//
//  ToneMappingEffect.h
//  libraries/render-utils/src
//
//  Created by Sam Gateau on 12/7/2015.
//  Copyright 2015 High Fidelity, Inc.
//
//  Distributed under the Apache License, Version 2.0.
//  See the accompanying file LICENSE or http://www.apache.org/licenses/LICENSE-2.0.html
//

#ifndef hifi_ToneMappingEffect_h
#define hifi_ToneMappingEffect_h

#include <DependencyManager.h>
#include <NumericalConstants.h>

#include <gpu/Resource.h>
#include <gpu/Pipeline.h>

class RenderArgs;

class ToneMappingEffect {
public:
    ToneMappingEffect();
    virtual ~ToneMappingEffect() {}

    void render(RenderArgs* args);

    void setExposure(float exposure);
    float getExposure() const { return _parametersBuffer.get<Parameters>()._exposure; }

    // Different tone curve available
    enum ToneCurve {
        None = 0,
        Gamma22,
        Reinhard,
        Filmic,
    };
    void setToneCurve(ToneCurve curve);
    ToneCurve getToneCurve() const { return (ToneCurve)_parametersBuffer.get<Parameters>()._toneCurve; }

private:

    gpu::PipelinePointer _blitLightBuffer;

    // Class describing the uniform buffer with all the parameters common to the tone mapping shaders
    class Parameters {
    public:
        float _exposure = 0.0f;
        float _twoPowExposure = 1.0f;
        glm::vec2 spareA;
        int _toneCurve = Filmic;
        glm::vec3 spareB;

        Parameters() {}
    };
    typedef gpu::BufferView UniformBufferView;
    gpu::BufferView _parametersBuffer;

    void init();
};

#endif // hifi_ToneMappingEffect_h