# limitations under the License.
# Provides interfaces and classes to represent basic geometry needs.
-module points_and_lines
+module points_and_lines is serialize
+
+import serialization
# An abstract 2d point, strongly linked to its implementation `Point`
interface IPoint[N: Numeric]
- # horizontal coordinate
+
+ # Horizontal coordinate
fun x: N is abstract
- # vertical coordinate
+
+ # Vertical coordinate
fun y: N is abstract
redef fun to_s do return "({x}, {y})"
+
+ # Distance with `other`
+ #
+ # ~~~
+ # var p0 = new Point[Float](0.0, 0.0)
+ # var p1 = new Point[Float](2.0, 3.0)
+ # assert p0.dist(p1).is_approx(3.6, 0.01)
+ # ~~~
+ #
+ # TODO 3D implementation.
+ fun dist(other: Point[Numeric]): N
+ do
+ return x.value_of(dist2(other).to_f.sqrt)
+ end
+
+ # Square of the distance with `other`
+ #
+ # May be used as an approximation to compare distance between two points.
+ #
+ # ~~~
+ # var p0 = new Point[Float](0.0, 0.0)
+ # var p1 = new Point[Float](2.0, 3.0)
+ # assert p0.dist2(p1) == 13.0
+ # ~~~
+ #
+ # TODO 3D implementation.
+ fun dist2(other: Point[Numeric]): N
+ do
+ var dx = other.x.sub(x)
+ var dy = other.y.sub(y)
+ var s = (dx.mul(dx)).add(dy.mul(dy))
+ return x.value_of(s)
+ end
+
+ # Linear interpolation between `self` and `other` at `p` out of `1.0`
+ #
+ # ~~~
+ # var p0 = new Point[Float](0.0, 0.0)
+ # var p1 = new Point[Float](2.0, 3.0)
+ # assert p0.lerp(p1, 0.0) == p0
+ # assert p0.lerp(p1, 1.0) == p1
+ # assert p0.lerp(p1, 0.5) == new Point[Float](1.0, 1.5)
+ # ~~~
+ #
+ # TODO 3D implementation.
+ fun lerp(other: Point[Numeric], p: Float): Point[N]
+ do
+ var xx = x.to_f + (other.x.to_f - x.to_f).to_f * p
+ var yy = y.to_f + (other.y.to_f - y.to_f).to_f * p
+ return new Point[N](x.value_of(xx), y.value_of(yy))
+ end
+
+ redef fun ==(o) do return o isa IPoint[Numeric] and o.x == x and o.y == y
end
# A 2d point and an implementation of `IPoint`
class Point[N: Numeric]
super IPoint[N]
- redef var x: N
- redef var y: N
+ redef var x: N is writable
+ redef var y: N is writable
end
# An abstract 3d point, strongly linked to its implementation `Point3d`
super IPoint3d[N]
super Point[N]
- redef var z: N
+ redef var z: N is writable
end
# An abstract 2d line segment
interface ILine[N: Numeric]
+ # The type of points that ends the segment
type P: IPoint[N]
+ # The point that is the left-end of the segment
fun point_left: P is abstract
+
+ # The point that is the right-end of the segment
fun point_right: P is abstract
redef fun to_s do return "{point_left}--{point_right}"
class Line[N: Numeric]
super ILine[N]
- redef var point_left: P
- redef var point_right: P
+ redef var point_left
+ redef var point_right
init
do
point_right = a
end
end
-
end
# An abstract 3d line segment