summaryrefslogtreecommitdiff
path: root/deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp
diff options
context:
space:
mode:
Diffstat (limited to 'deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp')
-rw-r--r--deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp251
1 files changed, 251 insertions, 0 deletions
diff --git a/deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp b/deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp
new file mode 100644
index 0000000000..212e2979d0
--- /dev/null
+++ b/deps/geojsonvt/6.3.0/include/mapbox/geojsonvt/clip.hpp
@@ -0,0 +1,251 @@
+#pragma once
+
+#include <mapbox/geojsonvt/types.hpp>
+
+namespace mapbox {
+namespace geojsonvt {
+namespace detail {
+
+template <uint8_t I>
+class clipper {
+public:
+ const double k1;
+ const double k2;
+
+ vt_geometry operator()(const vt_point& point) const {
+ return point;
+ }
+
+ vt_geometry operator()(const vt_multi_point& points) const {
+ vt_multi_point part;
+ for (const auto& p : points) {
+ const double ak = get<I>(p);
+ if (ak >= k1 && ak <= k2)
+ part.push_back(p);
+ }
+ return part;
+ }
+
+ vt_geometry operator()(const vt_line_string& line) const {
+ vt_multi_line_string parts;
+ clipLine(line, parts);
+ if (parts.size() == 1)
+ return parts[0];
+ else
+ return parts;
+ }
+
+ vt_geometry operator()(const vt_multi_line_string& lines) const {
+ vt_multi_line_string parts;
+ for (const auto& line : lines) {
+ clipLine(line, parts);
+ }
+ if (parts.size() == 1)
+ return parts[0];
+ else
+ return parts;
+ }
+
+ vt_geometry operator()(const vt_polygon& polygon) const {
+ vt_polygon result;
+ for (const auto& ring : polygon) {
+ const auto new_ring = clipRing(ring);
+ if (!new_ring.empty())
+ result.push_back(new_ring);
+ }
+ return result;
+ }
+
+ vt_geometry operator()(const vt_multi_polygon& polygons) const {
+ vt_multi_polygon result;
+ for (const auto& polygon : polygons) {
+ vt_polygon p;
+ for (const auto& ring : polygon) {
+ const auto new_ring = clipRing(ring);
+ if (!new_ring.empty())
+ p.push_back(new_ring);
+ }
+ if (!p.empty())
+ result.push_back(p);
+ }
+ return result;
+ }
+
+ vt_geometry operator()(const vt_geometry_collection& geometries) const {
+ vt_geometry_collection result;
+ for (const auto& geometry : geometries) {
+ vt_geometry::visit(geometry,
+ [&](const auto& g) { result.push_back(this->operator()(g)); });
+ }
+ return result;
+ }
+
+private:
+ vt_line_string newSlice(vt_multi_line_string& parts, vt_line_string& slice, double dist) const {
+ if (!slice.empty()) {
+ slice.dist = dist;
+ parts.push_back(std::move(slice));
+ }
+ return {};
+ }
+
+ void clipLine(const vt_line_string& line, vt_multi_line_string& slices) const {
+
+ const double dist = line.dist;
+ const size_t len = line.size();
+
+ if (len < 2)
+ return;
+
+ vt_line_string slice;
+
+ for (size_t i = 0; i < (len - 1); ++i) {
+ const auto& a = line[i];
+ const auto& b = line[i + 1];
+ const double ak = get<I>(a);
+ const double bk = get<I>(b);
+
+ if (ak < k1) {
+ if (bk > k2) { // ---|-----|-->
+ slice.push_back(intersect<I>(a, b, k1));
+ slice.push_back(intersect<I>(a, b, k2));
+ slice = newSlice(slices, slice, dist);
+
+ } else if (bk >= k1) { // ---|--> |
+ slice.push_back(intersect<I>(a, b, k1));
+ if (i == len - 2)
+ slice.push_back(b); // last point
+ }
+ } else if (ak > k2) {
+ if (bk < k1) { // <--|-----|---
+ slice.push_back(intersect<I>(a, b, k2));
+ slice.push_back(intersect<I>(a, b, k1));
+ slice = newSlice(slices, slice, dist);
+
+ } else if (bk <= k2) { // | <--|---
+ slice.push_back(intersect<I>(a, b, k2));
+ if (i == len - 2)
+ slice.push_back(b); // last point
+ }
+ } else {
+ slice.push_back(a);
+
+ if (bk < k1) { // <--|--- |
+ slice.push_back(intersect<I>(a, b, k1));
+ slice = newSlice(slices, slice, dist);
+
+ } else if (bk > k2) { // | ---|-->
+ slice.push_back(intersect<I>(a, b, k2));
+ slice = newSlice(slices, slice, dist);
+
+ } else if (i == len - 2) { // | --> |
+ slice.push_back(b);
+ }
+ }
+ }
+
+ // add the final slice
+ newSlice(slices, slice, dist);
+ }
+
+ vt_linear_ring clipRing(const vt_linear_ring& ring) const {
+ const size_t len = ring.size();
+
+ vt_linear_ring slice;
+ slice.area = ring.area;
+
+ if (len < 2)
+ return slice;
+
+ for (size_t i = 0; i < (len - 1); ++i) {
+ const auto& a = ring[i];
+ const auto& b = ring[i + 1];
+ const double ak = get<I>(a);
+ const double bk = get<I>(b);
+
+ if (ak < k1) {
+ if (bk >= k1) {
+ slice.push_back(intersect<I>(a, b, k1)); // ---|--> |
+ if (bk > k2) // ---|-----|-->
+ slice.push_back(intersect<I>(a, b, k2));
+ else if (i == len - 2)
+ slice.push_back(b); // last point
+ }
+ } else if (ak > k2) {
+ if (bk <= k2) { // | <--|---
+ slice.push_back(intersect<I>(a, b, k2));
+ if (bk < k1) // <--|-----|---
+ slice.push_back(intersect<I>(a, b, k1));
+ else if (i == len - 2)
+ slice.push_back(b); // last point
+ }
+ } else {
+ slice.push_back(a);
+ if (bk < k1) // <--|--- |
+ slice.push_back(intersect<I>(a, b, k1));
+ else if (bk > k2) // | ---|-->
+ slice.push_back(intersect<I>(a, b, k2));
+ // | --> |
+ }
+ }
+
+ // close the polygon if its endpoints are not the same after clipping
+ if (!slice.empty()) {
+ const auto& first = slice.front();
+ const auto& last = slice.back();
+ if (first != last) {
+ slice.push_back(first);
+ }
+ }
+
+ return slice;
+ }
+};
+
+/* clip features between two axis-parallel lines:
+ * | |
+ * ___|___ | /
+ * / | \____|____/
+ * | |
+ */
+
+template <uint8_t I>
+inline vt_features clip(const vt_features& features,
+ const double k1,
+ const double k2,
+ const double minAll,
+ const double maxAll) {
+
+ if (minAll >= k1 && maxAll <= k2) // trivial accept
+ return features;
+
+ if (minAll > k2 || maxAll < k1) // trivial reject
+ return {};
+
+ vt_features clipped;
+
+ for (const auto& feature : features) {
+ const auto& geom = feature.geometry;
+ const auto& props = feature.properties;
+ const auto& id = feature.id;
+
+ const double min = get<I>(feature.bbox.min);
+ const double max = get<I>(feature.bbox.max);
+
+ if (min >= k1 && max <= k2) { // trivial accept
+ clipped.push_back(feature);
+
+ } else if (min > k2 || max < k1) { // trivial reject
+ continue;
+
+ } else {
+ clipped.emplace_back(vt_geometry::visit(geom, clipper<I>{ k1, k2 }), props, id);
+ }
+ }
+
+ return clipped;
+}
+
+} // namespace detail
+} // namespace geojsonvt
+} // namespace mapbox
View Lorry Controller Status