func (this *Camera) RotateY(angle float64) {
yaxis := this.Up
mrot := mat4.RotationAxis(yaxis, angle)
this.Dir = mrot.Mulv(this.Dir)
}
func (this *Camera) RotateX(angle float64) {
xaxis := this.Dir.Cross(this.Up)
mrot := mat4.RotationAxis(xaxis, angle)
this.Dir = mrot.Mulv(this.Dir)
}