How ot get vertices, faces, faceVertexUvs from bufferGeometry

Questions
1

Hi ,
Before:
> let bufferGeometry = this.mesh.getObject3d().geometry;
> let geometry = new THREE.Geometry().fromBufferGeometry(bufferGeometry);
> let { vertices, faces, faceVertexUvs } = geometry;
now,use r125, there is any other good way to get ?
Thanks!

2

Hi!
BufferGeometry has different structure from Geometry.
Vertices: geometry.attributes.position.
Faces: if your geometry has no index, then a face defined by three consequent vertices, otherwise, by three consequent indices of vertices in index.
UVs: geometry.attributes.uv

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3 
		
	function isIndexed(mesh) {
 		return mesh.geometry.index != null;
 	}
 	
 	function getFaces(mesh) {
 		const faces = [];
 		const position = mesh.geometry.getAttribute( 'position' );
 		
 		if (isIndexed(mesh)) {
			const index = mesh.geometry.getIndex();
			
			for ( let i = 0; i < index.count; i += 3 ) {
				const face = {
					a: index.getX(i),
					b: index.getX(i+1),
					c: index.getX(i+2),
					normal: new Vector3()
				};
				faces.push(face);
			}
 		}
 		else {
			for ( let i = 0; i < position.count; i += 3 ) {
				const face = {
					a: i,
					b: i+1,
					c: i+2
				};
				faces.push(face);
			}
 		}
 		
 		
		for( let j = 0; j < faces.length; j ++ ) {
			let pointA = new Vector3(
				position.getX(face.a),
				position.getY(face.a),
				position.getZ(face.a)
			);
			let pointB = new Vector3(
				position.getX(face.b),
				position.getY(face.b),
				position.getZ(face.b)
			);
			let pointC = new Vector3(
				position.getX(face.c),
				position.getY(face.c),
				position.getZ(face.c)
			);
			
			let faceTriangule = new Triangule(
				pointA,
				pointB,
				pointC
			);
			
			faceTriangule.getNormal(faces[j].normal);
		}
 		
 		return faces;
 	}
 	
 	function getVertices(mesh) {
 		const position = mesh.geometry.getAttribute( 'position' );
 		const vertices = [];
 		
 		for ( let i = 0; i < position.count / position.itemSize; i++ ) {
			const vertex = new Vector3(
				position.getX(i),
				position.getY(i),
				position.getZ(i)
			);
			
			vertices.push(vertex);
		}
		
		return vertices;
 	}
 	
 	function getFaceVertexUvs(mesh) {
 		const faceVertexUvs = [];
 		const uv = mesh.geometry.getAttribute( 'uv' );
 		
 		if (isIndexed(mesh)) {
			const index = mesh.geometry.getIndex();
			
			for ( let i = 0; i < index.count; i += 3 ) {
				const faceVertexUv = [
					new Vector2(
						uv.getX( index.getX(i) ),
						uv.getY( index.getX(i) )
					),
					new Vector2(
						uv.getX( index.getX(i+1) ),
						uv.getY( index.getX(i+1) )
					),
					new Vector2(
						uv.getX( index.getX(i+2) ),
						uv.getY( index.getX(i+2) )
					)
				];
				
				faceVertexUvs.push(faceVertexUv);
			}
 		}
 		else {
			for ( let i = 0; i < uv.count; i += 3 ) {
				const faceVertexUv = [
					new Vector2(
						uv.getX(i),
						uv.getY(i)
					),
					new Vector2(
						uv.getX(i+1),
						uv.getY(i+1)
					),
					new Vector2(
						uv.getX(i+2),
						uv.getY(i+2)
					)
				];
				
				faceVertexUvs.push(faceVertexUv);
			}
 		}
 		
 		return faceVertexUvs;
 	}
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