ambient_occlusion.h

/********************************************************************
 * Copyright (C) 2015 Liangliang Nan <liangliang.nan@gmail.com>
 * https://3d.bk.tudelft.nl/liangliang/
 *
 * This file is part of Easy3D. If it is useful in your research/work,
 * I would be grateful if you show your appreciation by citing it:
 * ------------------------------------------------------------------
 *      Liangliang Nan.
 *      Easy3D: a lightweight, easy-to-use, and efficient C++ library
 *      for processing and rendering 3D data.
 *      Journal of Open Source Software, 6(64), 3255, 2021.
 * ------------------------------------------------------------------
 *
 * Easy3D is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License Version 3
 * as published by the Free Software Foundation.
 *
 * Easy3D is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 ********************************************************************/
 
#ifndef EASY_RENDERER_AMBIENT_OCCLUSION_H
#define EASY_RENDERER_AMBIENT_OCCLUSION_H
 
#include <vector>
#include <memory>
 
#include <easy3d/core/types.h>
 
 
namespace easy3d {
 
    class Model;
    class Camera;
    class FramebufferObject;

    class AmbientOcclusion
    {   
    public:
        explicit AmbientOcclusion(Camera* cam);
        virtual ~AmbientOcclusion();

        void  set_radius(float r) { radius_ = r; }
        float radius() const { return radius_; }

        void  set_bias(float b) { bias_ = b; }
        float bias() const { return bias_; }

        virtual unsigned int generate(const std::vector< std::shared_ptr<Model> >& models);
        unsigned int ssao_texture() const;
 
    protected:
        void init(int w, int h);
        void geometry_pass(const std::vector< std::shared_ptr<Model> >& models);
        void ssao_pass();
        void blur_pass();
        void generate_noise(int width, int height);
 
    protected:
        Camera* camera_;
 
        float   radius_;
        float   bias_;
 
        FramebufferObject* geom_fbo_;  
        FramebufferObject* ssao_fbo_;  
 
        std::vector<vec3> ssao_kernel_;     
        unsigned int      noise_texture_;   
 
    private:
        //copying disabled
        AmbientOcclusion(const AmbientOcclusion&);
        AmbientOcclusion& operator=(const AmbientOcclusion&);
    };
 
 
} // namespace easy3d
 
 
#endif  //  EASY_RENDERER_AMBIENT_OCCLUSION_H