bevy/crates/bevy_mikktspace/LICENSE-MIT

Copyright (c) 2017 The mikktspace Library Developers

Permission is hereby granted, free of charge, to any
person obtaining a copy of this software and associated
documentation files (the "Software"), to deal in the
Software without restriction, including without
limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of
the Software, and to permit persons to whom the Software
is furnished to do so, subject to the following
conditions:

The above copyright notice and this permission notice
shall be included in all copies or substantial portions
of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF
ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED
TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT
SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR
IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.
Generate vertex tangents using mikktspace (#3872) # Objective Models can be produced that do not have vertex tangents but do have normal map textures. The tangents can be generated. There is a way that the vertex tangents can be generated to be exactly invertible to avoid introducing error when recreating the normals in the fragment shader. ## Solution - After attempts to get https://github.com/gltf-rs/mikktspace to integrate simple glam changes and version bumps, and releases of that crate taking weeks / not being made (no offense intended to the authors/maintainers, bevy just has its own timelines and needs to take care of) it was decided to fork that repository. The following steps were taken: - mikktspace was forked to https://github.com/bevyengine/mikktspace in order to preserve the repository's history in case the original is ever taken down - The README in that repo was edited to add a note stating from where the repository was forked and explaining why - The repo was locked for changes as its only purpose is historical - The repo was integrated into the bevy repo using `git subtree add --prefix crates/bevy_mikktspace git@github.com:bevyengine/mikktspace.git master` - In `bevy_mikktspace`: - The travis configuration was removed - `cargo fmt` was run - The `Cargo.toml` was conformed to bevy's (just adding bevy to the keywords, changing the homepage and repository, changing the version to 0.7.0-dev - importantly the license is exactly the same) - Remove the features, remove `nalgebra` entirely, only use `glam`, suppress clippy. - This was necessary because our CI runs clippy with `--all-features` and the `nalgebra` and `glam` features are mutually exclusive, plus I don't want to modify this highly numerically-sensitive code just to appease clippy and diverge even more from upstream. - Rebase https://github.com/bevyengine/bevy/pull/1795 - @jakobhellermann said it was fine to copy and paste but it ended up being almost exactly the same with just a couple of adjustments when validating correctness so I decided to actually rebase it and then build on top of it. - Use the exact same fragment shader code to ensure correct normal mapping. - Tested with both https://github.com/KhronosGroup/glTF-Sample-Models/tree/master/2.0/NormalTangentMirrorTest which has vertex tangents and https://github.com/KhronosGroup/glTF-Sample-Models/tree/master/2.0/NormalTangentTest which requires vertex tangent generation Co-authored-by: alteous <alteous@outlook.com> 2022-05-31 22:53:54 +00:00			`Copyright (c) 2017 The mikktspace Library Developers`

			`Permission is hereby granted, free of charge, to any`
			`person obtaining a copy of this software and associated`
			`documentation files (the "Software"), to deal in the`
			`Software without restriction, including without`
			`limitation the rights to use, copy, modify, merge,`
			`publish, distribute, sublicense, and/or sell copies of`
			`the Software, and to permit persons to whom the Software`
			`is furnished to do so, subject to the following`
			`conditions:`

			`The above copyright notice and this permission notice`
			`shall be included in all copies or substantial portions`
			`of the Software.`

			`THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF`
			`ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED`
			`TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A`
			`PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT`
			`SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY`
			`CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION`
			`OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR`
			`IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER`
			`DEALINGS IN THE SOFTWARE.`