
				img.width = displacementCanvas.width = visibleTextureCanvas.width = IMAGE_SIZE;
				img.height = displacementCanvas.height = visibleTextureCanvas.height = IMAGE_SIZE;
				displacementContext2D = displacementCanvas.getContext('2d');
				visibleCanvasContext2d = visibleTextureCanvas.getContext('2d');
				img.src = 'data:image/svg+xml;base64,' + btoa(document.querySelector('svg').outerHTML);
				await new Promise(resolve => img.onload = resolve);

				// load initial canvas, both depth and graphical overl