dotCooCoo · Nov 13, 2026 · Nov 14, 2026 · Nov 14, 2026 · Nov 14, 2026 · Nov 14, 2026
diff --git a/ATTRIBUTION.md b/ATTRIBUTION.md
@@ -21,6 +21,7 @@ author, source and license. Library code and original assets are under the repos
 | `crates/text/assets/hyphen/en-us.pat` | DesignCraft contributors, trained from the Moby Hyphenator II list | `crates/text/examples/hyphgen.rs` | CC0-1.0 |
 | Patterns embedded through `hypher` (optional `craft-text` language features) | hyph-utf8 authors, per language | [tex-hyphen](https://github.com/hyphenation/tex-hyphen), as packaged in [hypher](https://github.com/typst/hypher/tree/main/patterns) | Per file header: LPPL, MIT, BSD-3-Clause, Unlicense or a permit-any-use notice (or a choice including one); Slovak (`hyph-sk.tex`, embedded whenever `hypher/slovak` is on: feature `slovak-gpl`, or another dependency through feature unification) is GPL-2.0-or-later; Spanish (`hyph-es.tex` 5.0, Javier Bezos, CervanTeX) is MIT |
 | Word-break dictionaries and LSTM models embedded through `icu_segmenter_data` (optional `craft-text` features `thai`, `lao`, `khmer`, `burmese`) | Unicode, Inc. and ICU4X contributors | [ICU4X](https://github.com/unicode-org/icu4x) | Unicode-3.0 |
+| MikkTSpace tangent generation compiled in through `mikktspace` (`craft-mesh-ops`) | Benjamin Wasty, David Harvey-Macaulay and Layl Bongers; translated from the C original by Morten S. Mikkelsen | [mikktspace 0.3.0](https://crates.io/crates/mikktspace/0.3.0), [gltf-rs/mikktspace](https://github.com/gltf-rs/mikktspace) | MIT OR Apache-2.0 (the package's `license` field); its `src/generated.rs` also carries the C original's 2011 notice, reproduced in [`crates/mesh-ops/ATTRIBUTION.md`](crates/mesh-ops/ATTRIBUTION.md) |
 | `crates/ui/tests/fonts/NotoSansArabic-test.ttf` (subset to the test strings, default weight set to 100, width axis dropped) | The Noto Project Authors | [google/fonts@7085eb8 `ofl/notosansarabic`](https://github.com/google/fonts/tree/7085eb89a950e85db5b166b7a58d414544b4140c/ofl/notosansarabic), via craft-fonts | OFL-1.1 (`licenses/ui-test-fonts/OFL-NotoSansArabic.txt`) |
 | `crates/ui/tests/fonts/NotoSansCJKsc-test.otf` (subset to the test strings) | The Noto Project Authors (Adobe, Google) | [notofonts/noto-cjk@f8d1575 `Sans/OTF/SimplifiedChinese`](https://github.com/notofonts/noto-cjk/tree/f8d157532fbfaeda587e826d4cd5b21a49186f7c/Sans/OTF/SimplifiedChinese), via craft-fonts | OFL-1.1 (`licenses/ui-test-fonts/OFL-NotoSansCJK.txt`) |
 | `crates/ui/tests/fonts/NotoSansArabic-screens.ttf` (instance at weight 400 and width 100, subset to the screen test strings) | The Noto Project Authors | [google/fonts@7085eb8 `ofl/notosansarabic`](https://github.com/google/fonts/tree/7085eb89a950e85db5b166b7a58d414544b4140c/ofl/notosansarabic), via craft-fonts | OFL-1.1 (`licenses/ui-test-fonts/OFL-NotoSansArabic.txt`) |

diff --git a/Cargo.lock b/Cargo.lock
diff --git a/Cargo.toml b/Cargo.toml
@@ -70,6 +70,7 @@ craft-gcode = { path = "crates/gcode" }
 craft-gif = { path = "crates/gif" }
 craft-hdr = { path = "crates/hdr" }
 craft-mesh = { path = "crates/mesh" }
+craft-mesh-ops = { path = "crates/mesh-ops" }
 craft-html = { path = "crates/html" }
 craft-heif = { path = "crates/heif" }
 craft-fig = { path = "crates/fig" }

diff --git a/NOTICE b/NOTICE
@@ -63,6 +63,10 @@ craft-proof Language data, embedded at build time from craft-i18n's language-dat
   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
   OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   POSSIBILITY OF SUCH DAMAGE.
+mikktspace 0.3.0 (https://crates.io/crates/mikktspace/0.3.0), a dependency of crates/mesh-ops,
+  is MIT OR Apache-2.0. Its src/generated.rs, a translation of Morten S. Mikkelsen's C
+  MikkTSpace, carries that original's 2011 zlib-style notice, which must not be removed or
+  altered; crates/mesh-ops/ATTRIBUTION.md reproduces it in full.
 crates/text/assets/hyphen/en-us.pat: CC0-1.0, trained from en-us.dic by DesignCraft's trainer.
 Hyphenation patterns for other languages, embedded through the hypher crate only when the
   matching craft-text feature is enabled (none are by default). They come from hyph-utf8,
@@ -215,6 +219,20 @@ The colour management module in crates/cms is extracted from:
   Licensed MIT OR Apache-2.0. Its generated ICC profile is dedicated to the public domain
   (CC0-1.0); see ATTRIBUTION.md.
 
+The mesh operations in crates/mesh-ops are moved from:
+- TextureCraft, crates/geom (src/mesh.rs, bvh.rs, primitives.rs, gbuffer.rs, unwrap.rs,
+  camera.rs and their tests), revision 386630ee85cb22679295b24013575d1aecb39ad2.
+  https://github.com/storytold/texturecraft
+  Copyright (c) 2026 ArtCraft Team and the TextureCraft contributors.
+- MaterialCraft, crates/geom/src/mesh.rs (subdivision and its test), revision
+  3133062968b8a1566eda12a357cb06062db16687.
+  https://github.com/storytold/materialcraft
+  Copyright (c) 2026 ArtCraft Team and the MaterialCraft contributors.
+  The index check before tangent generation and its two tests are from TextureCraft pull
+  request #386 by simonhull, revision faa4548a6f34bb61d43f56b3500edb73dd71981b
+  (https://github.com/storytold/texturecraft/pull/386).
+  All licensed MIT OR Apache-2.0.
+
 Optional PDF writer
 
 Krilla 0.8.2 (https://github.com/LaurenzV/krilla), MIT OR Apache-2.0.

diff --git a/README.md b/README.md
@@ -269,6 +269,10 @@ See the [release notes](CHANGELOG.md) for included functionality and known limit
   glTF 2.0 / GLB and 3MF, one feature each. Readers are bounded by `Limits`, never open a file themselves
   glTF 2.0 / GLB and FBX, one feature each. Readers are bounded by `Limits`, never open a file themselves
   and never panic. Carved from EffectCraft, SolidCraft, TextureCraft and MaterialCraft.
+- [`craft-mesh-ops`](crates/mesh-ops/README.md): operations on triangle meshes: smooth normals,
+  MikkTSpace tangents, welding, UV unwrapping, a UV-space G-buffer, primitives with UVs and a
+  BVH for ray casts (feature `bvh`), with slice functions checked against `Limits`. From
+  TextureCraft and MaterialCraft.
 - [`craft-midi`](crates/midi/README.md): Standard MIDI Files: a bounded reader for formats 0, 1 and
   2 and a format-1 writer, over a neutral model of notes and channel events in ticks at 960 per
   quarter note. From SoundCraft.

diff --git a/crates/mesh-ops/ATTRIBUTION.md b/crates/mesh-ops/ATTRIBUTION.md
@@ -0,0 +1,32 @@
+# Attribution
+
+`craft-mesh-ops` generates tangents with the `mikktspace` crate.
+
+| Package | Authors | Source | License |
+|---|---|---|---|
+| `mikktspace` 0.3.0 | Benjamin Wasty, David Harvey-Macaulay, Layl Bongers | [crates.io](https://crates.io/crates/mikktspace/0.3.0), [gltf-rs/mikktspace](https://github.com/gltf-rs/mikktspace) | MIT OR Apache-2.0 (the package's `license` field) |
+
+The package's `src/generated.rs` is a translation of Morten S. Mikkelsen's C implementation of
+the MikkTSpace algorithm and carries that implementation's notice, reproduced here unchanged:
+
+```text
+Copyright (C) 2011 by Morten S. Mikkelsen
+
+This software is provided 'as-is', without any express or implied
+warranty.  In no event will the authors be held liable for any damages
+arising from the use of this software.
+
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
+
+1. The origin of this software must not be misrepresented; you must not
+claim that you wrote the original software. If you use this software
+in a product, an acknowledgment in the product documentation would be
+appreciated but is not required.
+
+2. Altered source versions must be plainly marked as such, and must not be
+misrepresented as being the original software.
+
+3. This notice may not be removed or altered from any source distribution.
+```
diff --git a/crates/mesh-ops/Cargo.toml b/crates/mesh-ops/Cargo.toml
@@ -0,0 +1,26 @@
+[package]
+name = "craft-mesh-ops"
+description = "Triangle mesh operations: smooth normals, MikkTSpace tangents, welding, UV unwrapping, a UV-space G-buffer, primitives with UVs and a BVH, bounded on hostile input"
+version.workspace = true
+edition.workspace = true
+license.workspace = true
+rust-version.workspace = true
+repository.workspace = true
+
+[lints]
+workspace = true
+
+[features]
+default = []
+bvh = []
+parallel = ["dep:rayon"]
+serde = ["dep:serde", "glam/serde"]
+
+[dependencies]
+glam = "0.30"
+# MIT OR Apache-2.0; its src/generated.rs also carries the zlib-style notice of the C original,
+# reproduced in ATTRIBUTION.md.
+mikktspace = { version = "0.3", default-features = false, features = ["glam"] }
+rayon = { workspace = true, optional = true }
+serde = { workspace = true, optional = true }
+thiserror = { workspace = true }