Sprite Kit - Add random Sprite Nodes to the scene with Switch Case - ios

Question

I have the following code to create random objects and add them to the scene. At the end the method is repeated after a random delay.
-(void)createObjects {
// Create random start point
float randomStartPoint = arc4random_uniform(4) * 64 + 32;
CGPoint startPoint = CGPointMake(self.size.width + 50, randomStartPoint);
// Create random object and add to scene
switch (arc4random_uniform(2)) {
case 0:
{
SKSpriteNode *crate = [SKSpriteNode spriteNodeWithImageNamed: #"crate"];
crate.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:crate.frame.size];
crate.physicsBody.dynamic = YES;
crate.physicsBody.affectedByGravity = NO;
crate.physicsBody.categoryBitMask = objectCategory;
crate.physicsBody.collisionBitMask = 0;
crate.physicsBody.contactTestBitMask = playerCategory;
crate.position = startPoint;
crate.name = #"object";
crate.zPosition = 20;
[self addChild:crate];
break;
}
case 1:
{
SKSpriteNode *cactus = [SKSpriteNode spriteNodeWithImageNamed: #"cactus"];
cactus.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:cactus.frame.size];
cactus.physicsBody.dynamic = YES;
cactus.physicsBody.affectedByGravity = NO;
cactus.physicsBody.categoryBitMask = objectCategory;
cactus.physicsBody.collisionBitMask = 0;
cactus.physicsBody.contactTestBitMask = playerCategory;
cactus.position = startPoint;
cactus.name = #"object";
cactus.zPosition = 20;
[self addChild:cactus];
break;
}
default:
break;
}
// After adding child, call same method at random delay
float randomNum = arc4random_uniform(4) * 0.4 + 0.25;
[self performSelector:#selector(createObjects) withObject:nil afterDelay:randomNum];
}
In reality I have many more cases and a lot of the same code is repeated, since every Sprite Node has the same settings. Is there a way to create a sprite node once, and in every case set a different image for the node, and add it to the scene?

Answer 1

You can create SKTexture in switch case and then simply create node with that texture.
Like this:
-(void)createObjects {
// Create random start point
float randomStartPoint = arc4random_uniform(4) * 64 + 32;
CGPoint startPoint = CGPointMake(self.size.width + 50, randomStartPoint);
// Create random object and add to scene
SKTexture* objectTexture;
switch (arc4random_uniform(2)) {
case 0:
objectTexture = [SKTexture textureWithImageNamed:#"crate"];
break;
case 1:
objectTexture = [SKTexture textureWithImageNamed:#"cactus"];
break;
default:
break;
}
SKSpriteNode *object = [SKSpriteNode spriteNodeWithTexture:objectTexture];
object.physicsBody = [SKPhysicsBody bodyWithRectangleOfSize:crate.frame.size];
object.physicsBody.dynamic = YES;
object.physicsBody.affectedByGravity = NO;
object.physicsBody.categoryBitMask = objectCategory;
object.physicsBody.collisionBitMask = 0;
object.physicsBody.contactTestBitMask = playerCategory;
object.position = startPoint;
object.name = #"object";
object.zPosition = 20;
[self addChild: object];
}
Another way would be to create object before switch case and then simply create texture and set it in switch case using setTexture: