Slab decomposition data structure for 2D vertical ray queries
npm install slab-decompositionslab-decomposition
==================
Given a collection of line segments, constructs a slab decomposition for the purpose of point location queries. This implementation uses a functional red-black tree to store the slabs, requires O(n log(n)) space and answers vertical ray queries in O(log(n)) time.
``javascript
var makeSlab = require("slab-decomposition")
var slabs = makeSlab([
[[0, 0], [10, 10]],
[[10,10], [20, 0]],
[[5, 5], [20, 0]]
])
for(var i=-10; i<10; ++i) {
console.log(slabs.castUp([i, -1]))
}
`
`
npm install slab-decomposition
* segments is a collection of line segments which only overlap at their end points
Returns A slab decomposition data structure
going upward along [0,1]. Returns the index of the first segment hit.*
point` is the base point of the rayReturns The index of the first segment hit by point, otherwise -1 if no segment intersects the ray.