gltfio can now ask the material provider plugin which `Material` would
be used for a given set of requirements. Prior to this change, gltfio
could only create a new `MaterialInstance`.
This method is necessary to support an upcoming gltfio feature.
This change was motivated by some internal work at Google and has the
benefit of simplifying the gltfio API and implementation. There are 2
major API changes:
(1) Consolidate separate loader entry points for GLB and GLTF.
The distinction between GLB and GLTF can be made from the file content
alone, because GLB has a 4-byte magic string in its header. There is no
need for separate entry points. Clients do not (and should not) need
to check the file name extension.
(2) Remove the distinction between "instanced" and "non-instanced"
glTF assets.
In the new scheme, all assets have at least 1 instance.
Broadly speaking, in gltfio an "asset" is a collection of Filament
objects like textures and vertex buffers, while an "instance" is a
collection of entities and components (e.g. the transform hierarchy).
This API change makes life easier for clients because they no longer
need to decide a priori if they will ever need to add instances.
This change also moves some public-facing methods from FilamentAsset to
FilamentInstance:
- getSkinCount, getSkinNameAt
- getJointCountAt, getJointsAt
- attachSkin, detachSkin
This is a gltfio API change (!)
Jave clients now need to call destroy on MaterialProvider.
Previously, the Java AssetLoader took over ownership of a native
material provider upon construction, but this was neither documented
nor consistent with the C++ layer. (This is historical; in the past we
did not expose MaterialProvider to Java.)
One motivation for this (aside from API consistency) is that users may
wish to preserve the material cache from one run to another.
Fixes#5132.
This adds some significant JNI glue in order to make the Java API for
gltfio materials much more consistent with C++, and create feature
parity between the two languages.
The motivation is to allow Java clients to provide their own
ubershader-based solution or filamat-based solution.
- The `MaterialProvider` Java class is now an interface.
- The `UbershaderLoader` Java class is now a concrete implementation.
- Users can now write their own provider class using Java / Kotlin.
To streamline the amount of JNI work that occurs at run time, the
MaterialProvider Java interface uses ints in a couple spots instead
of enums. This sacrafices some readability for Java clients who wish
to write their own provider, but makes the JNI much simpler.
This replaces #3975.
We currently use static linking and will continue to do so. This means
that libfilament-jni is a subset of of libgltfio-jni, and libgltfio-jni
will become a subset of the upcoming libutils-jni.
This is a simple layer cake, but requires adding some CMake logic to the
gltfio-android CMakeLists, similar to what we already did for the
filament-android CMakeLists. This prevents an obscure CMake error about
duplicated build artifacts.
Also, previously we required clients to call AssetLoader#init(), this
is now renamed to Gltfio#init(), which is more consistent with
Filament#init().
For now this uses gltfio in the ubershader configuration in order
to avoid the filamat dependency. Note that we have not yet done a size
analysis of the `gltfio_core` library.
New Kotlin-based sample app is forthcoming.
