WIP: feat(const_eval): impl. reflect

Author: ErichDonGubler

naga/Cargo.toml

@@ -90,6 +90,7 @@ termcolor = { version = "1.4.1" }
 # termcolor minimum version was wrong and was fixed in
 # https://github.com/brendanzab/codespan/commit/e99c867339a877731437e7ee6a903a3d03b5439e
 codespan-reporting = { version = "0.11.0" }
+half = { version = "2.4.1", default-features = false }
 hashbrown.workspace = true
 half = { workspace = true, features = ["arbitrary", "num-traits"] }
 rustc-hash.workspace = true

naga/src/proc/constant_evaluator.rs

@@ -1273,6 +1273,21 @@ impl<'a> ConstantEvaluator<'a> {
                 })
             }
 
+            // geometry
+            // crate::MathFunction::Reflect => {
+            //     let dot = |scalar: Scalar| match scalar {
+            //         Scalar::AbstractFloat([e1, e2]) => todo!(),
+            //         Scalar::F32([e1, e2]) => todo!(),
+            //         Scalar::AbstractInt([e1, e2]) => todo!(),
+            //         Scalar::U32([e1, e2]) => todo!(),
+            //         Scalar::I32([e1, e2]) => todo!(),
+            //     };
+            //     component_wise_float(self, span, [arg, arg1.unwrap()], |scalars| {
+            //         let dot = dot(scalars);
+            //         Ok([e1 - 2 * dot(e2, e1) * e2])
+            //     })
+            // }
+
             // computational
             crate::MathFunction::Sign => {
                 component_wise_signed!(self, span, [arg], |e| { Ok([e.signum()]) })