Manual Sprite Liftetime Management

Arcade Help
1

So i’ve recently decided to get back into Makecode for a little bit after spending a couple of months learning C++ Gamedev, and one of the things I’ve been finding hard to adjust to is not being able the manage the lifetimes of my sprites. I can use the sprites.destroyAllSpritesOfKind function but I feel as though its limiting to need to make a SpriteKind that is forced to be destroyed. I’ve tried storing an array of sprites but that causes a null access exception. Is there a alternative solution?

2

@Alex can you share the code that’s giving you the exception?

3 
let SpriteArr : Array<Sprite>

SpriteArr.push(sprites.create(SpriteTex.White))

Uncaught Dereferencing null/undefined value.
at (main.ts:1:1)

4

@Alex you need to assign that variable:

let spriteArray: Array<Sprite> = []
spriteArray.push(sprites.create(SpriteTex.White))
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5

Hi, @Alex !

Also keep in mind that, depending on what specifically you’re trying to do, there may be built-in tools that can help you.

MakeCode is event-driven, so some aspects of sprite lifetime could be handled in, say, the sprite overlap event handlers.

There also is a sprite flag called auto-destroy. If a sprite with auto-destroy leaves the screen, then the sprite is automatically released without having to manage it explicitly.

let projectile: Sprite = sprites.create(img`.`, SpriteKind.Projectile)
projectile.setFlag(SpriteFlag.AutoDestroy, true)
projectile.setVelocity(25, 25)

Of course, there’s nothing wrong with managing sprite lifecycle yourself! Just know that there may be other tools available to help you.

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