fireball/lib/geometries/BoxGeometry.js

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2018-12-25 13:59:22 +00:00
/**
* @author mrdoob / http://mrdoob.com/
* @author Mugen87 / https://github.com/Mugen87
*/
import { Geometry } from '../core/Geometry.js';
import { BufferGeometry } from '../core/BufferGeometry.js';
import { Float32BufferAttribute } from '../core/BufferAttribute.js';
import { Vector3 } from '../math/Vector3.js';
// BoxGeometry
function BoxGeometry( width, height, depth, widthSegments, heightSegments, depthSegments ) {
Geometry.call( this );
this.type = 'BoxGeometry';
this.parameters = {
width: width,
height: height,
depth: depth,
widthSegments: widthSegments,
heightSegments: heightSegments,
depthSegments: depthSegments
};
this.fromBufferGeometry( new BoxBufferGeometry( width, height, depth, widthSegments, heightSegments, depthSegments ) );
this.mergeVertices();
}
BoxGeometry.prototype = Object.create( Geometry.prototype );
BoxGeometry.prototype.constructor = BoxGeometry;
// BoxBufferGeometry
function BoxBufferGeometry( width, height, depth, widthSegments, heightSegments, depthSegments ) {
BufferGeometry.call( this );
this.type = 'BoxBufferGeometry';
this.parameters = {
width: width,
height: height,
depth: depth,
widthSegments: widthSegments,
heightSegments: heightSegments,
depthSegments: depthSegments
};
var scope = this;
width = width || 1;
height = height || 1;
depth = depth || 1;
// segments
widthSegments = Math.floor( widthSegments ) || 1;
heightSegments = Math.floor( heightSegments ) || 1;
depthSegments = Math.floor( depthSegments ) || 1;
// buffers
var indices = [];
var vertices = [];
var normals = [];
var uvs = [];
// helper variables
var numberOfVertices = 0;
var groupStart = 0;
// build each side of the box geometry
buildPlane( 'z', 'y', 'x', - 1, - 1, depth, height, width, depthSegments, heightSegments, 0 ); // px
buildPlane( 'z', 'y', 'x', 1, - 1, depth, height, - width, depthSegments, heightSegments, 1 ); // nx
buildPlane( 'x', 'z', 'y', 1, 1, width, depth, height, widthSegments, depthSegments, 2 ); // py
buildPlane( 'x', 'z', 'y', 1, - 1, width, depth, - height, widthSegments, depthSegments, 3 ); // ny
buildPlane( 'x', 'y', 'z', 1, - 1, width, height, depth, widthSegments, heightSegments, 4 ); // pz
buildPlane( 'x', 'y', 'z', - 1, - 1, width, height, - depth, widthSegments, heightSegments, 5 ); // nz
// build geometry
this.setIndex( indices );
this.addAttribute( 'position', new Float32BufferAttribute( vertices, 3 ) );
this.addAttribute( 'normal', new Float32BufferAttribute( normals, 3 ) );
this.addAttribute( 'uv', new Float32BufferAttribute( uvs, 2 ) );
function buildPlane( u, v, w, udir, vdir, width, height, depth, gridX, gridY, materialIndex ) {
var segmentWidth = width / gridX;
var segmentHeight = height / gridY;
var widthHalf = width / 2;
var heightHalf = height / 2;
var depthHalf = depth / 2;
var gridX1 = gridX + 1;
var gridY1 = gridY + 1;
var vertexCounter = 0;
var groupCount = 0;
var ix, iy;
var vector = new Vector3();
// generate vertices, normals and uvs
for ( iy = 0; iy < gridY1; iy ++ ) {
var y = iy * segmentHeight - heightHalf;
for ( ix = 0; ix < gridX1; ix ++ ) {
var x = ix * segmentWidth - widthHalf;
// set values to correct vector component
vector[ u ] = x * udir;
vector[ v ] = y * vdir;
vector[ w ] = depthHalf;
// now apply vector to vertex buffer
vertices.push( vector.x, vector.y, vector.z );
// set values to correct vector component
vector[ u ] = 0;
vector[ v ] = 0;
vector[ w ] = depth > 0 ? 1 : - 1;
// now apply vector to normal buffer
normals.push( vector.x, vector.y, vector.z );
// uvs
uvs.push( ix / gridX );
uvs.push( 1 - ( iy / gridY ) );
// counters
vertexCounter += 1;
}
}
// indices
// 1. you need three indices to draw a single face
// 2. a single segment consists of two faces
// 3. so we need to generate six (2*3) indices per segment
for ( iy = 0; iy < gridY; iy ++ ) {
for ( ix = 0; ix < gridX; ix ++ ) {
var a = numberOfVertices + ix + gridX1 * iy;
var b = numberOfVertices + ix + gridX1 * ( iy + 1 );
var c = numberOfVertices + ( ix + 1 ) + gridX1 * ( iy + 1 );
var d = numberOfVertices + ( ix + 1 ) + gridX1 * iy;
// faces
indices.push( a, b, d );
indices.push( b, c, d );
// increase counter
groupCount += 6;
}
}
// add a group to the geometry. this will ensure multi material support
scope.addGroup( groupStart, groupCount, materialIndex );
// calculate new start value for groups
groupStart += groupCount;
// update total number of vertices
numberOfVertices += vertexCounter;
}
}
BoxBufferGeometry.prototype = Object.create( BufferGeometry.prototype );
BoxBufferGeometry.prototype.constructor = BoxBufferGeometry;
export { BoxGeometry, BoxBufferGeometry };