lighttroupe/luz

class ActorEffectInspect < ActorEffect
    title                'Inspect'
    description "Zoom in and pan on an actor while keeping it entirely on screen."

    category :transform

    setting 'zoom', :float, :default => 1.0..2.0
    setting 'x', :float, :range => -0.5..0.5, :default => 0.0..0.5
    setting 'y', :float, :range => -0.5..0.5, :default => 0.0..0.5

    def render
        # When zoom is 1.0, we can't translate at all.
        # When zoom is 2.0, we can translate exactly 0.5.
        # When zoom is 3.0, we must translate 1.0 to reach the border, etc.
        with_translation(-x * (zoom - 1.0), -y * (zoom - 1.0)) {        # NOTE: negate x and y because they mean "go" and not "move"
            with_scale(zoom) {
                yield
            }
        }
    end
end