mesh_instancer.h

#pragma once
 
#include <unordered_map>
 
#include "../generic/identifiable.h"
 
#include "stage_node.h"
#include "../interfaces.h"
#include "../sound.h"
#include "../generic/manual_object.h"
#include "../generic/containers/contiguous_map.h"
 
namespace smlt {
 
typedef std::size_t MeshInstanceID;
 
class MeshInstancer:
    public TypedDestroyableObject<MeshInstancer, Stage>,
    public StageNode,
    public virtual Boundable,
    public generic::Identifiable<MeshInstancerID>,
    public AudioSource,
    public HasMutableRenderPriority,
    public ChainNameable<MeshInstancer> {
 
public:
    MeshInstancer(Stage* stage, SoundDriver* sound_driver, MeshPtr mesh);
    virtual ~MeshInstancer();
 
    const AABB& aabb() const override;
    void set_mesh(MeshPtr mesh);
    MeshPtr mesh() const;
 
    MeshInstanceID new_mesh_instance(
        const smlt::Vec3& position,
        const smlt::Quaternion& rotation=smlt::Quaternion()
    );
 
    bool destroy_mesh_instance(MeshInstanceID mid);
 
    bool show_mesh_instance(MeshInstanceID mid);
 
    bool hide_mesh_instance(MeshInstanceID mid);
 
    void _get_renderables(
        batcher::RenderQueue* render_queue,
        const CameraPtr camera,
        const DetailLevel detail_level
    ) override;
private:
    MeshPtr mesh_;
 
    /* The axis-aligned box containing all mesh instances */
    AABB aabb_;
 
    void recalc_aabb();    
 
    void on_transformation_changed();
 
    struct MeshInstance {
        uint32_t id = 0;
        bool is_visible = true;
        Mat4 transformation;
        Mat4 abs_transformation;
        AABB aabb;
 
        /* Recalc the aabb from the transformation */
        void recalc_aabb(MeshPtr mesh);
    };
 
    static uint32_t id_counter_;
 
    /* FIXME: Convert to ContiguousMap when it has erase... */
    std::unordered_map<uint32_t, MeshInstance> instances_;
};
 
 
}