openrw/rwengine/include/render/VisualFX.hpp

#pragma once

#include <glm/glm.hpp>
#include <gl/TextureData.hpp>

/**
 * Represents a scene effect: lighting, particles etc.
 */
class VisualFX
{
public:
	enum EffectType
	{
		Light,
		Particle,
		Trail
	};
	
	struct LightData
	{
		~LightData();
	};
	struct ParticleData
	{
		/** Initial world position */
		glm::vec3 position;

		/** Direction of particle */
		glm::vec3 direction;

		/** Particle orientation modes */
		enum Orientation {
			Free, /** faces direction using up */
			Camera, /** Faces towards the camera @todo implement */
			UpCamera /** Face closes point in camera's look direction */
		};
		Orientation orientation;

		/** Game time at particle instantiation */
		float starttime;
		/** Number of seconds particle should exist for, negative values = forever */
		float lifetime;

		/** Texture name */
		TextureData::Handle texture;

		/** Size of particle */
		glm::vec2 size;

		/** Up direction (only used in Free mode) */
		glm::vec3 up;

		/** Render tint colour */
		glm::vec4 colour;

		/** Constructs a particle */
		ParticleData()
			: orientation(Free), starttime(0.f), lifetime(-1.f), size(1.f, 1.f),
			  up(0.f, 0.f, 1.f), colour(1.f, 1.f, 1.f, 1.f) { }
		~ParticleData();
	};
	struct TrailData
	{
		~TrailData();
	};
	
	/// @todo stop abusing unions
	union {
		LightData light;
		ParticleData particle;
		TrailData trail;
	};
	
	VisualFX(EffectType type);
	~VisualFX();
	
	EffectType getType() const { return type; }
	
	const glm::vec3& getPosition() const;
	
private:
	EffectType type;
};