How to update external model data to what it looks

Questions
,
1

Hello community !
I’m facing this problem and I tried to update external resources matrix or matrixWorld.
But it seems the performance is not what it meant to be.

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Figure1

Firgure 1 is scene set up,i’m doing csg with gltf model tank and box.
What i did looks like firgure2

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Figure2

It’s all messed up , I tried to update matrixes,but it’s not working.

new GLTFLoader().load('./resources/loader/tzz1/scene.gltf', gltf => {
	const g = new BoxGeometry(1, 1, 1)
	const brush1 = new Brush(g, new THREE.MeshLambertMaterial({
		transparent: true,
		opacity: 0.1
	}));
	brush1.position.y = 1
	brush1.updateMatrixWorld()

	this.scene.add(brush1)
						
	// figure2 code
	// gltf.scene.rotateX(0.5*Math.PI)
	this.scene.add(gltf.scene)

	gltf.scene.traverse(e => {
		if (e.isMesh) {
			e.geometry.scale(0.0005, 0.0005, 0.0005)
			e.updateMatrix()
			const brush2 = new Brush(e.geometry, new THREE.MeshLambertMaterial())
			const result = csgEvaluator.evaluate(brush2, brush1, SUBTRACTION);
			if (result) {
				e.geometry = result.geometry
			}
		}
	})
})

Thanks to gkjohnson lib,csg is now like really fast.And threejs of course!
Yet various external models have their own hierarchy , it’s a problem to me cause i have to deal with a dozen of external models , plus if each model has it’s own specific process, the codes will be too big.
Is there a way to update the transforms to what it looks like?