diff options
author | sanine <sanine.not@pm.me> | 2022-05-31 20:52:15 -0500 |
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committer | sanine <sanine.not@pm.me> | 2022-05-31 20:52:15 -0500 |
commit | 5efc7885e1c3959aa165be640858ffb3f8a5860b (patch) | |
tree | 6865327d6affd6df2c4f61ed3b9d5ab446e2b23e /src/Terrain.js | |
parent | 8aa6645f2311de78f74b35f804cc45c7fcf38f57 (diff) |
refactor: remove modules/ folder
Diffstat (limited to 'src/Terrain.js')
-rw-r--r-- | src/Terrain.js | 206 |
1 files changed, 0 insertions, 206 deletions
diff --git a/src/Terrain.js b/src/Terrain.js deleted file mode 100644 index 291a4fc..0000000 --- a/src/Terrain.js +++ /dev/null @@ -1,206 +0,0 @@ -'use strict'; - -import Voronoi from './3rdparty/rhill-voronoi-core.js'; - -import { lerp, clamp, useAverage } from './modules/Util.js'; -import { dist, AABB, QuadTree } from './modules/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.voronoi = v.compute(seed_points, {xl: 0, xr: 1, yt: 0, yb: 1}); - - this.tree = new QuadTree(1,1); - let index = 0; - for (let v of this.voronoi.vertices) { - v.height = v.y; - v.index = index; - index += 1; - this.tree.insert(v); - } - - this.graph = {}; - for (let e of this.voronoi.edges) { - if (!this.graph[e.va.index]) this.graph[e.va.index] = new Set(); - if (!this.graph[e.vb.index]) this.graph[e.vb.index] = new Set(); - - this.graph[e.va.index].add(e.vb.index); - this.graph[e.vb.index].add(e.va.index); - } - } - - - 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)); - } - - - getNeighbors(point) { - const indices = Array.from(this.graph[point.index]); - return indices.map( index => this.voronoi.vertices[index] ); - } - - - renderGrid(ct) { - ct.save(); - ct.lineWidth = 0.001; - for (let edge of this.voronoi.edges) { - ct.fillStyle = `hsl(${edge.va.height}, 100%, 50%)`; - ct.beginPath(); - ct.arc(edge.va.x, edge.va.y, 0.0005, 0, 2*Math.PI); - ct.closePath(); - ct.fill(); - - /*ct.beginPath(); - ct.moveTo(edge.va.x, edge.va.y); - ct.lineTo(edge.vb.x, edge.vb.y); - ct.closePath(); - ct.stroke(); - */ - } - ct.restore(); - } - - render(ct) { - function rgb(r, g, b) { - this.r = r; this.g = g; this.b = b; - } - const renderRgb = rgb => `rgb(${rgb.r}, ${rgb.g}, ${rgb.b})`; - const lerpColors = (a, b, alpha) => new rgb( - lerp(a.r, b.r, alpha), - lerp(a.g, b.g, alpha), - lerp(a.b, b.b, alpha) - ); - const getBucket = (value, min, max, numBuckets) => { - const delta = max - min; - const step = delta/numBuckets; - return clamp(Math.floor((value-min)/step), 0, numBuckets-1); - } - const getColor = (value, min, max, colors) => { - if (value < min) return colors[0]; - if (value >= max) return colors[colors.length-1]; - - const step = (max - min)/(colors.length - 1); - - const index = getBucket(value, min, max, colors.length-1); - const alpha = (value - (index*step) - min)/step; - const color = lerpColors( - colors[index], colors[index+1], - alpha - ); - if (color.r <= 0) - console.log(value, index, alpha, color); - return color; - } - - const colors = [ - /* ocean */ - new rgb(31, 59, 68), - new rgb(68, 130, 149), - - /* land */ - new rgb(229, 199, 169), - new rgb(198, 133, 67), - new rgb(117, 89, 61), - - /* mountain */ - new rgb(82, 74, 64), - new rgb(82, 74, 64), - new rgb(255, 255, 255), - ]; - ct.save(); - - for (let cell of this.voronoi.cells) { - ct.beginPath(); - - let height = 0; - let count = 1; - for (let edge of cell.halfedges) { - const p0 = edge.getStartpoint(); - const p1 = edge.getEndpoint(); - height += p0.height; - count += 1; - ct.lineTo(p0.x, p0.y); - ct.lineTo(p1.x, p1.y); - } - ct.closePath(); - height /= count; - height = 10 * Math.floor(height/10); - const color = getColor(height, 0, 100, colors); - if (color.r <=0) console.log(color); - ct.fillStyle = renderRgb(color); - ct.strokeStyle = renderRgb(color); - ct.stroke(); - ct.fill(); - } - - ct.restore(); - } -} - -export { lloydRelax }; -export default Terrain; |