Merge pull request #118 from mbattifarano/line-type

Add `Line` type

src/algorithm/area.rs

@@ -1,5 +1,5 @@
 use num_traits::Float;
-use types::{LineString, Polygon, MultiPolygon, Bbox};
+use types::{Line, LineString, Polygon, MultiPolygon, Bbox};
 
 /// Calculation of the area.
 
@@ -31,6 +31,13 @@ fn get_linestring_area<T>(linestring: &LineString<T>) -> T where T: Float {
     tmp / (T::one() + T::one())
 }
 
+impl<T> Area<T> for Line<T>
+    where T: Float
+{
+    fn area(&self) -> T {
+        T::zero()
+    }
+}
 
 impl<T> Area<T> for Polygon<T>
     where T: Float
@@ -59,7 +66,7 @@ impl<T> Area<T> for Bbox<T>
 
 #[cfg(test)]
 mod test {
-    use types::{Coordinate, Point, LineString, Polygon, MultiPolygon, Bbox};
+    use types::{Coordinate, Point, Line, LineString, Polygon, MultiPolygon, Bbox};
     use algorithm::area::Area;
 
     // Area of the polygon
@@ -111,4 +118,10 @@ mod test {
         assert_eq!(mpoly.area(), 102.);
         assert_relative_eq!(mpoly.area(), 102.);
     }
+    #[test]
+    fn area_line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line1 = Line::new(p(0.0, 0.0), p(1.0, 1.0));
+        assert_eq!(line1.area(), 0.);
+    }
 }

src/algorithm/boundingbox.rs

@@ -1,6 +1,6 @@
 use num_traits::Float;
 
-use types::{Bbox, Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
+use types::{Bbox, Point, MultiPoint, Line, LineString, MultiLineString, Polygon, MultiPolygon};
 
 /// Calculation of the bounding box of a geometry.
 
@@ -65,6 +65,19 @@ impl<T> BoundingBox<T> for MultiPoint<T>
     }
 }
 
+impl<T> BoundingBox<T> for Line<T>
+    where T: Float
+{
+    fn bbox(&self) -> Option<Bbox<T>> {
+        let a = self.start;
+        let b = self.end;
+        let (xmin, xmax) = if a.x() <= b.x() {(a.x(), b.x())} else {(b.x(), a.x())};
+        let (ymin, ymax) = if a.y() <= b.y() {(a.y(), b.y())} else {(b.y(), a.y())};
+        Some(Bbox {xmin: xmin, xmax: xmax,
+                   ymin: ymin, ymax: ymax})
+    }
+}
+
 impl<T> BoundingBox<T> for LineString<T>
     where T: Float
 {
@@ -114,7 +127,7 @@ impl<T> BoundingBox<T> for MultiPolygon<T>
 
 #[cfg(test)]
 mod test {
-    use types::{Bbox, Coordinate, Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
+    use types::{Bbox, Coordinate, Point, MultiPoint, Line, LineString, MultiLineString, Polygon, MultiPolygon};
     use algorithm::boundingbox::BoundingBox;
 
     #[test]
@@ -175,4 +188,14 @@ mod test {
         let bbox = Bbox{xmin: -60., ymax: 80., xmax: 50., ymin: -70.};
         assert_eq!(bbox, mpoly.bbox().unwrap());
     }
+    #[test]
+    fn line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line1 = Line::new(p(0., 1.), p(2., 3.));
+        let line2 = Line::new(p(2., 3.), p(0., 1.));
+        assert_eq!(line1.bbox().unwrap(),
+                   Bbox {xmin: 0., xmax: 2., ymin: 1., ymax: 3.});
+        assert_eq!(line2.bbox().unwrap(),
+                   Bbox {xmin: 0., xmax: 2., ymin: 1., ymax: 3.});
+    }
 }

src/algorithm/centroid.rs

@@ -1,6 +1,6 @@
 use num_traits::{Float, FromPrimitive};
 
-use types::{Point, LineString, Polygon, MultiPolygon, Bbox};
+use types::{Point, Line, LineString, Polygon, MultiPolygon, Bbox};
 use algorithm::area::Area;
 use algorithm::distance::Distance;
 
@@ -54,6 +54,17 @@ fn simple_polygon_centroid<T>(poly_ext: &LineString<T>) -> Option<Point<T>>
     Some(Point::new(sum_x / (six * area), sum_y / (six * area)))
 }
 
+impl<T> Centroid<T> for Line<T>
+    where T: Float
+{
+    fn centroid(&self) -> Option<Point<T>> {
+        let two = T::one() + T::one();
+        let x = (self.start.x() + self.end.x()) / two;
+        let y = (self.start.y() + self.end.y()) / two;
+        Some(Point::new(x, y))
+    }
+}
+
 impl<T> Centroid<T> for LineString<T>
     where T: Float
 {
@@ -170,7 +181,7 @@ impl<T> Centroid<T> for Point<T>
 
 #[cfg(test)]
 mod test {
-    use types::{COORD_PRECISION, Coordinate, Point, LineString, Polygon, MultiPolygon, Bbox};
+    use types::{COORD_PRECISION, Coordinate, Point, Line, LineString, Polygon, MultiPolygon, Bbox};
     use algorithm::centroid::Centroid;
     use algorithm::distance::Distance;
     // Tests: Centroid of LineString
@@ -293,4 +304,10 @@ mod test {
         let point = Point(Coordinate { x: 2., y: 75. });
         assert_eq!(point, bbox.centroid().unwrap());
     }
+    #[test]
+    fn line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line1 = Line::new(p(0., 1.), p(1., 3.));
+        assert_eq!(line1.centroid(), Some(p(0.5, 2.)));
+    }
 }

src/algorithm/contains.rs

@@ -1,6 +1,6 @@
 use num_traits::{Float, ToPrimitive};
 
-use types::{COORD_PRECISION, Point, LineString, Polygon, MultiPolygon, Bbox};
+use types::{COORD_PRECISION, Point, Line, LineString, Polygon, MultiPolygon, Bbox};
 use algorithm::intersects::Intersects;
 use algorithm::distance::Distance;
 
@@ -70,6 +70,65 @@ impl<T> Contains<Point<T>> for LineString<T>
         false
     }
 }
+
+impl<T> Contains<Point<T>> for Line<T>
+    where T: Float
+{
+    fn contains(&self, p: &Point<T>) -> bool {
+        self.intersects(p)
+    }
+}
+
+impl<T> Contains<Line<T>> for Line<T>
+    where T: Float
+{
+    fn contains(&self, line: &Line<T>) -> bool {
+        self.contains(&line.start) & self.contains(&line.end)
+    }
+}
+
+impl<T> Contains<LineString<T>> for Line<T> 
+    where T: Float
+{
+    fn contains(&self, linestring: &LineString<T>) -> bool {
+        linestring.0.iter().all(|pt| self.contains(pt))
+    }
+}
+
+impl<T> Contains<Line<T>> for LineString<T>
+    where T: Float
+{
+    fn contains(&self, line: &Line<T>) -> bool {
+        let (p0, p1) = (line.start, line.end);
+        let mut look_for: Option<Point<T>> = None;
+        for l in self.0.windows(2) {
+            let segment = Line::new(l[0], l[1]);
+            if look_for.is_none() {
+                // If segment contains an endpoint of line, we mark the other endpoint as the
+                // one we are looking for.
+                if segment.contains(&p0) {
+                    look_for = Some(p1);
+                } else if segment.contains(&p1) {
+                    look_for = Some(p0);
+                }
+            }
+            if let Some(p) = look_for {
+                // If we are looking for an endpoint, we need to either find it, or show that we
+                // should continue to look for it
+                if segment.contains(&p) {
+                    // If the segment contains the endpoint we are looking for we are done
+                    return true;
+                } else if !line.contains(&segment.end) {
+                    // If not, and the end of the segment is not on the line, we should stop
+                    // looking 
+                    look_for = None
+                }
+            }
+        }
+        return false;
+    }
+}
+
 #[derive(PartialEq, Clone, Debug)]
 enum PositionPoint {
     OnBoundary,
@@ -139,6 +198,19 @@ impl<T> Contains<Point<T>> for MultiPolygon<T>
     }
 }
 
+impl<T> Contains<Line<T>> for Polygon<T>
+    where T: Float
+{
+    fn contains(&self, line: &Line<T>) -> bool {
+        // both endpoints are contained in the polygon and the line
+        // does NOT intersect the exterior or any of the interior boundaries
+        self.contains(&line.start) &&
+            self.contains(&line.end) &&
+            !self.exterior.intersects(line) &&
+            !self.interiors.iter().any(|inner| inner.intersects(line))
+    }
+}
+
 impl<T> Contains<LineString<T>> for Polygon<T>
     where T: Float
 {
@@ -152,7 +224,6 @@ impl<T> Contains<LineString<T>> for Polygon<T>
     }
 }
 
-
 impl<T> Contains<Point<T>> for Bbox<T>
     where T: Float
 {
@@ -173,7 +244,7 @@ impl<T> Contains<Bbox<T>> for Bbox<T>
 
 #[cfg(test)]
 mod test {
-    use types::{Coordinate, Point, LineString, Polygon, MultiPolygon, Bbox};
+    use types::{Coordinate, Point, Line, LineString, Polygon, MultiPolygon, Bbox};
     use algorithm::contains::Contains;
     /// Tests: Point in LineString
     #[test]
@@ -321,4 +392,78 @@ mod test {
         assert_eq!(true, bbox_xl.contains(&bbox_sm));
         assert_eq!(false, bbox_sm.contains(&bbox_xl));
     }
+    #[test]
+    fn point_in_line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let p0 = p(2., 4.);
+        // vertical line
+        let line1 = Line::new(p(2., 0.), p(2., 5.));
+        // point on line, but outside line segment
+        let line2 = Line::new(p(0., 6.), p(1.5, 4.5));
+        // point on line
+        let line3 = Line::new(p(0., 6.), p(3., 3.));
+        assert!(line1.contains(&p0));
+        assert!(!line2.contains(&p0));
+        assert!(line3.contains(&p0));
+    }
+    #[test]
+    fn line_in_line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line0 = Line::new(p(0., 1.), p(3., 4.));
+        // first point on line0, second not
+        let line1 = Line::new(p(1., 2.), p(2., 2.));
+        // co-linear, but extends past the end of line0
+        let line2 = Line::new(p(1., 2.), p(4., 5.));
+        // contained in line0
+        let line3 = Line::new(p(1., 2.), p(3., 4.));
+        assert!(!line0.contains(&line1));
+        assert!(!line0.contains(&line2));
+        assert!(line0.contains(&line3));
+    }
+    #[test]
+    fn linestring_in_line_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line = Line::new(p(0., 1.), p(3., 4.));
+        // linestring0 in line
+        let linestring0 = LineString(vec![p(0.1, 1.1), p(1., 2.), p(1.5, 2.5)]);
+        // linestring1 starts and ends in line, but wanders in the middle
+        let linestring1 = LineString(vec![p(0.1, 1.1), p(2., 2.), p(1.5, 2.5)]);
+        // linestring2 is co-linear, but extends beyond line
+        let linestring2 = LineString(vec![p(0.1, 1.1), p(1., 2.), p(4., 5.)]);
+        // no part of linestring3 is contained in line
+        let linestring3 = LineString(vec![p(1.1, 1.1), p(2., 2.), p(2.5, 2.5)]);
+        assert!(line.contains(&linestring0));
+        assert!(!line.contains(&linestring1));
+        assert!(!line.contains(&linestring2));
+        assert!(!line.contains(&linestring3));
+    }
+    #[test]
+    fn line_in_polygon_test() {
+        let p = |x, y| Point(Coordinate { x: x, y: y });
+        let line = Line::new(p(0., 1.), p(3., 4.));
+        let linestring0 = LineString(vec![p(-1., 0.), p(5., 0.), p(5., 5.), p(0., 5.), p(-1., 0.)]);
+        let poly0 = Polygon::new(linestring0, Vec::new());
+        let linestring1 = LineString(vec![p(0., 0.), p(0., 2.), p(2., 2.), p(2., 0.), p(0., 0.)]);
+        let poly1 = Polygon::new(linestring1, Vec::new());
+        assert!(poly0.contains(&line));
+        assert!(!poly1.contains(&line));
+    }
+    #[test]
+    fn line_in_linestring_test() {
+        let line0 = Line::new(Point::new(1., 1.), Point::new(2., 2.));
+        // line0 is completely contained in the second segment
+        let linestring0 = LineString(vec![Point::new(0., 0.5), Point::new(0.5, 0.5),
+                                          Point::new(3., 3.)]);
+        // line0 is contained in the last three segments
+        let linestring1 = LineString(vec![Point::new(0., 0.5), Point::new(0.5, 0.5),
+                                          Point::new(1.2, 1.2), Point::new(1.5, 1.5),
+                                          Point::new(3., 3.)]);
+        // line0 endpoints are contained in the linestring, but the fourth point is off the line
+        let linestring2 = LineString(vec![Point::new(0., 0.5), Point::new(0.5, 0.5),
+                                          Point::new(1.2, 1.2), Point::new(1.5, 0.),
+                                          Point::new(2., 2.), Point::new(3., 3.)]);
+        assert!(linestring0.contains(&line0));
+        assert!(linestring1.contains(&line0));
+        assert!(!linestring2.contains(&line0));
+    }
 }

src/algorithm/distance.rs

@@ -1,7 +1,7 @@
 use std::cmp::Ordering;
 use std::collections::BinaryHeap;
 use num_traits::{Float, ToPrimitive};
-use types::{Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
+use types::{Point, Line, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
 use algorithm::contains::Contains;
 use num_traits::pow::pow;
 
@@ -263,9 +263,26 @@ impl<T> Distance<T, Point<T>> for LineString<T>
     }
 }
 
+impl<T> Distance<T, Point<T>> for Line<T>
+    where T: Float
+{
+    /// Minimum distance from a Line to a Point
+    fn distance(&self, point: &Point<T>) -> T {
+        line_segment_distance(point, &self.start, &self.end)
+    }
+}
+impl<T> Distance<T, Line<T>> for Point<T>
+    where T: Float
+{
+    /// Minimum distance from a Line to a Point
+    fn distance(&self, line: &Line<T>) -> T {
+        line.distance(self)
+    }
+}
+
 #[cfg(test)]
 mod test {
-    use types::{Point, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
+    use types::{Point, Line, MultiPoint, LineString, MultiLineString, Polygon, MultiPolygon};
     use algorithm::distance::{Distance, line_segment_distance};
 
     #[test]
@@ -457,4 +474,19 @@ mod test {
         let p = Point::new(50.0, 50.0);
         assert_eq!(p.distance(&mp), 64.03124237432849)
     }
+    #[test]
+    fn distance_line_test() {
+        let line0 = Line::new(Point::new(0., 0.), Point::new(5., 0.));
+        let p0 = Point::new(2., 3.);
+        let p1 = Point::new(3., 0.);
+        let p2 = Point::new(6., 0.);
+        assert_eq!(line0.distance(&p0), 3.);
+        assert_eq!(p0.distance(&line0), 3.);
+
+        assert_eq!(line0.distance(&p1), 0.);
+        assert_eq!(p1.distance(&line0), 0.);
+
+        assert_eq!(line0.distance(&p2), 1.);
+        assert_eq!(p2.distance(&line0), 1.);
+    }
 }