fullib-js/src/js/3D/getGeometry.js

Full Javascript Animation Library

import * as THREE from "three";
let SimplexNoise = require('simplex-noise');
let noise2D = SimplexNoise.createNoise2D();

function clamp(a){
    return Math.max(0,Math.min(1,a));
}
export default function getGeometry(detail,offsettop){
    offsettop = offsettop || 0;
    let geometry = new THREE.BufferGeometry();
    let number = detail;
    let width = 2;
    let height = 2;

    let gran = width/number;
    let granH = gran*Math.sqrt(3)/2;
    let rows = height/granH;

    let offsets = []
    let positions = [];
    let centroids = [];
    let control0 = [];
    let control1 = [];
    let randoms = [];
    let uvs = [];
    let currentShift = 0;
    let bary = [];
    let currentheight = 0;
    let numberOfTriangles = 0;
    let scale = 2;

    for (let j = 0; j < rows; j++) {
        currentheight = j*granH;
        if(j%2===1){ currentShift = -gran/2;}
        else{currentShift = 0;}
        for (let i = 0; i <= number; i++) {
            let sign = Math.sign(i*gran + currentShift - width/2)
            // sign =1
            // first triangle
            positions.push(i*gran + currentShift - width/2,currentheight - height/2,0);
            uvs.push((i*gran + currentShift)/width, (currentheight)/height)
            positions.push(i*gran + gran/2 + currentShift - width/2,granH + currentheight - height/2,0);
            uvs.push((i*gran + gran/2 + currentShift)/width, (granH + currentheight)/height)
            positions.push(i*gran - gran/2 + currentShift - width/2,granH + currentheight - height/2,0);
            uvs.push((i*gran - gran/2 + currentShift)/width, (granH + currentheight)/height)

            let simp = noise2D(i/rows, j/rows) + Math.random()
            let o = clamp(currentheight/height + 2*simp/detail);
            let r = Math.random()
            offsets.push(o,clamp(o + 0.1*offsettop),clamp(o + 0.1*offsettop));
            randoms.push(r,r,r);
            let c = [i*gran + currentShift - width/2,currentheight - height/2,0];
            centroids.push(...c,...c,...c)

            let ctrl0 = [
                scale*sign*THREE.MathUtils.randFloat(-.3, 0.3),
                -scale*THREE.MathUtils.randFloat(-.3, 0.3) * 1.5,
                -THREE.MathUtils.randFloatSpread(.5)
            ];
            let ctrl1 = [
                scale*sign*THREE.MathUtils.randFloat(0.3, 0.6),
                -scale*THREE.MathUtils.randFloat(0.3, 0.6) * 1.5,
                -THREE.MathUtils.randFloatSpread(.5)
            ];
            control0.push(...ctrl0,...ctrl0,...ctrl0)
            control1.push(...ctrl1,...ctrl1,...ctrl1)


            bary.push(0,0,1, 0,1,0, 1,0,0);
            // second triangle
            positions.push(i*gran + currentShift - width/2,currentheight - height/2,0);
            uvs.push((i*gran + currentShift)/width, (currentheight)/height)
            positions.push(i*gran + gran + currentShift - width/2,currentheight - height/2,0);
            uvs.push((i*gran + gran + currentShift)/width, (currentheight)/height)
            positions.push(i*gran + gran/2 + currentShift - width/2,granH + currentheight - height/2,0);
            uvs.push((i*gran + gran/2 + currentShift)/width, (granH + currentheight)/height)

            simp = noise2D((i+1)/rows, j/rows) + Math.random()
            let o1 = clamp(currentheight/height + 2*simp/detail);
            r = Math.random()
            offsets.push(o1,o1,clamp(o1 + 0.1*offsettop));
            randoms.push(r,r,r);
            let c1 = [i*gran + currentShift - width/2,currentheight - height/2,0]

            control0.push(...ctrl0,...ctrl0,...ctrl0)
            control1.push(...ctrl1,...ctrl1,...ctrl1)

            centroids.push(...c1,...c1,...c1)
            bary.push(0,0,1, 0,1,0, 1,0,0);

            numberOfTriangles += 2;
        }
    }

    geometry.setAttribute( 'position', new THREE.BufferAttribute( new Float32Array(positions), 3 ) );
    geometry.setAttribute( 'bary', new THREE.BufferAttribute( new Float32Array(bary), 3 ) );
    geometry.setAttribute( 'uv', new THREE.BufferAttribute( new Float32Array(uvs), 2 ) );
    geometry.setAttribute( 'offset', new THREE.BufferAttribute( new Float32Array(offsets), 1 ) );
    geometry.setAttribute( 'centroid1', new THREE.BufferAttribute( new Float32Array(centroids), 3 ) );
    geometry.setAttribute( 'control0', new THREE.BufferAttribute( new Float32Array(control0), 3 ) );
    geometry.setAttribute( 'control1', new THREE.BufferAttribute( new Float32Array(control1), 3 ) );
    geometry.setAttribute( 'random', new THREE.BufferAttribute( new Float32Array(randoms), 1 ) );

    return geometry;
}