Bullet shells & Debris, A few pre-development questions

TRAVOLTRON

Hi guys,
I am considering using GS for a concept I have been tossing around. I would like bullet shells to fall to the ground and bounce when the character shoots, and remain on the ground for some time.I would also use this effect with the blood debris when an enemy is killed.
Would this use the particle engine? Are there limits for how many particles can be on screen at a time or will too many choke the game? I couldn't find any demos showing off the capacity of the engine.

This video of the game 'Liero' shows the bullet shell and blood particle effect I'm describing-

https://youtu.be/KE2XtQaMb5I

I hope this is possible.

Thanks for your help everyone

KevinCross

I've not used the particles in GameSalad yet but I don't see why the bouncing couldn't be done with game physics switched on. Making them disappear after a set time is as simple as adding a Timer Rule like this:

Timer: After 1 second
Destroy Actor

I would think it would be easier to use physics then particles but like I say I've not used particles yet. Not needed too

jamie_c

If you want your 'particles' to be interactive, ie. bounce off the floor and have physics you will need to create your own custom particles using actual actor and NOT USE the built in particle effects engine. The Particles Behavior creates particles that are images only and do not interact with the environment. I have a particle effect kit for sale on my site, I'm not suggesting you purchase it but if you watch the video promo, you'll see in the last 'sparks' particles I've used a combination of the Particles Behavior and custom particles created out of actors. The majority of the effect is 'regular' particles but the few that bounce off the floor are the custom actor particles.

So in short you'd be able to create what you need either with a combination of the particle behavior and your own custom particles or just through custom particles.

TRAVOLTRON

Ahh I see, I may not need to use the particle engine after all. So when the character shoots, a bullet shell actor will be spawned. Is there any limit to how many actors can be on screen at a time? There may be quite a few shells and bits of debris at once. Maybe a delayed timer on each actor would prevent too many from appearing.

Thanks for getting back to me!

TRAVOLTRON

I did find this useful post that (correct me if I'm wrong) could be used to create a giblet explosion that falls to the ground.

@Thunder_Child said:
I don't use the particles behavior. What I do is create an actor called debris.

I make my debris actor interpolate alpha to 0 in 1 second, move at random 1,359 degrees direction, destroy after 1.25 seconds, and I make the size of actor about 12x12.

My ship shoots a bullet (actor) at an enemy (actor). I set my bullet actor (When collide or overlap with "enemy", spawn actor "debris"). I spawn about 8 debris actors per collide.

So...when the bullet hits an enemy, it will spawn 8 debris actors in random directions for 1 second. Nice effect

KevinCross

Yeah that sounds about right and with gravity/physics turned on they should fall to the ground and bounce. Similar thing with the bullet shells, although you probably won't want a random direction applied to those, and you just spawn a bullet shell each time a bullet is shot.

As for the number of actors spawned at once I'm sure I've seen some tests on the forum where people have tried to push the limits. Can't remember what the findings were but you could probably find the information here on the forums. Or create some test projects yourself to see how many spawned actors it takes before you start seeing a strain on the performance.

jamie_c

Is there any limit to how many actors can be on screen at a time? There may be quite a few shells and bits of debris at once. Maybe a delayed timer on each actor would prevent too many from appearing.

@TRAVOLTRON, absolutely. Sounds like you found the thread from @Thunder_Child already that explains it.

To limit the number of shells you would create an Integer Attribute and increment it each time a shell is spawned, if you only wanted 10 shells to ever display at once do a check like this:

if Shells Attribute is < 10
Spawn a new shell actor

Then in each shell actor you could do something like this to fade it away and destroy it:

Interpolate Alpha from 1 to 0 Duration 1 second

If alpha = 0 destroy the actor

By checking the alpha value above you can destroy the actor as needed without needing a bunch of Timer Behaviors in all your shells.

Update: I've attached a little sample if you need it. Click the mouse button to spawn up to 10 shells at once.

TRAVOLTRON

Perfect! I'm liking what I'm hearing. Thank you @jamie_c & @KevinCross I'll move forward with my game.

Thunder_Child

@TRAVOLTRON you should also keep in mind not only the debris you are spawning but the number of bullets per second. I personally have found a bullet every .1sec plus the debris particles spawned upon a collision with enemy of around 8 that interpolate and destroy very quickly doesn't cause hardly any lag over a period of more than a few seconds. If this is happening continuously you may have to back off on something...usually the FX stuff not your game needed bullet spawning as that can change game play rather quickly.

Also of course if your talking about debris....and some reason using an image for that debris....there is no need to make that image you import to be some mammoth 1024x1024 image...keep it small.

TRAVOLTRON

Cheers @Thunder_Child I'll keep an eye on that. The game will be quite fast paced so I hope I don't run into any lag issues.