voxel/app.js

// @ts-check

import * as T from 'three';
import { VertexNormalsHelper } from 'three/examples/jsm/helpers/VertexNormalsHelper.js';
import { Scene } from './scene.js';
import Region from "./region.js";

let voxels = [];
voxels[Region.I(0, 0, 0)] = true;
voxels[Region.I(1, 0, 0)] = true;
voxels[Region.I(1, 1, 0)] = true;
voxels[Region.I(1, 2, 0)] = true;


let surfaceCubeGeometry = new T.BufferGeometry();
surfaceCubeGeometry.setAttribute("position", new T.BufferAttribute(new Float32Array(), 3));
let surfaceCubeObject = new T.Mesh(
    surfaceCubeGeometry,
    new T.MeshPhongMaterial({color:0x666666, wireframe:false, flatShading:false, side:T.BackSide})
);

let surfaceCubeNormalHelper;

let rebuildSurface = inVoxels =>
{
    let { pos, ind } = Region.Surface(inVoxels);

    let surfaceCubePositions = new T.BufferAttribute(pos, 3);
    surfaceCubePositions.setUsage( T.DynamicDrawUsage );

    surfaceCubeGeometry.dispose();
    surfaceCubeGeometry = new T.BufferGeometry();
    surfaceCubeGeometry.setAttribute("position", surfaceCubePositions);
    surfaceCubeGeometry.setIndex(ind);
    surfaceCubeGeometry.computeVertexNormals();
    surfaceCubeObject.geometry = surfaceCubeGeometry;

};
rebuildSurface(voxels);

surfaceCubeNormalHelper = new VertexNormalsHelper( surfaceCubeObject, -0.2 );



const hitHelper = new T.Mesh
(
    new T.BoxGeometry( 0.2, 0.2, 0.2 ),
    new T.MeshBasicMaterial( {color: 0x00ff00} )
);

Scene({
    DOM:"canvas",
    Init(inScene)
    {   
        let light = new T.PointLight(0xffffff, 1, 100)
        light.position.set(5, 5, -5);
        inScene.add(light);

        inScene.add(surfaceCubeObject);

        //inScene.add(new T.GridHelper(10, 10));
        inScene.add(new T.AxesHelper( 5 ));

        inScene.add( hitHelper );
        inScene.add( surfaceCubeNormalHelper );
    },
    Update(inScene, inScreen, inDelta)
    {
        var i, hits, hit, index;
        if(inScreen.Drag > 0)
        {
            hits = inScreen.Ray.intersectObject(surfaceCubeObject);
            if(hits.length)
            {
                hit = hits[0];
                for(i=1; i<hits.length; i++)
                {
                    if(hits[i].distance < hit.distance)
                    {
                        hit = hits[i];
                        
                    }
                }
                index = Region.I(Math.floor(hit.point.x), Math.floor(hit.point.y), Math.floor(hit.point.z));
                voxels[index] = true;
                rebuildSurface(voxels);
                inScene.remove(surfaceCubeNormalHelper);
                surfaceCubeNormalHelper = new VertexNormalsHelper( surfaceCubeObject, -0.2 );
                inScene.add(surfaceCubeNormalHelper);
                hitHelper.position.set(hit.point.x, hit.point.y, hit.point.z);
                console.log(index, hit);
            }
        }
    }
});


/* old smoothng functions


    let limit = (x, y, z, ax, ay, az) =>
    {
        let centerX = Math.round(x);
        let centerY = Math.round(y);
        let centerZ = Math.round(z);

        let deltaX = ax-centerX;
        let deltaY = ay-centerY;
        let deltaZ = az-centerZ;

        let absDeltaX = Math.abs(deltaX);
        let absDeltaY = Math.abs(deltaY);
        let absDeltaZ = Math.abs(deltaZ);

        let max = absDeltaX;
        if(absDeltaY > max){ max = absDeltaY; }
        if(absDeltaZ > max){ max = absDeltaZ; }

        let lerp = 0.49/max;

        if(lerp <= 1)
        {
            return [
                centerX + deltaX*lerp,
                centerY + deltaY*lerp,
                centerZ + deltaZ*lerp
            ];
        }
        else
        {
            return [ax, ay, az];
        }
    }
    let average = (inArray, inPointInd, inOthersIndArray) =>
    {
        let sum = [0, 0, 0];
        for(let i=0; i<inOthersIndArray.length; i++)
        {
            let otherInd = inOthersIndArray[i]*3;
            sum[0] += inArray[otherInd+0];
            sum[1] += inArray[otherInd+1];
            sum[2] += inArray[otherInd+2];
        }
        
        let pointX = inPointInd*3 + 0;
        let pointY = inPointInd*3 + 1;
        let pointZ = inPointInd*3 + 2;
        let reducer = inOthersIndArray.length;

        let limited = limit(inArray[pointX], inArray[pointY], inArray[pointZ], sum[0]/reducer, sum[1]/reducer, sum[2]/reducer);

        inArray[pointX] = limited[0];
        inArray[pointY] = limited[1];
        inArray[pointZ] = limited[2];
    };
    let smooth = (inVertsArray, inNeighborsArray, inTimes) =>
    {
        let count = inVertsArray.length/3;
        for(let t=0; t<inTimes; t++)
        {
            for(let i=0; i<count; i++)
            {
                average(inVertsArray, i, inNeighborsArray[i]);
            }
        }
        return inVertsArray;
    }


*/