Allow the immediate use of async images, once loaded

[T1mL3arn]

When I want to use async assets

<assets path="assets" embed="false" preload="false"/>

openfl.Assets.loadBitmapData(asset_id, true).onComplete(bd ->
{
	trace('image is loaded');
	FlxAssets.getBitmapData(asset_id);
});

I get this

image is loaded
ERROR: IMAGE asset "asset.png" exists, but only asynchronously'

because Flixel doesn't use cache when it gets bmd from openfl assets for some reason, I believe it is a bug.

--- update

example is valid for html5

[Geokureli]

This seems like a good change, I'd like to poke around the history and verify that there's no valid reason for this arg to be false in the first place (it's an optional arg which makes it was intentional for some reason) , but it seems like it's a good change.

The only issue is that this is gonna conflict with this PR: #2982, and this change may affect how I approach that other PR, so it just needs some consideration

[T1mL3arn]

there's no valid reason for this arg to be false

At least on openfl's side it is true by default.

[Geokureli]

I have one theory as to why it's false, I fear that if it's true it will return the same bitmap instance on each call rather than fetching a new copy. This means that editing one bitmap will effect all other sprites using the same path.

this is just a guess, but it's something I would like checked before merging this

[T1mL3arn]

This means that editing one bitmap will effect all other sprites using the same path.

Yes, it works that way.

[Geokureli]

I'm unable to reproduce this issue due to the following reasons:
the preload attribute does not actually affect asset tags in Project.xml

<assets path="assets" embed="false" preload="false"/>

it can only be used in library tags, which forces you to use the lib name in asset_id like so: "libName:assets/psth/to/image.png", and then if I try openfl.Assets.loadBitmapData(asset_id, true).onComplete(bd->{}); it returns an error 'could not find a library named "libName"'.
but if I use libraries in my project.cml and do: openfl.Assets.loadLibrary(asset_id).onComplete(bd->{}); then I'm able to load images in that library via FlxAssets.getBitmapData(asset_id) after it completes, despite useCache being false

[T1mL3arn]

I updated the original post - example is valid for html5. On sys targets assets are treat as local files and get re-read from filesystem when they are not cached (at least how I understand it from Lime sources).

[Geokureli]

it turns out the part i was missing was embed="false", preload does in fact do nothing in asset tags and I was able to reproduce the issue with both: <assets path="assets" embed="false" preload="false"/> and <assets path="assets" embed="false" preload="true"/>

[Geokureli]

This means that editing one bitmap will effect all other sprites using the same path.

Yes, it works that way.

So this doesn't seem to be the case, in the following example:

import flixel.FlxSprite;

class AsyncImageTestState extends flixel.FlxState
{
    inline static var PATH = "async-assets/images/haxe.png";
    
    override function create()
    {
        super.create();
        
        openfl.Assets.loadBitmapData(PATH, true).onComplete(
            function drawSprites(_)
            {
                for (i in 0...3)
                {
                    final sprite = new FlxSprite(10 + 110 * i, 10);
                    sprite.loadGraphic(PATH, false, 0, 0, true);
                    add(sprite);
                }
                // edit the first sprite, see if all change
                final bitmap = (cast members[0]:FlxSprite).graphic.bitmap;
                bitmap.fillRect(bitmap.rect, 0xFFff0000);
            }
        );
    }   
}

only the first sprite is modified, meaning unique is honored despite the use of caching. so this should be good