Roll our own matrix code & separate math into new crate (#27)

* Implement matrix subset locally

* Use multiply_add in matrix math

* Update MSRV lockfile

* Refactor xy_to_xyz a bit

* Create yuvxyb-math crate

* ci: Run clippy on subcrate

* Update MSRV lockfile

.github/workflows/crate.yml

@@ -35,3 +35,11 @@ jobs:
         run: cargo build
       - name: Run tests
         run: cargo test
+
+  lint-math:
+    runs-on: ubuntu-latest
+
+    steps:
+      - uses: actions/checkout@v4
+      - name: Lint
+        run: cargo clippy --manifest-path yuvxyb-math/Cargo.toml

.gitignore

@@ -1,3 +1,7 @@
 /target
 /Cargo.lock
 yuvxyb-dump
+
+# subcrate-specific
+yuvxyb-math/target
+yuvxyb-math/Cargo.lock

Cargo.toml

@@ -9,27 +9,22 @@ homepage = "https://github.com/rust-av/yuvxyb"
 repository = "https://github.com/rust-av/yuvxyb"
 exclude = ["test_data", "yuvxyb-dump"]
 
-# When changing MSRV: Also update README and .github/workflows/crate.yml
+# When changing MSRV: Also update README, yuvxyb-matrix and .github/workflows/crate.yml
 rust-version = "1.64.0"
 
 [features]
 default = ["fastmath"]
-fastmath = []
+fastmath = ["yuvxyb-math/fastmath"]
 
 [dependencies]
+yuvxyb-math = { version = "0.1.0", path = "yuvxyb-math" }
 av-data = "0.4.2"
 log = "0.4.17"
 num-traits = "0.2.15"
 paste = "1.0.9"
 thiserror = "1.0.40"
 v_frame = "0.3.8"
 
-[dependencies.nalgebra]
-version = "0.32.2"
-# The default features include macros that we don't need
-default-features = false
-features = ["std"]
-
 [dev-dependencies]
 criterion = { version = "0.5", default-features = false }
 image = { version = "0.25", default-features = false, features = ["png"] }

src/lib.rs

@@ -32,7 +32,6 @@
 #![warn(clippy::use_debug)]
 #![warn(clippy::verbose_file_reads)]
 
-mod math;
 mod rgb_xyb;
 mod yuv_rgb;
 

src/rgb_xyb.rs

@@ -1,6 +1,6 @@
 #![allow(clippy::many_single_char_names)]
 
-use crate::math::cbrtf;
+use yuvxyb_math::cbrtf;
 
 const K_M02: f32 = 0.078f32;
 const K_M00: f32 = 0.30f32;