📄 VertexNormalsHelper.js¶
📊 Analysis Summary¶
| Metric | Count |
|---|---|
| 🔧 Functions | 2 |
| 🧱 Classes | 1 |
| 📦 Imports | 6 |
| 📊 Variables & Constants | 12 |
📚 Table of Contents¶
🛠️ File Location:¶
📂 examples/jsm/helpers/VertexNormalsHelper.js
📦 Imports¶
| Name | Source |
|---|---|
BufferGeometry |
three |
Float32BufferAttribute |
three |
LineSegments |
three |
LineBasicMaterial |
three |
Matrix3 |
three |
Vector3 |
three |
Variables & Constants¶
| Name | Type | Kind | Value | Exported |
|---|---|---|---|---|
_v1 |
any |
let/var | new Vector3() |
✗ |
_v2 |
any |
let/var | new Vector3() |
✗ |
_normalMatrix |
any |
let/var | new Matrix3() |
✗ |
geometry |
any |
let/var | new BufferGeometry() |
✗ |
nNormals |
any |
let/var | object.geometry.attributes.normal.count |
✗ |
positions |
any |
let/var | new Float32BufferAttribute( nNormals * 2 * 3, 3 ) |
✗ |
matrixWorld |
any |
let/var | this.object.matrixWorld |
✗ |
position |
any |
let/var | this.geometry.attributes.position |
✗ |
objGeometry |
any |
let/var | this.object.geometry |
✗ |
objPos |
any |
let/var | objGeometry.attributes.position |
✗ |
objNorm |
any |
let/var | objGeometry.attributes.normal |
✗ |
idx |
number |
let/var | 0 |
✗ |
Functions¶
VertexNormalsHelper.update(): void¶
JSDoc:
Returns: void
Calls:
this.object.updateMatrixWorld_normalMatrix.getNormalMatrix_v1.fromBufferAttribute( objPos, j ).applyMatrix4_v2.fromBufferAttribute_v2.applyMatrix3( _normalMatrix ).normalize().multiplyScalar( this.size ).addposition.setXYZ
Internal Comments:
Code
update() {
this.object.updateMatrixWorld( true );
_normalMatrix.getNormalMatrix( this.object.matrixWorld );
const matrixWorld = this.object.matrixWorld;
const position = this.geometry.attributes.position;
//
const objGeometry = this.object.geometry;
if ( objGeometry ) {
const objPos = objGeometry.attributes.position;
const objNorm = objGeometry.attributes.normal;
let idx = 0;
// for simplicity, ignore index and drawcalls, and render every normal
for ( let j = 0, jl = objPos.count; j < jl; j ++ ) {
_v1.fromBufferAttribute( objPos, j ).applyMatrix4( matrixWorld );
_v2.fromBufferAttribute( objNorm, j );
_v2.applyMatrix3( _normalMatrix ).normalize().multiplyScalar( this.size ).add( _v1 );
position.setXYZ( idx, _v1.x, _v1.y, _v1.z );
idx = idx + 1;
position.setXYZ( idx, _v2.x, _v2.y, _v2.z );
idx = idx + 1;
}
}
position.needsUpdate = true;
}
VertexNormalsHelper.dispose(): void¶
JSDoc:
/**
* Frees the GPU-related resources allocated by this instance. Call this
* method whenever this instance is no longer used in your app.
*/
Returns: void
Calls:
this.geometry.disposethis.material.dispose
Classes¶
VertexNormalsHelper¶
Class Code
class VertexNormalsHelper extends LineSegments {
/**
* Constructs a new vertex normals helper.
*
* @param {Object3D} object - The object for which to visualize vertex normals.
* @param {number} [size=1] - The helper's size.
* @param {number|Color|string} [color=0xff0000] - The helper's color.
*/
constructor( object, size = 1, color = 0xff0000 ) {
const geometry = new BufferGeometry();
const nNormals = object.geometry.attributes.normal.count;
const positions = new Float32BufferAttribute( nNormals * 2 * 3, 3 );
geometry.setAttribute( 'position', positions );
super( geometry, new LineBasicMaterial( { color, toneMapped: false } ) );
/**
* The object for which to visualize vertex normals.
*
* @type {Object3D}
*/
this.object = object;
/**
* The helper's size.
*
* @type {number}
* @default 1
*/
this.size = size;
this.type = 'VertexNormalsHelper';
/**
* Overwritten and set to `false` since the object's world transformation
* is encoded in the helper's geometry data.
*
* @type {boolean}
* @default false
*/
this.matrixAutoUpdate = false;
/**
* This flag can be used for type testing.
*
* @type {boolean}
* @readonly
* @default true
*/
this.isVertexNormalsHelper = true;
this.update();
}
/**
* Updates the vertex normals preview based on the object's world transform.
*/
update() {
this.object.updateMatrixWorld( true );
_normalMatrix.getNormalMatrix( this.object.matrixWorld );
const matrixWorld = this.object.matrixWorld;
const position = this.geometry.attributes.position;
//
const objGeometry = this.object.geometry;
if ( objGeometry ) {
const objPos = objGeometry.attributes.position;
const objNorm = objGeometry.attributes.normal;
let idx = 0;
// for simplicity, ignore index and drawcalls, and render every normal
for ( let j = 0, jl = objPos.count; j < jl; j ++ ) {
_v1.fromBufferAttribute( objPos, j ).applyMatrix4( matrixWorld );
_v2.fromBufferAttribute( objNorm, j );
_v2.applyMatrix3( _normalMatrix ).normalize().multiplyScalar( this.size ).add( _v1 );
position.setXYZ( idx, _v1.x, _v1.y, _v1.z );
idx = idx + 1;
position.setXYZ( idx, _v2.x, _v2.y, _v2.z );
idx = idx + 1;
}
}
position.needsUpdate = true;
}
/**
* Frees the GPU-related resources allocated by this instance. Call this
* method whenever this instance is no longer used in your app.
*/
dispose() {
this.geometry.dispose();
this.material.dispose();
}
}
Methods¶
update(): void¶
Code
update() {
this.object.updateMatrixWorld( true );
_normalMatrix.getNormalMatrix( this.object.matrixWorld );
const matrixWorld = this.object.matrixWorld;
const position = this.geometry.attributes.position;
//
const objGeometry = this.object.geometry;
if ( objGeometry ) {
const objPos = objGeometry.attributes.position;
const objNorm = objGeometry.attributes.normal;
let idx = 0;
// for simplicity, ignore index and drawcalls, and render every normal
for ( let j = 0, jl = objPos.count; j < jl; j ++ ) {
_v1.fromBufferAttribute( objPos, j ).applyMatrix4( matrixWorld );
_v2.fromBufferAttribute( objNorm, j );
_v2.applyMatrix3( _normalMatrix ).normalize().multiplyScalar( this.size ).add( _v1 );
position.setXYZ( idx, _v1.x, _v1.y, _v1.z );
idx = idx + 1;
position.setXYZ( idx, _v2.x, _v2.y, _v2.z );
idx = idx + 1;
}
}
position.needsUpdate = true;
}