// Update ticks all Entity animations for the time since last frame
func (self *Animation) Update(deltaT float32) {
var animation *components.Animation
var handler animationHandler
var ok bool
for _, entity := range self.entitySet.Entities() {
animation = components.GetAnimation(entity)
handler, ok = animationHandlers[animation.PropertyName]
if !ok {
log.Panicf("[Animation] No animation handler defined for %s\n", animation.PropertyName)
}
if handler(deltaT, entity) {
animation.Finish()
entity.RemoveComponent(components.ANIMATION)
}
}
}
// Simple linear animation between two positions over time
func animatePosition(deltaT float32, entity *core.Entity) bool {
animation := components.GetAnimation(entity)
transform := components.GetTransform(entity)
// Move more of this into the Animation?
// Basically we are building this to figure out the distance we need to travel
// in the current tick to have consistent, linear movement over the time period requested.
// Probably better ways of calculating this.
if animation.CurrentTweenTick == 0 {
animation.TweenStartAt = transform.Position
}
animation.CurrentTweenTick += deltaT
tweenPercent := deltaT / animation.TweenTime
movePerFrame := animation.TweenTo.Sub(animation.TweenStartAt).Scale(tweenPercent)
transform.Position = transform.Position.Add(movePerFrame)
return animation.CurrentTweenTick >= animation.TweenTime
}