particles

type ConeSpawner struct {
	BottomRadius float32
	TopRadius    float32
	Length       float32
	Owner        *Emitter
	// contains filtered or unexported fields
}

type CubeSpawner struct {
	BottomLeft mgl.Vec3
	TopRight   mgl.Vec3
	Owner      *Emitter
	// contains filtered or unexported fields
}

type Emitter struct {
	Owner      *System
	Particles  []Particle
	Texture    graphics.Texture
	Shader     graphics.Program
	Properties EmitterProperties
	Spawner    ParticleSpawner
	// contains filtered or unexported fields
}

type EmitterProperties struct {
	TextureFilepath string
	MaxParticles    uint
	SpawnRate       uint     // particles per second
	Velocity        mgl.Vec3 // should be normalized
	Speed           float32
	Acceleration    mgl.Vec3
	TTL             float64  // in seconds
	Origin          mgl.Vec3 // relative to Emitter.Owner.Origin
	Rotation        mgl.Quat
	Color           mgl.Vec4
	Size            float32
}

type Particle struct {
	Size         float32
	Color        mgl.Vec4
	Location     mgl.Vec3
	Velocity     mgl.Vec3 // should be normalized
	Speed        float32
	Acceleration mgl.Vec3
	EndTime      float64
	StartTime    float64
}

type ParticleSpawner interface {
	// NewParticle creates a new particle for the emitter
	NewParticle() Particle

	// DrawSpawnVolume draws an object on screen, probably a wireframe object, representing the spawn volume
	DrawSpawnVolume(r renderer.Renderer, shader *fizzle.RenderShader, projection mgl.Mat4, view mgl.Mat4, camera fizzle.Camera)

	// GetLocation returns the location of the spawner
	GetLocation() mgl.Vec3

	// GetName returns a user friendly name for the spawner
	GetName() string

	// SetOwner sets the owning emitter for the spawner
	SetOwner(e *Emitter)

	// CreateRenderable creates a cached renderable for the spawner that represents
	// the spawning volume for particles.
	CreateRenderable() *fizzle.Renderable
}

type System struct {
	Emitters   []*Emitter
	Origin     mgl.Vec3
	IsActive   bool
	IsEmitting bool
	// contains filtered or unexported fields
}