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-rw-r--r--debian/missing-sources/leaflet.js/geometry/PolyUtil.js55
1 files changed, 55 insertions, 0 deletions
diff --git a/debian/missing-sources/leaflet.js/geometry/PolyUtil.js b/debian/missing-sources/leaflet.js/geometry/PolyUtil.js
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+++ b/debian/missing-sources/leaflet.js/geometry/PolyUtil.js
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+import * as LineUtil from './LineUtil';
+
+/*
+ * @namespace PolyUtil
+ * Various utility functions for polygon geometries.
+ */
+
+/* @function clipPolygon(points: Point[], bounds: Bounds, round?: Boolean): Point[]
+ * Clips the polygon geometry defined by the given `points` by the given bounds (using the [Sutherland-Hodgman algorithm](https://en.wikipedia.org/wiki/Sutherland%E2%80%93Hodgman_algorithm)).
+ * Used by Leaflet to only show polygon points that are on the screen or near, increasing
+ * performance. Note that polygon points needs different algorithm for clipping
+ * than polyline, so there's a separate method for it.
+ */
+export function clipPolygon(points, bounds, round) {
+ var clippedPoints,
+ edges = [1, 4, 2, 8],
+ i, j, k,
+ a, b,
+ len, edge, p;
+
+ for (i = 0, len = points.length; i < len; i++) {
+ points[i]._code = LineUtil._getBitCode(points[i], bounds);
+ }
+
+ // for each edge (left, bottom, right, top)
+ for (k = 0; k < 4; k++) {
+ edge = edges[k];
+ clippedPoints = [];
+
+ for (i = 0, len = points.length, j = len - 1; i < len; j = i++) {
+ a = points[i];
+ b = points[j];
+
+ // if a is inside the clip window
+ if (!(a._code & edge)) {
+ // if b is outside the clip window (a->b goes out of screen)
+ if (b._code & edge) {
+ p = LineUtil._getEdgeIntersection(b, a, edge, bounds, round);
+ p._code = LineUtil._getBitCode(p, bounds);
+ clippedPoints.push(p);
+ }
+ clippedPoints.push(a);
+
+ // else if b is inside the clip window (a->b enters the screen)
+ } else if (!(b._code & edge)) {
+ p = LineUtil._getEdgeIntersection(b, a, edge, bounds, round);
+ p._code = LineUtil._getBitCode(p, bounds);
+ clippedPoints.push(p);
+ }
+ }
+ points = clippedPoints;
+ }
+
+ return points;
+}