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iOS Build a Game with Sprite Kit Artificial Intelligence and Sound Increasing Difficulty

Natalie Carlson
Natalie Carlson
3,727 Points
Posted by Natalie Carlson
Natalie Carlson
3,727 Points

Enemy Speed

If we change minSpeed depending on gameTime, shouldn't we also update THSpaceDogMinSpeed when we spawn the dog? We set minSpeed but then we never actually do anything with it. Or did I miss something?

Thanks! I love these videos!

1 Answer

Enara L. Otaegi
Enara L. Otaegi
13,107 Points
Enara L. Otaegi
Enara L. Otaegi
13,107 Points

You're right. But we can't update the constant THSpaceDogMinSpeed. What I did:

if (self.totalGameTime > 480) {
        // 480 / 60 = 8 minutes
        self.addEnemyTimeInterval = 0.5;
        self.minSpeed = THSpaceDogMinSpeed - 60;
        self.maxSpeed = THSpaceDogMaxSpeed - 60;
}

I created a maxSpeed variable because when calculating the random Speed I wanted it to increase evenly.

So in the random method we pass:

float dy = [THUtil randomWithMin:self.minSpeed max:self.maxSpeed];
Natalie Carlson
Natalie Carlson
3,727 Points
Natalie Carlson
Natalie Carlson
3,727 Points

Thanks for the recommendation with declaring a maxSpeed too. I actually changed the THSpaceDogMinSpeed to exclude the const property. I think I'll take your recommendation and return to the program, include the const for THSpaceDogMinSpeed, set self.minSpeed = THSpaceDogMinSpeed and then include self.minSpeed and self.maxSpeed as the variables for the random value for the velocity. This programmatically is better code.

Thanks for your time!