shape2) == MS_TRUE) // this considers holes and multiple parts
return(0);
}
// check segment intersection and, if necessary, distance between segments
for(i=0;i<shape1->numlines;i++) {
for(j=1; j<shape1->line[i].numpoints; j++) {
for(k=0;k<shape2->numlines;k++) {
for(l=1; l<shape2->line[k].numpoints; l++) {
// check intersection (i.e. dist=0)
if(msIntersectSegments(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l])) == MS_TRUE)
return(0);
// no intersection, compute distance
dist = msDistanceSegmentToSegment(&(shape1->line[i].point[j-1]), &(shape1->line[i].point[j]), &(shape2->line[k].point[l-1]), &(shape2->line[k].point[l]));
if((dist < minDist) || (minDist < 0))
minDist = dist;
}
}
}
}
break;
}
break;
}
return(minDist);
}