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Diffstat (limited to 'src/modules/Terrain.js')
-rw-r--r-- | src/modules/Terrain.js | 111 |
1 files changed, 0 insertions, 111 deletions
diff --git a/src/modules/Terrain.js b/src/modules/Terrain.js deleted file mode 100644 index 21908ac..0000000 --- a/src/modules/Terrain.js +++ /dev/null @@ -1,111 +0,0 @@ -'use strict'; - -import Voronoi from './3rdparty/rhill-voronoi-core.js'; - -import { useAverage } from './Util.js'; -import { AABB, QuadTree } from './Geometry.js'; - - -/* from here on up, we always assume that points live in the range [(0,0), (1,1)) */ - -function lloydRelax(point_set, density) { - /* setup quadtree and averages */ - let tree = new QuadTree(1,1); - let averages = {}; - for (let i=0; i<point_set.length; i++) { - const point = point_set[i]; - point.index = i; - tree.insert(point); - - let [avg, append] = useAverage(); - const cent_x = { avg, append }; - [avg, append] = useAverage(); - const cent_y = { avg, append }; - averages[i] = { cent_x, cent_y }; - } - - /* compute average centroids */ - for (let x=0; x<1; x += 1/density) { - for (let y=0; y<1; y += 1/density) { - const point = { x, y }; - const closest = tree.closest(point); - const { cent_x, cent_y } = averages[closest.index]; - cent_x.append(point.x); - cent_y.append(point.y); - } - } - - /* return centroid points */ - const result = []; - for (let i=0; i<point_set.length; i++) { - const point = { x: averages[i].cent_x.avg(), y: averages[i].cent_y.avg() }; - result.push(point); - } - return result; -} - - -class Terrain { - constructor() { - const N_SEED_POINTS = 2**12; - const N_RELAX_ITERATIONS = 1; - const RELAX_DENSITY = 400; - const randomPoint = () => ({x: Math.random(), y: Math.random()}); - - this.min_height = 0; - this.max_height = 0; - - let seed_points = []; - for (let i=0; i<N_SEED_POINTS; i++) seed_points.push(randomPoint()); - - for (let i=0; i<N_RELAX_ITERATIONS; i++) - lloydRelax(seed_points, RELAX_DENSITY); - - const v = new Voronoi(); - this.graph = v.compute(seed_points, {xl: 0, xr: 1, yt: 0, yb: 1}); - - this.tree = new QuadTree(1,1); - for (let v of this.graph.vertices) { - v.height = 0; - this.tree.insert(v); - } - } - - - applyBrush(x, y, f, strength, radius) { - const region = new AABB(x-radius, y-radius, 2*radius, 2*radius); - const points = this.tree.root.getPointsInRegion(region); - - const dist2 = (a, b) => (a.x - b.x)**2 + (a.y - b.y)**2; - - const sigma = radius/3; - const beta = 1/(2*sigma*sigma); - const center = { x, y }; - const power = pt => Math.exp(-beta * dist2(pt, center)); - - for (let pt of points) f(pt, strength * power(pt)); - } - - - renderGrid(ct) { - ct.save(); - ct.lineWidth = 0.001; - for (let edge of this.graph.edges) { - ct.fillStyle = `hsl(${edge.va.height}, 100%, 50%)`; - ct.beginPath(); - ct.arc(edge.va.x, edge.va.y, 0.005, 0, 2*Math.PI); - ct.closePath(); - ct.fill(); - - ct.beginPath(); - ct.moveTo(edge.va.x, edge.va.y); - ct.lineTo(edge.vb.x, edge.vb.y); - ct.closePath(); - ct.stroke(); - } - ct.restore(); - } -} - -export { lloydRelax }; -export default Terrain; |