Game Development Reference
In-Depth Information
The
initialize
function takes the
modelMatrix
of the grenade as a parameter. The
objective is simple: the explosion has to occur at the same location and orientation
of the grenade in its last frame. Hence, we clone the received model matrix and
simply assign it to the model matrix of the
Explosion
object. We also initialize the
textureIndex
class variable to the first element of the
texture
array.
Explosion.prototype.initialize=function(modelMatrix) {
this.modelMatrix=mat4.clone(modelMatrix);
this.counter=0;
this.textureIndex=this.textureIndices[0];
this.visible=true;
this.frames=0;
}
The
update
function increments the
counter
and assigns the index of the next
texture in the
textureIndices
array. Once the animation has finished, we toggle
the visibility of the texture.
Explosion.prototype.update=function() {
if(this.counter<this.textureIndices.length){
this.textureIndex=this.textureIndices[this.counter];
this.counter-++;
}
else{
this.visible=false;
this.counter=0;
}
}
We also need to do a small change in the
Grenade.js
file from the
primitive/game
folder of the code bundle.
We need to add a callback function (
explosionCallBack
) to the
Grenade
class so
that we can pass the model matrix of the grenade in the last frame and initialize
our explosion.
Grenade= inherit(StageObject, function (){
...
this.explosionCallBack=null;
});
