three.js/src/objects/InstancedMesh.d.ts

import { Geometry } from './../core/Geometry';
import { BufferGeometry } from '../core/BufferGeometry';
import { Material } from './../materials/Material';
import { BufferAttribute } from './../core/BufferAttribute';
import { Mesh } from './Mesh';
import { Matrix4 } from './../math/Matrix4';
import { Color } from './../math/Color';

export class InstancedMesh <
	TGeometry extends Geometry | BufferGeometry = Geometry | BufferGeometry,
	TMaterial extends Material | Material[] = Material | Material[]
> extends Mesh<TGeometry, TMaterial> {

	constructor(
		geometry: TGeometry,
		material: TMaterial,
		count: number
	);

	count: number;
	instanceColor: null | BufferAttribute;
	instanceMatrix: BufferAttribute;
	readonly isInstancedMesh: true;

	getColorAt( index: number, color: Color ): void;
	getMatrixAt( index: number, matrix: Matrix4 ): void;
	setColorAt( index: number, color: Color ): void;
	setMatrixAt( index: number, matrix: Matrix4 ): void;
	dispose(): void;

}