Add ol.geom.flat.intersectsextent

Includes functions for testing if an extent and a geometry intersect.

test/spec/ol/geom/flat/intersectsextentflatgeom.test.js

@@ -0,0 +1,92 @@
+goog.provide('ol.test.geom.flat.intersectsextent');
+
+describe('ol.geom.flat.intersectsextent', function() {
+
+  describe('ol.geom.flat.intersectsextent.lineString', function() {
+    var flatCoordinates;
+    beforeEach(function() {
+      flatCoordinates = [0, 0, 1, 1, 2, 2];
+    });
+    describe('linestring envelope does not intersect the extent', function() {
+      it('returns false', function() {
+        var extent = [3, 3, 4, 4];
+        var r = ol.geom.flat.intersectsextent.lineString(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(false);
+      });
+    });
+    describe('linestring envelope within the extent', function() {
+      it('returns true', function() {
+        var extent = [-1, -1, 3, 3];
+        var r = ol.geom.flat.intersectsextent.lineString(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(true);
+      });
+    });
+    describe('linestring envelope bisected by an edge of the extent',
+        function() {
+          it('returns true', function() {
+            var extent = [-0.1, 0.1, 2.1, 0.1];
+            var r = ol.geom.flat.intersectsextent.lineString(
+                flatCoordinates, 0, flatCoordinates.length, 2, extent);
+            expect(r).to.be(true);
+          });
+        });
+    describe('a segment intersects the extent', function() {
+      it('returns true', function() {
+        var extent = [-0.5, -0.5, 0.5, 0.5];
+        var r = ol.geom.flat.intersectsextent.lineString(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(true);
+      });
+    });
+    describe('no segments intersect the extent', function() {
+      it('returns false', function() {
+        var extent = [0.5, 1.5, 1, 1.75];
+        var r = ol.geom.flat.intersectsextent.lineString(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(false);
+      });
+      it('returns false', function() {
+        var extent = [1, 0.25, 1.5, 0.5];
+        var r = ol.geom.flat.intersectsextent.lineString(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(false);
+      });
+    });
+  });
+
+  describe('ol.geom.flat.intersectsextent.linearRing', function() {
+    var flatCoordinates;
+    beforeEach(function() {
+      flatCoordinates = [0, 0, 1, 1, 2, 0, 1, -1, 0, 0];
+    });
+    describe('boundary intersects the extent', function() {
+      it('returns true', function() {
+        var extent = [1.5, 0.0, 2.5, 1.0];
+        var r = ol.geom.flat.intersectsextent.linearRing(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(true);
+      });
+    });
+    describe('boundary does not intersect the extent and ring does not ' +
+        'contain a corner of the extent', function() {
+          it('returns false', function() {
+            var extent = [2.0, 0.5, 3, 1.5];
+            var r = ol.geom.flat.intersectsextent.linearRing(
+                flatCoordinates, 0, flatCoordinates.length, 2, extent);
+            expect(r).to.be(false);
+          });
+        });
+    describe('ring contains the extent', function() {
+      it('returns true', function() {
+        var extent = [0.75, -0.25, 1.25, 0.25];
+        var r = ol.geom.flat.intersectsextent.linearRing(
+            flatCoordinates, 0, flatCoordinates.length, 2, extent);
+        expect(r).to.be(true);
+      });
+    });
+  });
+});
+
+goog.require('ol.geom.flat.intersectsextent');