#pragma once

#include "effects/video_effect.hpp"

namespace effector {

// The feedback effect in motion: the picture nested inside itself, each copy
// smaller, turned and drifted further than the one around it, and the whole
// stack flying inwards (or outwards) without end.
//
// A copy sits at a depth, and its size, turn and drift follow from that depth
// alone. Every frame moves each copy on by part of one step, so after a whole
// cycle each copy lies exactly where its neighbour started: a new one fades
// in at the far end while the nearest fades out into the picture itself, and
// the clip loops without a jump.
class TunnelEffect : public VideoEffect {
public:
    std::string name() const override { return "tunnel"; }
    std::string title() const override { return "Echo tunnel"; }
    std::string description() const override {
        return "Nests the picture inside itself, as Feedback does, and flies through the echoes "
               "without end.";
    }
    const std::vector<ParamSpec>& params() const override;

protected:
    Image animate(Image input, const ParamValues& values, const Moment& at) const override;
};

}  // namespace effector