int LabelPosition::getNumPointsInPolygon( int npol, double *xp, double *yp )
{
int a, k, count = 0;
double px, py;
// cheack each corner
for ( k = 0; k < 4; k++ )
{
px = x[k];
py = y[k];
for ( a = 0; a < 2; a++ ) // and each middle of segment
{
if ( isPointInPolygon( npol, xp, yp, px, py ) )
count++;
px = ( x[k] + x[( k+1 ) %4] ) / 2.0;
py = ( y[k] + y[( k+1 ) %4] ) / 2.0;
}
}
px = ( x[0] + x[2] ) / 2.0;
py = ( y[0] + y[2] ) / 2.0;
// and the label center
if ( isPointInPolygon( npol, xp, yp, px, py ) )
count += 4; // virtually 4 points
// TODO: count with nextFeature
return count;
}
bool Polygon::isLineInterior(const Vertex &a, const Vertex &b) const {
// Both points have to be in the polygon
if (!isPointInPolygon(a, true) || !isPointInPolygon(b, true))
return false;
// If the points are identical, the line is trivially within the polygon
if (a == b)
return true;
// Test whether the line intersects a line segment strictly (proper intersection)
for (int i = 0; i < vertexCount; i++) {
int j = (i + 1) % vertexCount;
const Vertex &vs = vertices[i];
const Vertex &ve = vertices[j];
// If the line intersects a line segment strictly (proper cross section) the line is not in the polygon
if (Line::doesIntersectProperly(a, b, vs, ve))
return false;
// If one of the two line items is on the edge and the other is to the right of the edge,
// then the line is not completely within the polygon
if (Line::isOnLineStrict(vs, ve, a) && Line::isVertexRight(vs, ve, b))
return false;
if (Line::isOnLineStrict(vs, ve, b) && Line::isVertexRight(vs, ve, a))
return false;
// If one of the two line items is on a vertex, the line traces into the polygon
if ((a == vs) && !isLineInCone(i, b, true))
return false;
if ((b == vs) && !isLineInCone(i, a, true))
return false;
}
return true;
}
bool Polygon::isLineExterior(const Vertex &a, const Vertex &b) const {
// Neither of the two points must be strictly in the polygon (on the edge is allowed)
if (isPointInPolygon(a, false) || isPointInPolygon(b, false))
return false;
// If the points are identical, the line is trivially outside of the polygon
if (a == b)
return true;
// Test whether the line intersects a line segment strictly (proper intersection)
for (int i = 0; i < vertexCount; i++) {
int j = (i + 1) % vertexCount;
const Vertex &vs = vertices[i];
const Vertex &ve = vertices[j];
// If the line intersects a line segment strictly (proper intersection), then
// the line is partially inside the polygon
if (Line::doesIntersectProperly(a, b, vs, ve))
return false;
// If one of the two line items is on the edge and the other is to the right of the edge,
// the line is not completely outside the polygon
if (Line::isOnLineStrict(vs, ve, a) && Line::isVertexLeft(vs, ve, b))
return false;
if (Line::isOnLineStrict(vs, ve, b) && Line::isVertexLeft(vs, ve, a))
return false;
// If one of the lwo line items is on a vertex, the line must not run into the polygon
if ((a == vs) && isLineInCone(i, b, false))
return false;
if ((b == vs) && isLineInCone(i, a, false))
return false;
// If the vertex with start and end point is collinear, (a vs) and (b, vs) is not in the polygon
if (Line::isOnLine(a, b, vs)) {
if (isLineInCone(i, a, false))
return false;
if (isLineInCone(i, b, false))
return false;
}
}
return true;
}
/// Tries to find point in polygon.
static bool findPointInPolygon(const std::vector<Vector2> &contour, Vector2 &point) {
Rectangle bounds;
bounds.expand(contour);
auto length = contour.size();
int limit = 8;
Vector2 a, b; // Current edge.
if (contour.size()==3) {
point = Vector2((contour[0].x + contour[1].x + contour[2].x)/3,
(contour[0].y + contour[1].y + contour[2].y)/3);
return true;
}
for (std::size_t i = 0; i < length; i++) {
a = contour[i];
b = contour[(i + 1)%length];
double cx = (a.x + b.x)/2;
double cy = (a.y + b.y)/2;
double dx = (b.y - a.y)/1.374;
double dy = (a.x - b.x)/1.374;
for (int j = 1; j <= limit; j++) {
// Search to the right of the segment.
point.x = cx + dx/j;
point.y = cy + dy/j;
if (bounds.contains(point) && isPointInPolygon(point, contour))
return true;
// Search on the other side of the segment.
point.x = cx - dx/j;
point.y = cy - dy/j;
if (bounds.contains(point) && isPointInPolygon(point, contour))
return true;
}
}
return false;
}
int Image::indexForPoint(const Common::Point &point) const {
int index = -1;
for (uint32 i = 0; i < _polygons.size(); i++) {
if (isPointInPolygon(_polygons[i], point)) {
index = i;
}
}
return index;
}
bool isCircleInBox(const vector<cd> &points, cd target, double r) {
if (!isPointInPolygon(points, target)) {
// DEBUG;
return false;
}
/*
if (!isPointInTriangle2D(points[0], points[1], points[2], target)){
return false;
}
if (!isPointInTriangle2D(points[2], points[3], points[0], target)){
return false;
}
*/
for (int i = 0; i < 4; i++) {
int index0 = i;
int index1 = (i+1) % 4;
if (crossSegmentAndCircle(points[index0], points[index1], target, r)) {
return false;
}
}
return true;
}
int vg_draw_polygon(vector2D_t polygon[], unsigned n, unsigned long color)
{
size_t i, j;
vector2D_t min = polygon[0];
vector2D_t max = polygon[0];
for (i = 1; i < n; ++i)
{
if (polygon[i].x < min.x)
{
min.x = polygon[i].x;
}
else if (polygon[i].x > max.x)
{
max.x = polygon[i].x;
}
if (polygon[i].y < min.y)
{
min.y = polygon[i].y;
}
else if (polygon[i].y > max.y)
{
max.x = polygon[i].y;
}
}
vector2D_t point;
for (i = min.x; i < max.x; ++i)
{
for (j = min.y; j < max.y; ++j)
{
point = vectorCreate(i, j);
if (isPointInPolygon(polygon, n, point))
{
vg_set_pixel(i, j, color);
}
}
}
}
bool Polygon::isPointInPolygon(int x, int y, bool borderBelongsToPolygon) const {
return isPointInPolygon(Vertex(x, y), borderBelongsToPolygon);
}
static int nodeBelongsCountry(osm2olm* self, LCountry* country) {
//printf("Check in Country with polygon: %x\n", country->polygon);
return isPointInPolygon(self->node.lat, self->node.lon, country->polygon);
}