Chapter 9: Mesh

Core Idea

Class representing triangular polygon mesh based objects.

Key Concepts

• count : number: The number of instances of this mesh. Can only be used with WebGPURenderer.
• geometry : BufferGeometry: The mesh geometry.
• isMesh : boolean (readonly): This flag can be used for type testing.
• material : Material | Array.<Material>: The mesh material.
• morphTargetDictionary : Object.<string, number> | undefined: A dictionary representing the morph targets in the geometry. The key is the morph targets name, the value its attribute index. This member …
• morphTargetInfluences : Array.<number> | undefined: An array of weights typically in the range [0,1] that specify how much of the morph is applied. This member is undefined by default and…

Code Examples

const geometry = new THREE.BoxGeometry( 1, 1, 1 );
const material = new THREE.MeshBasicMaterial( { color: 0xffff00 } );
const mesh = new THREE.Mesh( geometry, material );
scene.add( mesh );

• What it demonstrates: Typical usage of Mesh.

Reference Tables

Constructor

Signature
`new Mesh( geometry : BufferGeometry, material : Material

Properties

Property	Description
.count : number	The number of instances of this mesh. Can only be used with WebGPURenderer.
.geometry : BufferGeometry	The mesh geometry.
.isMesh : boolean (readonly)	This flag can be used for type testing.
`.material : Material	Array.<Material>`
`.morphTargetDictionary : Object.<string, number>	undefined`
`.morphTargetInfluences : Array.<number>	undefined`

Methods

Method	Description
.getVertexPosition( index : number, target : Vector3 ) : Vector3	Returns the local-space position of the vertex at the given index, taking into account the current animation state of both morph targets and skinning.
.raycast( raycaster : Raycaster, intersects : Array.<Object> )	Computes intersection points between a casted ray and this line.
.updateMorphTargets()	Sets the values of Mesh#morphTargetDictionary and Mesh#morphTargetInfluences to make sure existing morph targets can influence th…

Key Takeaways

1. Mesh extends: EventDispatcher → Object3D
2. Most relevant properties: count, geometry, isMesh, material.
3. Key methods: getVertexPosition, raycast, updateMorphTargets.

Connects To

• EventDispatcher: parent class
• Object3D: parent class
• Source: src/objects/Mesh.js