Sprite Kit - Denoting a Hit Streak in a Game

Question

I've built a game with SpaceCat as the basis. I built a simple streak multiplier into the game using the method below.

- (void) didBeginContact:(SKPhysicsContact *)contact {
    SKPhysicsBody *firstBody, *secondBody;

    if (contact.bodyA.categoryBitMask < contact.bodyB.categoryBitMask ) {
        firstBody = contact.bodyA;
        secondBody = contact.bodyB;
    } else {
        firstBody = contact.bodyB;
        secondBody = contact.bodyA;
    }    
    if ( firstBody.categoryBitMask == THCollisionCategoryEnemy &&
         secondBody.categoryBitMask == THCollisionCategoryProjectile ) {
        NSLog(@"BAM!");

        THSpaceDogNode *spaceDog = (THSpaceDogNode *)firstBody.node;
        THProjectileNode *projectile = (THProjectileNode*)secondBody.node;

        // increase the counter
        _streakCount++;
        // add points considering the streak
        if (_streakCount >= 5) {
            [self addPoints:THPointsPerHit * 2];
        }
        if (_streakCount >= 10) {
            [self addPoints:THPointsPerHit * 3];
        }
        if (_streakCount >= 15) {
            [self addPoints:THPointsPerHit * 5];
        }
        if (_streakCount >= 20) {
            [self addPoints:THPointsPerHit * 10];
        }

        else {
            [self addPoints:THPointsPerHit];

        }

This code works great and the score is multiplying exactly how I want it to.

Now I'm trying to add a SKSpriteNode image that will pop up to show the user if they have a streak.

I was able to get the image to pop up by adding this code.

       if (_streakCount == 5) {
            SKSpriteNode *streakFive= [SKSpriteNode spriteNodeWithImageNamed:@"StreakFiveimg"];
            [streakFive setPosition:CGPointMake(self.size.width / 1.0366, self.size.height/1.46)];
             [self addChild:streakFive];

This works but I need to be able to make the image go away once their streak is broken. I tried adding some code to the "else" section that resets the point multiplier but that wasn't working for me. The score multiplier resets perfectly, but the streak image stays up on the screen.

If it's too complicated to make the images appear and disappear maybe it would be simpler to add a counter that displays the current streak and then resets to zero when the streak is broken. I'm not sure how to go about that either though.

I'm still learning and I would definitely appreciate any help that anyone is willing to offer!

Answer 1 · 2014-11-02T22:29:57Z

November 2, 2014 10:29pm

I think your looking for something like:

// Your code from above modified
SKSpriteNode *streakFive= [SKSpriteNode spriteNodeWithImageNamed:@"StreakFiveimg"];
if (_streakCount == 5) {
            streakFive.name = @"streakImage";
            [streakFive setPosition:CGPointMake(self.size.width / 1.0366, self.size.height/1.46)];
             [self addChild:streakFive];

SKNode *n = [self childNodeWithName: @"n"];
if (_streakCount == 0 && n) {
           [streakFive removeFromParent];
}

This will check if your steak count variable is back to zero and that your streakeFive variable is instantiated!

Hope this helps :)

Answer 2 · 2014-11-02T23:27:37Z

November 2, 2014 11:27pm

Thanks Ryan, Should that go in with the other if statements or somewhere else? When I put it in where I had it before, it's breaking everything.

Answer 3 · 2014-11-04T19:27:15Z

November 4, 2014 7:27pm

I figured it out. I was missing a bracket haha. Thanks!

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james baxter

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Sprite Kit - Denoting a Hit Streak in a Game

3 Answers

Ryan Ackermann

Ryan Ackermann

james baxter

james baxter

james baxter

james baxter

Ryan Ackermann

Ryan Ackermann