/* Copyright (c) 2022, NVIDIA CORPORATION. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *  * Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *  * Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *  * Neither the name of NVIDIA CORPORATION nor the names of its
 *    contributors may be used to endorse or promote products derived
 *    from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#ifndef __RENDER_PARTICLES__
#define __RENDER_PARTICLES__

#include <EGL/egl.h>
#include <EGL/eglext.h>
#include <GLES3/gl31.h>
#include <cstdio>

typedef float matrix4[4][4];
typedef float vector3[3];

// check for OpenGL errors
inline void checkGLErrors(const char *s)
{
    EGLenum error;

    while ((error = glGetError()) != GL_NO_ERROR) {
        fprintf(stderr, "%s: error - %d\n", s, error);
    }
}

class ParticleRenderer
{
public:
    ParticleRenderer(unsigned int windowWidth = 720, unsigned int windowHeight = 480);
    ~ParticleRenderer();

    void setPositions(float *pos, int numParticles);
    void setPositions(double *pos, int numParticles);
    void setBaseColor(float color[4]);
    void setColors(float *color, int numParticles);
    void setPBO(unsigned int pbo, int numParticles, bool fp64);

    enum DisplayMode { PARTICLE_POINTS, PARTICLE_SPRITES, PARTICLE_SPRITES_COLOR, PARTICLE_NUM_MODES };

    void display();

    void setPointSize(float size) { m_pointSize = size; }
    void setSpriteSize(float size) { m_spriteSize = size; }

    void setCameraPos(vector3 camera_pos)
    {
        m_camera[0] = camera_pos[0];
        m_camera[1] = camera_pos[1];
        m_camera[2] = camera_pos[2];
    }

    void resetPBO();

protected: // methods
    void _initGL();
    void _createTexture(int resolution);

protected: // data
    float  *m_pos;
    double *m_pos_fp64;
    int     m_numParticles;

    float   m_pointSize;
    float   m_spriteSize;
    vector3 m_camera;

    unsigned int m_vertexShader;
    unsigned int m_vertexShaderPoints;
    unsigned int m_fragmentShader;
    unsigned int m_programPoints;
    unsigned int m_programSprites;
    unsigned int m_texture;
    unsigned int m_pbo;
    unsigned int m_vboColor;
    unsigned int m_windowWidth;
    unsigned int m_windowHeight;

    float m_baseColor[4];

    bool m_bFp64Positions;
};

#endif //__ RENDER_PARTICLES__
