The gltfio API allows users to destroy ResourceLoader or FilamentAsset
even when various asynchronous work (e.g. uploading buffers to the GPU)
has not yet been completed. This was achieved in an error-prone manner
using manual reference counting and an internal management object called
AssetPool.
This PR refactors gltfio by wrapping cgltf_data in shared_ptr, which I
usually try to avoid. However in this case it provides the precisely the
functionality that is needed.
I tested this PR for memory leaks and crashes by hacking gltf_viewer
and monitoring memory usage in Activity Monitor.
This fixes#3383 and makes it easier to implement some missing features,
such as animation support for instanced assets.
This prepares for #3137 by moving the mesh cache and material instance
cache out of the loader (where they were transient anyway) and into the
actual asset. This paves the way for a `createInstance()` API.
This feature adds one new method to `FilamentAsset` and uses it in our
Kotlin, JavaScript, and C++ helpers:
utils::Entity popRenderable() noexcept;
This pops a ready renderable off an internal queue, or returns 0 if no
renderables have become ready. It provides a simple way for clients to
gradually add renderables to the scene as they become ready. Previously
clients could only get the entire list of entities, regardless of
whether they had Renderable components or complete textures.
To facilitate this feature, this PR adds a new internal-only class to
gltfio called `DependencyGraph`, which is a temporary object used for
bookkeeping during the asynchronous load.
`DependencyGraph` discovers ready-to-render entities by tracking the
textures that each entity depends on. This is a graph because
renderables connect to a set of material instances, which in turn
connect to a set of parameter names, which in turn connect to a set of
texture objects. These relationships are not easily inspectable using
the Filament API or ECS.
Some buffers (like animation data) do not contain any vertex data
but web-based clients still need to know about this.
This interface is much simpler than the bindings lists, and in fact
we might remove the binding lists in the future to simplify the API.
Fixes#1593.
This makes it easy to draw a transformed box around each renderable for
diagnostic purposes. The API is similar to Animator in that it is
exposed through FilamentAsset but is created lazily and is implementated
outside of FilamentAsset.
This is our new mobile-friendly and web-friendly library for loading
glTF assets. It is still a work in progress, but already capable of
loading many conformance models, including those with animation,
skinning, and a couple of extensions (nonlit and texture transforms).
Next week we will add a sample app demonstrating its usage.