SurfaceAlignedParticleGroup.h

#pragma once
#include "SurfaceAlignedParticle.h"
#include "IParticleGroup.h"
#include "Texture.h"
#include "ParticleRenderer.h"
#include "HalfedgeMesh.h"
#include "SurfaceAlignedParticleGroupProperties.h"

class ParticleManager;

class SurfaceAlignedParticleGroup : public virtual IParticleGroup
{
public:
    //TODO add faceNormal
    SurfaceAlignedParticleGroup(std::string name);
    ~SurfaceAlignedParticleGroup();
    
    void addParticle(SurfaceAlignedParticle* particle);
    void addParticles(std::vector<SurfaceAlignedParticle*> particles);

    //IRenderable
    void initialize();
    void bindResources(const Shader * shader);  
    void unbindResources();
    void draw();    

    //IParticleGroup
    void update();
    int numberAlive();
    void spawn(int i);
    void ensureCapacity(int size);

    int size(); void updateWithProperties(SurfaceAlignedParticleGroupProperties* props);
private:
    std::vector<SurfaceAlignedParticle*> _particles;    
    
    GLuint _vao;
    GLuint _vboPositions;
    GLuint _vboHalfSizes;
    GLuint _vboDirections;
    GLuint _vboParticleColors;
    //TODO: When particles are binned per face, it is not necessary to pass one normal per particle but one normal per face!
    GLuint _vboFaceNormals;

    unsigned _numberOfAliveParticles = 0;
    unsigned _waitingForSpawn = 0;
    
};