When creating a KTX file (e.g. with mipgen), you can of course choose
whether or not you want to use an sRGB format.
At load time, your app has an expectation about whether a particular
texture has an sRGB format. e.g. the glTF convention is that albedo
textures should be sRGB, while roughness textures are linear.
Before this commit, our KTX loader would look at the app's expectation,
then silently re-interpret the bits in the glTF texture in order to
match this expectation. This seems very wrong.
Instead, if the expectated format does not match the format in the KTX
file, we now print a warning.
Fixes#2422, which will also be obsoleted by our upcoming KTX2 support.
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.
