voxel/region.js

export const Kernel = 
{
    Corners:
    [
        [ 1,  1, -1],
        [ 1, -1, -1],
        [-1,  1, -1],
        [-1, -1, -1],
        [ 1,  1,  1],
        [ 1, -1,  1],
        [-1,  1,  1],
        [-1, -1,  1]
    ],
    Cardinal:
    [
        [ 1,  0,  0],
        [ 0,  1,  0],
        [-1,  0,  0],
        [ 0, -1,  0],
        [ 0,  0,  1],
        [ 0,  0, -1]
    ],
    Loop(inList, inVector, inHandler)
    {
        for(let i=0; i<inList.length; i++)
        {
            let delta = inList[i];
            if(inHandler(inVector[0]+delta[0], inVector[1]+delta[1], inVector[2]+delta[2]))
            {
                return;
            }
        }
    }
};
export const Region = 
{
    Create()
    {
        return {
            Voxels:[],
            Filled:[],
            Surface:[]
        };
    },
    I(inX, inY, inZ)
    {
        return inX + inY*16 + inZ*256;
    },
    XYZ(inI)
    {
        let zWhole = Math.floor(inI / 256);
        let zPart = inI % 256;
        let yWhole = Math.floor(zPart / 16);
        let yPart = zPart % 16;
        return [yPart, yWhole, zWhole];
    },
    Update(inVoxels)
    {
        function Face(a, b, c, d)
        {
            Edge(a, b);
            Edge(b, c);
            Edge(c, d);
            Edge(d, a);
        }
        function Edge(a, b)
        {

        }

        var i;
        var BA, BU, BC, BR,  TA, TU, TC, TR,  CL, CD, CB;
        for(i=0; i<inVoxels.length; i++)
        {
            if(inVoxels[i])
            {
                let [x, y, z] = Region.IndexToCoords(i);

                // bottom: at, "up", corner, right
                BA = i;
                BU = Region.I(x+1, y,   z);
                BC = Region.I(x+1, y+1, z);
                BR = Region.I(x,   y+1, z);

                // top: at, "up" corner, right
                TA = Region.I(x,   y,   z+1);
                TU = Region.I(x+1, y,   z+1);
                TC = Region.I(x+1, y+1, z+1);
                TR = Region.I(x,   y+1, z+1);

                // check: left, "down", below
                CL = Region.I(x-1, y,   z);
                CD = Region.I(x,   y-1, z);
                CB = Region.I(x,   y,   z-1);

                if(!inVoxels[BU]){ Face(BU, BC, TC, TU); }
                if(!inVoxels[BR]){ Face(BC, BR, TR, TC); }
                if(!inVoxels[TA]){ Face(TA, TU, TC, TR); }

                if(!inVoxels[CL]){ Face(BA, BU, TU, TA); }
                if(!inVoxels[CD]){ Face(BR, BA, TA, TR); }
                if(!inVoxels[CB]){ Face(BA, BU, BC, BR); }
            }
        }
    }
};