Game Development Reference
In-Depth Information
How to do it
Continuing with the same Xcode project, now we will create our solution kit for this
chapter that is, Chapter 4.
The following are the steps to add the spaceship's thrust in our game:
1. Open the
FSMyScene
class and add a method called
addSpaceShipThrust
.
To get a particle file, first we need the file's path to pick it from the bundle. The
method to find the path will require the name of the particle file and its type.
NSString *emitterPath = [[NSBundle mainBundle]
pathForResource:@"FireParticle" ofType:@"sks"];
2. After this, we can instantiate a new object of
SKEmitterNode
with the file path
that is,
emitterPath
used in preceding code. This is accomplished by using
NSKeyedUnarchiver
, which will return an object of
SKEMitterNode
for a
path that is provided.
SKEmitterNode *emitterNode = [NSKeyedUnarchiver
unarchiveObjectWithFile:emitterPath];
3. Once the object of emitter is created, specify its position which has to be given ac-
cording to the center of the spaceship as it's its thrust.
emitterNode.particlePosition =
CGPointMake(-self.spaceShipSprite.frame.size.width/
2,0);
4. Lastly, after all the configuration is done, just add the
emitterNode
object to
SpaceShipSprite
.
[self.spaceShipSprite addChild:emitterNode];
5. Call the
addSpaceShipThrust
method in the
init
method just after the
ad-
dSpaceShip
method.
6. The preceding
SKEmitterNode
was fully created using the
SpriteKit Particle
file. But we can tweak the properties of
SKEmitterNode
in the code itself.
7. As we want to increase the speed of the thrust after adding the emitter node, simil-
arly, for this, we can edit the speed property of the emitter node object.
