Applying Textures and Simple Animations to Our Scene - WebGL Game Development - page 230

When the Grenade animation finishes, it invokes the explosionCallBack function
and passes its modelMatrix as shown in the following code:
Grenade.prototype.update=function() {
if(this.counter<this.positions.length-1){
...
}
else{
...
if(this.explosionCallBack!=null){
this.explosionCallBack(this.modelMatrix);
}
}
}
Let's walk through the implementation of the preceding classes in 06-Grenade-
Action-Blast.html .
We have added a new variable to hold the explosion object, as shown in the
following code:
var explosion=null;
In the loadStageObject function, after the grenade object is created, we assign the
name of the callback function ( initializeExplosion ) to the explosionCallBack
property of the grenade object. It is invoked once its animation has finished. After
the explosion object is created, we invoke initExplosionTextures to load all the
textures shown previously.
function
loadStageObject(url,location,rotationX,rotationY,rotationZ){
...
else if(nameOfObject=="grenade"){
stageObject=new Grenade();
grenade=stageObject;
grenade.explosionCallBack=initializeExplosion;
}else if(nameOfObject=="explosion"){
stageObject=new Explosion();
explosion=stageObject;
initExplosionTextures();
}
...
}