How can I create a random spawn point for enemies?

[WhiteSoul]

Hello.

 

I'm almost finishing my first game, but I'm stuck with the enemies issue...

I want that the enemies comes from the upper part of the screen at random intervals but I can't do it.

 

I was looking for tutorials but I don't know how to do it.

I think that I need to create a group for the enemies and I did that already.

 

Thank you so much in advance.

 

Regards, Daniel.

[lewster32]

This example has a random enemy spawner which you could analyse and adapt to your game: http://gamemechanicexplorer.com/#homingmissiles-5

[WhiteSoul]

Thank you so much.

 

That website seems so interesting to learn about games but it seems a bit difficult to me, hehe. Anyways I will try to implement it.

[lewster32]

Stick with it - the examples on that site are brilliantly written and well commented. If you get stuck let us know and we'll see what we can do

[WhiteSoul]

Oh, that's so nice, thank you.

 

I will also take a look at Phaser's GitHub documentation page, so maybe in that way I can understand the game states.

[bryanbibat]

Here's another tutorial with a section for spawning random enemies from the top: https://leanpub.com/html5shootemupinanafternoon/read#leanpub-auto-enemy-sprite-group

[Heppell08]

If you have a group of enemies and want them to spawn from the top of the screen randomly then in your group creation and spawn you can set the Y to above world height and set the X to game.world.randomX;

[WhiteSoul]

Thank you so much for the help!

That book seems awesome and very useful.

And about that tip, I didn't knew that you could do that.

 

Let's see if finally I can finish my game hahaha.

[WhiteSoul]

Yes, it worked! Finally!

I'm so happy my first game is almost done. ^^

 

But now I want to make the enemy group disappear when they hit the player, I was using "enemies.kill()" but that only kills the enemy that touched the player, the other ones keep appearing.

I want to use that so it only appears on the screen "Game Over".

 

Thank you guys again for all the interest.

[Heppell08]

You'd need to set up a few arguments like.

if(player.exists === false)

{ ... Game over etc here }

But it totally depends on how you have the logic laid out really. Just check for the death of player or use a physics collode/overlap to do the callbacks if the player dies on contact with the enemy.

[WhiteSoul]

Yes, I'm using a colliding system, so the thing that I want to achieve is that when one enemy of the group touches the player the whole group disappear.

 

I already have the text "Game Over" placed but the problem is that the enemies keep appearing.

[Dumtard]

As Heppell said it depends on how you set up the logic for your enemy spawning. Basically you have to have some logic so that you can stop the spawn, if you are using a timer, stop the timer, if you are calling a function that spawns enemies every frame in your update method, stop calling that when its time for game over, etc.

An easier more general answer would be to set up a GameOver State and switch states to that to display your game over, and a button for restarting, etc.

[WhiteSoul]

Oh, ok, I didn't think it in that way... I will try it, thank you.

[WhiteSoul]

I've been thinking how to do that, but I have no clue... ^^;

 

This is the code that spawns the enemies that I have inside the update function:

if (game.nextEnemyAt < game.time.now && enemies.countDead() > 0) {					game.nextEnemyAt = game.time.now + game.enemyDelay;	var enemy = enemies.getFirstExists(false);	enemy.reset(game.rnd.integerInRange(20, 280), 0);        enemy.body.velocity.y = game.rnd.integerInRange(190, 280);	enemy.play("movement");				}

The problem is that I don't know how to stop that "if".

[Dumtard]

Add another check to the if statement that ensures it is not in the game over state so that if its game over it will not enter that statement.
 

var gameover = false;if (collision) {  gameover = true;}if (game.nextEnemyAt < game.time.now &&    enemies.countDead() > 0 &&    !gameover) {				  game.nextEnemyAt = game.time.now + game.enemyDelay;  var enemy = enemies.getFirstExists(false);  enemy.reset(game.rnd.integerInRange(20, 280), 0);  enemy.body.velocity.y = game.rnd.integerInRange(190, 280);  enemy.play("movement");				}

[WhiteSoul]

Oh, nice!

 

Thank you so much, let's see how can implement that because I was testing with it and the spawn didn't worked at all, I mean even without collision.

But I'm so close.

[Dumtard]

I don't know how exact you were following my code, but make sure var gameover = false is not in the update loop, initialize it only once.

 

You can also do as Heppell said earlier and check if the player still exists after being removed from collision.

if (game.nextEnemyAt < game.time.now &&    enemies.countDead() > 0 &&    player.exists) {				  game.nextEnemyAt = game.time.now + game.enemyDelay;  var enemy = enemies.getFirstExists(false);  enemy.reset(game.rnd.integerInRange(20, 280), 0);  enemy.body.velocity.y = game.rnd.integerInRange(190, 280);  enemy.play("movement");				}

[WhiteSoul]

Thank you for all the efforts.

Anyways I had the variable "gameover" out of the update loop with the other variables.

 

I will try that, I don't know why I didn't tried it before... ^^;

[WhiteSoul]

Yes, it works!!

Thank you guys for helping me a lot, without the help this game would be only a few ideas in my mind.

 

I only need one more step, let's see if I can do it alone. ^^

[WhiteSoul]

Oh, one last thing on this topic, do you guys mind if I post the game here with a CC license?

I'm mentioning this just in case there's a policy about that in these forums and because you guys helped me a lot so I feel like I'm on a group.

It's my first one, so I don't know exactly what to do...

[Dumtard]

There are several places you can post it,

http://www.html5gamedevs.com/forum/8-game-showcase/

http://www.html5gamedevs.com/topic/1975-game-list-of-phaser-games/

http://pgl.ilinov.eu/

[WhiteSoul]

Thank you so much for the links Dumtard, they will be very useful.

[lewster32]

By all means! Post it on the Game Showcase forum

[WhiteSoul]

Nice, thank you.

I was thinking doing that because I have an open topic, so I can place it there.