Implements MovieClip.getBounds, and also reorganized the
DisplayObject AABB methods:
* `self_bounds` calculates the inherent untransfomed bounds of
the object without children. All `DisplayObject`s must implement
this method. For example, `Bitmap` returns the size of bitmap.
Composite objects like `MovieClip` return a null AABB because they
are made up of only children.
* `bounds` calculates the untransformed bounds including children.
* `local_bounds` calculates the bounds relative to the object's
parent.
* `world_bounds` calculates the bounds in global stage space.
* `bounds_with_transform` calculates a tight AABB for the object
with a given transform, and is used to implement the above.
Initial support for loading multiple movies:
* `loadMovie`/`loadMovieNum`
* `loadVariables`/`loadVariablesNum`
* XML loading
Desktop currently only loads from the local file system.
Try to keep style more consistent by using functions for all MC
methods. Previous was a mix of closures and functions (we're still
a little bad with this elsewhere)
This is caused by the fact that `avm.root_object` references the *current* stack frame, not the one we are about to introduce. Ergo, we need to pull the base clip of the *new* stack frame and find it's root.
This particular behavior only crops up in situations where there can be multiple root objects, at least until we implement `_lockroot`.
`_root` is calculated dynamically based on the clip the currently executing function was called in.
Other things that used `context.root` have been changed to either update all layers or just update layer 0, which is the former `context.root`.
Interestingly enough, very little actually has to be done inside the async process for XML. The async process basically just fetches data and fires an event handler when it's done. Everything else is handled via a system builtin, `XML.onData`.
This implementation just returns the size of the current loaded movie. The test is also deliberately written to be loose on timings so that it likely won't see a partially loaded movie. (I don't want it to be a test of load events, so I just wait a few frames, rather than the correct way of waiting for `onLoadComplete`.)
Until we support streaming file loads, we can't faithfully support these properties. Still, it's better to have them, just in case.
This is technically better, but it may make more sense to trigger `ClipEvent::Load` at the start of the next frame instead. Furthermore, I don't know if other forms of load events should trigger on the next frame (or end of the current one) like this.
Loads in Flash Player, like all web technologies, are asynchronous tasks of some kind (probably a separate thread). They appear to operate on some kind of a delay. If I `trace` each frame out, like in the previous version of `mcl_loadclip`, you get a series of events that look like this:
1. Parent frame 1
2. Parent frame 2
3. Event: onLoadStart
4. Event: onLoadProgress
5. Event: onLoadComplete
6. Parent frame 3
7. Event: onLoadInit
If I run that version of the test on Ruffle, everything happens after frame 1. This is an artifact of how we're testing asynchronous behavior in Ruffle. In order to guarantee test determinism, we have a dummy implementation of `fetch` that does a blocking load, and we poll all futures every frame of execution. This means that there is a very specific order of execution with these tests, which is good for testing, but probably isn't 100% accurate.
Flash Player appears to delay all loads by at least one frame, even loads that are coming from disk which should load immediately. I don't know if this is intentional or not, so I don't want to implement a load delay just for the sake of making tests pass. Ergo, I'm loosening the tests to just test the ability to load and unload movies, and fire events from a loader.
Specifically:
1. `mcl_loadclip` no longer traces out frames of the parent timeline
2. `unloadmovie` et. all use a target movie that doesn't fail the test until 10 frames have passed.
If someone can find a movie network that breaks with fast loading, then I'll consider implementing explicit frame delays for async tasks. Otherwise, this is how we're testing this.
This also adjusts `MovieClip.unloadMovie` to do just that, instead of removing the clip from the display list. We also have to unload clips when loading new movies into them, since `unloadMovie` desugars to loading `""` as the URL.
Interestingly, this constitutes an implementation of `AsBroadcaster`. It appears Macromedia decided to implement event handling on `MovieClipLoader` in a very similar fashion to `AsBroadcaster`, down to invoking `broadcastMessage` and searching a `_listeners` property for listeners.
*De*implement the free function versions of the above, as well as their `Num` variants, since they don't actually exist as callables. Instead, the ActionScript compiler treats them as preprocessor functions that represent various forms of `ActionGetURL`/`ActionGetURL2`.
This function is part of `Avm1`, rather than a hypothetical `LayerManager`, because we're going to need to eventually construct layers differently for AVM2.
Mike Welsh