EchoCopy
class EchoCopy(val zoom: Float = 1.0f, val angle: Float = 0.0f, val mirrorX: Boolean = false, val mirrorY: Boolean = false, val share: Float = 0.3f)
A second copy of the last frame, scaled by zoom, turned by angle radians and mirrored. share is taken out of the trail, so what comes back still totals less than one.