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-rw-r--r--src/mbgl/util/geometry_within.cpp143
1 files changed, 0 insertions, 143 deletions
diff --git a/src/mbgl/util/geometry_within.cpp b/src/mbgl/util/geometry_within.cpp
deleted file mode 100644
index 618567a8e1..0000000000
--- a/src/mbgl/util/geometry_within.cpp
+++ /dev/null
@@ -1,143 +0,0 @@
-#include <mbgl/util/geometry_within.hpp>
-
-#include <algorithm>
-
-namespace mbgl {
-
-namespace {
-bool rayIntersect(const Point<int64_t>& p, const Point<int64_t>& p1, const Point<int64_t>& p2) {
- return ((p1.y > p.y) != (p2.y > p.y)) && (p.x < (p2.x - p1.x) * (p.y - p1.y) / (p2.y - p1.y) + p1.x);
-}
-
-// check if point p in on line segment with end points p1 and p2
-bool onBoundary(const Point<int64_t>& p, const Point<int64_t>& p1, const Point<int64_t>& p2) {
- // requirements of point p on line segment:
- // 1. colinear: cross product of vector p->p1(x1, y1) and vector p->p2(x2, y2) equals to 0
- // 2. p is between p1 and p2
- const auto x1 = p.x - p1.x;
- const auto y1 = p.y - p1.y;
- const auto x2 = p.x - p2.x;
- const auto y2 = p.y - p2.y;
- return (x1 * y2 - x2 * y1 == 0) && (x1 * x2 <= 0) && (y1 * y2 <= 0);
-}
-
-// a, b are end points for line segment1, c and d are end points for line segment2
-bool lineIntersectLine(const Point<int64_t>& a,
- const Point<int64_t>& b,
- const Point<int64_t>& c,
- const Point<int64_t>& d) {
- const auto perp = [](const Point<int64_t>& v1, const Point<int64_t>& v2) { return (v1.x * v2.y - v1.y * v2.x); };
-
- // check if two segments are parallel or not
- // precondition is end point a, b is inside polygon, if line a->b is
- // parallel to polygon edge c->d, then a->b won't intersect with c->d
- auto vectorP = Point<int64_t>(b.x - a.x, b.y - a.y);
- auto vectorQ = Point<int64_t>(d.x - c.x, d.y - c.y);
- if (perp(vectorQ, vectorP) == 0) return false;
-
- // check if p1 and p2 are in different sides of line segment q1->q2
- const auto twoSided =
- [](const Point<int64_t>& p1, const Point<int64_t>& p2, const Point<int64_t>& q1, const Point<int64_t>& q2) {
- int64_t x1;
- int64_t y1;
- int64_t x2;
- int64_t y2;
- int64_t x3;
- int64_t y3;
-
- // q1->p1 (x1, y1), q1->p2 (x2, y2), q1->q2 (x3, y3)
- x1 = p1.x - q1.x;
- y1 = p1.y - q1.y;
- x2 = p2.x - q1.x;
- y2 = p2.y - q1.y;
- x3 = q2.x - q1.x;
- y3 = q2.y - q1.y;
- auto ret1 = (x1 * y3 - x3 * y1);
- auto ret2 = (x2 * y3 - x3 * y2);
- return (ret1 > 0 && ret2 < 0) || (ret1 < 0 && ret2 > 0);
- };
-
- // If lines are intersecting with each other, the relative location should be:
- // a and b lie in different sides of segment c->d
- // c and d lie in different sides of segment a->b
- return twoSided(a, b, c, d) && twoSided(c, d, a, b);
-}
-
-bool lineIntersectPolygon(const Point<int64_t>& p1, const Point<int64_t>& p2, const Polygon<int64_t>& polygon) {
- for (auto ring : polygon) {
- auto length = ring.size();
- // loop through every edge of the ring
- for (std::size_t i = 0; i < length - 1; ++i) {
- if (lineIntersectLine(p1, p2, ring[i], ring[i + 1])) {
- return true;
- }
- }
- }
- return false;
-}
-
-} // namespace
-
-void updateBBox(WithinBBox& bbox, const Point<int64_t>& p) {
- bbox[0] = std::min(p.x, bbox[0]);
- bbox[1] = std::min(p.y, bbox[1]);
- bbox[2] = std::max(p.x, bbox[2]);
- bbox[3] = std::max(p.y, bbox[3]);
-}
-
-bool boxWithinBox(const WithinBBox& bbox1, const WithinBBox& bbox2) {
- if (bbox1[0] <= bbox2[0]) return false;
- if (bbox1[2] >= bbox2[2]) return false;
- if (bbox1[1] <= bbox2[1]) return false;
- if (bbox1[3] >= bbox2[3]) return false;
- return true;
-}
-
-// ray casting algorithm for detecting if point is in polygon
-bool pointWithinPolygon(const Point<int64_t>& point, const Polygon<int64_t>& polygon) {
- bool within = false;
- for (const auto& ring : polygon) {
- const auto length = ring.size();
- // loop through every edge of the ring
- for (std::size_t i = 0; i < length - 1; ++i) {
- if (onBoundary(point, ring[i], ring[i + 1])) return false;
- if (rayIntersect(point, ring[i], ring[i + 1])) {
- within = !within;
- }
- }
- }
- return within;
-}
-
-bool pointWithinPolygons(const Point<int64_t>& point, const MultiPolygon<int64_t>& polygons) {
- for (const auto& polygon : polygons) {
- if (pointWithinPolygon(point, polygon)) return true;
- }
- return false;
-}
-
-bool lineStringWithinPolygon(const LineString<int64_t>& line, const Polygon<int64_t>& polygon) {
- const auto length = line.size();
- // First, check if geometry points of line segments are all inside polygon
- for (std::size_t i = 0; i < length; ++i) {
- if (!pointWithinPolygon(line[i], polygon)) {
- return false;
- }
- }
-
- // Second, check if there is line segment intersecting polygon edge
- for (std::size_t i = 0; i < length - 1; ++i) {
- if (lineIntersectPolygon(line[i], line[i + 1], polygon)) {
- return false;
- }
- }
- return true;
-}
-
-bool lineStringWithinPolygons(const LineString<int64_t>& line, const MultiPolygon<int64_t>& polygons) {
- for (const auto& polygon : polygons) {
- if (lineStringWithinPolygon(line, polygon)) return true;
- }
- return false;
-}
-} // namespace mbgl