var scale by remember { mutableStateOf(1f) }
var canvasOffset by remember { mutableStateOf(Offset.Zero) }
val rectangles = remember { mutableStateListOf<Offset>() }

Box(
    Modifier.windowObject()
        .fillMaxWidth(0.8f)
        .fillMaxHeight()
        .background(MaterialTheme.colors.surface)
        .onPointerEvent(PointerEventType.Scroll) {
			// Mouse scroll to zoom in and out
            scale = (scale * exp(-it.changes.first().scrollDelta.y.toInt().sign * 0.2f)).coerceIn(0.25f, 1.75f)
        }.pointerInput(Unit) {
            detectDragGestures(
                matcher = PointerMatcher.mouse(PointerButton.Tertiary),
                onDrag = { dragAmount ->
					// Middle click move canvas
                    canvasOffset += dragAmount
                }
            )
        }.pointerInput(Unit) {
            detectTapGestures(matcher = PointerMatcher.mouse(PointerButton.Secondary)) { clickLocation ->
				// Right click to add a rectangle
                rectangles.add(clickLocation - canvasOffset)
            }
        }
) {

    Canvas(
        modifier = Modifier
            .fillMaxSize()
            .clipToBounds()
            .graphicsLayer(
                scaleX = scale,
                scaleY = scale,
                translationX = canvasOffset.x,
                translationY = canvasOffset.y,
            )
    ) {

        rectangles.forEach { rect ->
            drawRect(
                topLeft = rect,
                color = Color.Red,
                size = Size(100f, 100f)
            )
        }
    }
}