[Merged by Bors] - KTX2/DDS/.basis compressed texture support #3884

superdump · 2022-02-07T15:10:13Z

Objective

Support compressed textures including 'universal' formats (ETC1S, UASTC) and transcoding of them to
Support .dds, .ktx2, and .basis files

Solution

Fixes Compressed texture support #3608 Look there for more details.
Note that the functionality is all enabled through non-default features. If it is desirable to enable some by default, I can do that.
The basis-universal crate, used for .basis file support and for transcoding, is built on bindings against a C++ library. It's not feasible to rewrite in Rust in a short amount of time. There are no Rust alternatives of which I am aware and it's specialised code. In its current state it doesn't support the wasm target, but I don't know for sure. However, it is possible to build the upstream C++ library with emscripten, so there is perhaps a way to add support for web too with some shenanigans.
There's no support for transcoding from BasisLZ/ETC1S in KTX2 files as it was quite non-trivial to implement and didn't feel important given people could use .basis files for ETC1S.

crates/bevy_render/src/texture/dds.rs

crates/bevy_render/src/texture/basis.rs

crates/bevy_render/src/texture/dds.rs

crates/bevy_render/src/texture/ktx2.rs

superdump · 2022-02-08T21:57:39Z

crates/bevy_render/src/texture/ktx2.rs

+                    {
+                        return Err(TextureError::FormatRequiresTranscodingError(
+                            TranscodeFormat::Rgb8,
+                        ));


Maybe an error is a strange way to communicate this but...

crates/bevy_render/src/texture/ktx2.rs

crates/bevy_render/src/texture/mod.rs

superdump · 2022-02-15T15:41:26Z

I've looked this over some more and gone through to remove/address a bunch of FIXMEs I'd left. I changed my mind and now I'm thinking that it's better to just get this in rather than being overly careful. It's better that people start using it and we iterate rather than letting perfect be the enemy of good.

Cargo.toml

superdump · 2022-03-06T02:59:38Z

About the need to add GltfPlugin and ImagePlugin after the renderer initialisation: would the normal case still work if that's not done?

There are plans to make renderer initialisation async, which is needed at least for android and webgpu

Then I guess RenderDevice will not be available and this will panic? Maybe they should be changed back to .get_resource::<RenderDevice>().map_or_else(|| wgpu::Features::empty(), |render_device| render_device.features()) or similar but correct?

superdump · 2022-03-06T03:24:04Z

About the need to add GltfPlugin and ImagePlugin after the renderer initialisation: would the normal case still work if that's not done?
There are plans to make renderer initialisation async, which is needed at least for android and webgpu

Then I guess RenderDevice will not be available and this will panic? Maybe they should be changed back to .get_resource::<RenderDevice>().map_or_else(|| wgpu::Features::empty(), |render_device| render_device.features()) or similar but correct?

Although, this will basically mean that there will be no compressed texture support on Android and WebGPU and that isn't acceptable. So this is just something that needs to be solved. I tried to look into if the loader can be mutated after initialisation, but then I realised that that wouldn't work as it could allow attempts to load assets before enough information is available to do so. Some things have to wait until the renderer is initialised. How exactly we do that, I don't know.

mockersf · 2022-03-06T03:32:14Z

the async plugin story in Bevy is not great for now, it sounds like we will need to work on it to have compressed texture support everywhere

superdump · 2022-03-06T12:15:29Z

the async plugin story in Bevy is not great for now, it sounds like we will need to work on it to have compressed texture support everywhere

Yes, and it feels like it is outside the scope of this PR.

crates/bevy_render/src/texture/mod.rs

superdump · 2022-03-15T10:32:30Z

By the way, I didn't do the blanket matches so it was easy to see what formats there were in the library and which were supported and not, by looking at the code. I'm fine with it either way though.

cart · 2022-03-15T22:14:25Z

By the way, I didn't do the blanket matches so it was easy to see what formats there were in the library and which were supported and not, by looking at the code. I'm fine with it either way though.

I think I'd prefer to bias toward smaller code + eliminate redundancies. People that want to add new formats will know what they're looking for and can look at the enum definitions / docs to find out if its supported.

cart · 2022-03-15T22:15:17Z

(but thanks for the heads up. thats definitely a reasonable approach and I probably should have discussed it before making the change)

cart

This looks good to me. This supports like a million permutations of texture types, so I can't really test that it works. But this feels like a "let people yell at us if we did something wrong" sort of situation.

cart · 2022-03-15T22:26:29Z

bors r+

# Objective - Support compressed textures including 'universal' formats (ETC1S, UASTC) and transcoding of them to - Support `.dds`, `.ktx2`, and `.basis` files ## Solution - Fixes #3608 Look there for more details. - Note that the functionality is all enabled through non-default features. If it is desirable to enable some by default, I can do that. - The `basis-universal` crate, used for `.basis` file support and for transcoding, is built on bindings against a C++ library. It's not feasible to rewrite in Rust in a short amount of time. There are no Rust alternatives of which I am aware and it's specialised code. In its current state it doesn't support the wasm target, but I don't know for sure. However, it is possible to build the upstream C++ library with emscripten, so there is perhaps a way to add support for web too with some shenanigans. - There's no support for transcoding from BasisLZ/ETC1S in KTX2 files as it was quite non-trivial to implement and didn't feel important given people could use `.basis` files for ETC1S.

bors · 2022-03-15T23:00:43Z

Pull request successfully merged into main.

Build succeeded:

superdump · 2022-03-15T23:17:33Z

Woohoo!

# Objective - Support compressed textures including 'universal' formats (ETC1S, UASTC) and transcoding of them to - Support `.dds`, `.ktx2`, and `.basis` files ## Solution - Fixes bevyengine#3608 Look there for more details. - Note that the functionality is all enabled through non-default features. If it is desirable to enable some by default, I can do that. - The `basis-universal` crate, used for `.basis` file support and for transcoding, is built on bindings against a C++ library. It's not feasible to rewrite in Rust in a short amount of time. There are no Rust alternatives of which I am aware and it's specialised code. In its current state it doesn't support the wasm target, but I don't know for sure. However, it is possible to build the upstream C++ library with emscripten, so there is perhaps a way to add support for web too with some shenanigans. - There's no support for transcoding from BasisLZ/ETC1S in KTX2 files as it was quite non-trivial to implement and didn't feel important given people could use `.basis` files for ETC1S.

github-actions bot added the S-Needs-Triage This issue needs to be labelled label Feb 7, 2022

superdump mentioned this pull request Feb 7, 2022

Compressed texture support #3608

Closed

2 tasks

superdump added A-Assets Load files from disk to use for things like images, models, and sounds A-Rendering Drawing game state to the screen C-Feature A new feature, making something new possible and removed S-Needs-Triage This issue needs to be labelled labels Feb 7, 2022

superdump force-pushed the compressed-textures branch from 7f01cff to fa574dc Compare February 7, 2022 15:17

superdump self-assigned this Feb 7, 2022