tidwall 6257ddba78 Faster point in polygon / GeoJSON updates
The big change is that the GeoJSON package has been completely
rewritten to fix a few of geometry calculation bugs, increase
performance, and to better follow the GeoJSON spec RFC 7946.

GeoJSON updates

- A LineString now requires at least two points.
- All json members, even foreign, now persist with the object.
- The bbox member persists too but is no longer used for geometry
  calculations. This is change in behavior. Previously Tile38 would
  treat the bbox as the object's physical rectangle.
- Corrections to geometry intersects and within calculations.

Faster spatial queries

- The performance of Point-in-polygon and object intersect operations
  are greatly improved for complex polygons and line strings. It went
  from O(n) to roughly O(log n).
- The same for all collection types with many children, including
  FeatureCollection, GeometryCollection, MultiPoint, MultiLineString,
  and MultiPolygon.

Codebase changes

- The pkg directory has been renamed to internal
- The GeoJSON internal package has been moved to a seperate repo at
  https://github.com/tidwall/geojson. It's now vendored.

Please look out for higher memory usage for datasets using complex
shapes. A complex shape is one that has 64 or more points. For these
shapes it's expected that there will be increase of least 54 bytes per
point.
2018-10-13 04:30:48 -07:00

78 lines
1.5 KiB
Go

// Copyright 2018 Joshua J Baker. All rights reserved.
// Use of this source code is governed by an MIT-style
// license that can be found in the LICENSE file.
package geometry
// Point ...
type Point struct {
X, Y float64
}
// Move ...
func (point Point) Move(deltaX, deltaY float64) Point {
return Point{X: point.X + deltaX, Y: point.Y + deltaY}
}
// Empty ...
func (point Point) Empty() bool {
return false
}
// Rect ...
func (point Point) Rect() Rect {
return Rect{point, point}
}
// ContainsPoint ...
func (point Point) ContainsPoint(other Point) bool {
return point == other
}
// IntersectsPoint ...
func (point Point) IntersectsPoint(other Point) bool {
return point == other
}
// ContainsRect ...
func (point Point) ContainsRect(rect Rect) bool {
return point.Rect() == rect
}
// IntersectsRect ...
func (point Point) IntersectsRect(rect Rect) bool {
return rect.ContainsPoint(point)
}
// ContainsLine ...
func (point Point) ContainsLine(line *Line) bool {
if line == nil {
return false
}
return !line.Empty() && line.Rect() == point.Rect()
}
// IntersectsLine ...
func (point Point) IntersectsLine(line *Line) bool {
if line == nil {
return false
}
return line.IntersectsPoint(point)
}
// ContainsPoly ...
func (point Point) ContainsPoly(poly *Poly) bool {
if poly == nil {
return false
}
return !poly.Empty() && poly.Rect() == point.Rect()
}
// IntersectsPoly ...
func (point Point) IntersectsPoly(poly *Poly) bool {
if poly == nil {
return false
}
return poly.IntersectsPoint(point)
}