updateGeometry() {

		const extracted = this.volume.extractPerpendicularPlane( this.axis, this.index );
		this.sliceAccess = extracted.sliceAccess;
		this.jLength = extracted.jLength;
		this.iLength = extracted.iLength;
		this.matrix = extracted.matrix;

		this.canvas.width = extracted.planeWidth;
		this.canvas.height = extracted.planeHeight;
		this.canvasBuffer.width = this.iLength;
		this.canvasBuffer.height = this.jLength;
		this.ctx = this.canvas.getContext( '2d' );
		this.ctxBuffer = this.canvasBuffer.getContext( '2d' );

		if ( this.geometry ) this.geometry.dispose(); // dispose existing geometry

		this.geometry = new PlaneGeometry( extracted.planeWidth, extracted.planeHeight );

		if ( this.mesh ) {

			this.mesh.geometry = this.geometry;
			//reset mesh matrix
			this.mesh.matrix.identity();
			this.mesh.applyMatrix4( this.matrix );

		}

		this.geometryNeedsUpdate = false;

	}
Refresh the geometry according to axis and index.
@see {@link Volume#extractPerpendicularPlane}