Figured it out; replace drawImage in the tutorial with:

val painter = painterResource(R...)
val size = Size(width = ..., height = ...)
with(painter) {
  drawIntoCanvas { canvas ->
    val paint = Paint()
    paint.blendMode = BlendMode.DstIn
    canvas.withSaveLayer(Rect(Offset.Zero, size), paint) { draw(size) }
  }
}