We still use resgen for convience, but the archive is now passed in
from the client application.
This will allow us to shrink the gltfio Android library (stay tuned).
An ubershader archive is a bundle of filamat packages with some metadata
that conveys which glTF features each material supports.
This PR does three things:
1. Adds a new command line tool called `uberz` that consumes a list
of filamat files and metadata text files and produces a single
ubershader archive.
2. Adds a new library (also called `uberz`) that is used by `gltfio`
to read ubershader archives, and used by the above command line
tool to write ubershader archives.
3. Enhances `UbershaderLoader` so that it no longers uses a hardcoded
set of materials, and instead takes an ubershader archive.
Ubershader archives have a simple binary layout that can be memcpy'd
directly into a C struct. The metadata is specified using a text file
with key-value pairs. These two file formats have formal desriptions in
the README in `libs/uberz`.
In a subsequent PR, we will remove the `gltfio_resources` target and
change the signature of `createUbershaderLoader` so that it takes
an archive.
* gltfio: Clear texture caches before loading resources
* iOS gltf-viewer: add double-tap to reload model for debugging
* iOS samples: add instructions on ASan / UBSan debugging
- Ensure C++17 is used to compile sample projects
- Upgrade to the latest Xcodegen and re-generate projects
- Add a bundle ID disambiguator so users don't need create unique bundle Ids when opening sample projects
- Add a simple generate-samples.sh script
* Add multi-scene support to gltf_viewer.
To test this, I generated a multi-scene asset as follows.
```
gltf-transform merge Avocado/glTF/Avocado.gltf \
BarramundiFish/glTF/BarramundiFish.gltf \
~/Desktop/Merged.gltf
```
* Specify c++17 in pbxproj files.
This adds a new implementation of the TextureProvider interface called
Ktx2Provider.
Tested using the KTX2 variant of the StainedGlassLamp model in the
Khronos samples repo.
Tested on WebGL 2.0 (Chrome v100), Android (Pixel 6 Pro), and Desktop
(Metal, OpenGL, and Vulkan via MoltenVK).
This allows clients to provide their own asynchronous texture decoders
for various mime-typed images. This is a plug-in component for gltfio,
in some ways similar to MaterialProvider.
There are two motivations for this: to decouple gltfio from STB and
to make it easier to integrate support for BasisU textures.
This also has the side effect of simplifying ResourceLoader, since the
texture decoding jobs have been moved out.
As part of this work, I made the "stb" CMake target into a traditional
static library. Previously we had several files called `Image.cpp`
whose sole purpose was to enable STB_IMAGE_IMPLEMENTATION.
Changes:
- Remove the strange header-only variant of libs/image
- Rename KtxBundle => Ktx1Bundle
- Move image/KtxUtility => ktxreader/Ktx1Reader
- Add unit test for Ktx1Reader and test stub for KTX2.
Notes:
- Ktx1Bundle does not depend on Filament and is used by cmgen
and mipgen to generate KTX files.
- Ktx1Reader has a dependency on Filament and should therefore live in
a separate library, which it now does.