lighttroupe/luz

class VariableInputSliderImpulse < VariableInput
    title                "Slider Impulse"
    description "Treats slider input value as an upward impulse. The value falls back down to 0% according to a chosen gravity."

    categories :slider

    hint "Only registers a second impulse after the input value has returned to 0. Works well with MIDI drums which send the velocity of impact, then immediately send a 0 value."

    setting 'slider', :slider, :summary => true
    setting 'gravity_per_second', :float, :range => 0.0..5.0

    setting 'velocity_multiplier', :float, :range => 0.0..1.0, :default => 1.0..0.0

    def value
        @velocity ||= 0.0

        # add to velocity
        if slider > 0.0 and slider_setting.last_value == 0.0

            # stop all downward velocity on a hit (is this right?)
            #@velocity = 0.0 if @velocity < 0.0

            @velocity += (slider * velocity_multiplier)
        end

        # move output value by velocity
        v = (last_value + (@velocity * $env[:frame_time_delta])).clamp(0.0, 1.0)

        # hit the ceiling?
        if v == 1.0 and @velocity > 0.0
            @velocity = 0.0

        # hit the floor?
        elsif v == 0.0 and @velocity < 0.0
            @velocity = 0.0

        else
            # floating...
            @velocity -= (gravity_per_second * $env[:frame_time_delta]) if v > 0.0
        end

        return v
    end
end