func New(filename string, sprite sprite.Sprite, a ...interface{}) *ParticleSystem {
ps := new(ParticleSystem)
if len(a) == 1 {
if fps, ok := a[0].(float64); ok {
if fps != 0.0 {
ps.updateSpeed = 1.0 / fps
}
}
}
ps.h = hge.New()
ps.rand = rand.New(int(timer.Time()))
ps.rand.Seed()
ptr := resource.LoadBytes(filename)
if ptr == nil {
ps.h.Log("Particle file (%s) seems to be empty.", filename)
return nil
}
// skip the first four bytes
i := uintptr(4)
// Ok, First we reflect the ParticleSystemInfo struct
s := reflect.ValueOf(&ps.Info).Elem()
// Then we loop through each element, skipping sprite for obvious reasons
for j := 1; j < s.NumField(); j++ {
// Then we get the field of the struct
f := s.Field(j)
// Here we examine the type
switch f.Type().String() {
case "float64":
// Then we set the structure's field to the value at the current
// byte(s)
// We cast the value pointed to by the ptr[i] with unsafe.Pointer
f.SetFloat(float64(*(*float32)(cast(&ptr[i]))))
// Next we skip ahead based on the size of the data read
i += unsafe.Sizeof(float32(0.0))
case "int":
f.SetInt(int64(*(*int32)(cast(&ptr[i]))))
i += unsafe.Sizeof(int32(0))
case "bool":
f.SetBool(*(*bool)(cast(&ptr[i])))
i += unsafe.Sizeof(bool(false))
i += 3 // padding
case "color.ColorRGB":
for k := 0; k < 4; k++ {
f.Field(k).SetFloat(float64(*(*float32)(cast(&ptr[i]))))
i += unsafe.Sizeof(float32(0.0))
}
}
}
ps.Info.Sprite = sprite
ps.age = -2.0
ps.particles = make([]particle, hgeMAX_PARTICLES+1)
return ps
}
func (h *HGE) Timer_GetTime() float64 {
return timer.Time()
}