Implement bytemuck behind a feature (#775)

Cargo.lock

@@ -243,6 +243,20 @@ name = "bytemuck"
 version = "1.7.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "72957246c41db82b8ef88a5486143830adeb8227ef9837740bdec67724cf2c5b"
+dependencies = [
+ "bytemuck_derive",
+]
+
+[[package]]
+name = "bytemuck_derive"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e215f8c2f9f79cb53c8335e687ffd07d5bfcb6fe5fc80723762d0be46e7cc54"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "syn",
+]
 
 [[package]]
 name = "byteorder"
@@ -928,6 +942,7 @@ checksum = "e78d4f1cc4ae33bbfc157ed5d5a5ef3bc29227303d595861deb238fcec4e9457"
 name = "emath"
 version = "0.14.0"
 dependencies = [
+ "bytemuck",
  "mint",
  "serde",
 ]
@@ -973,6 +988,7 @@ dependencies = [
  "ab_glyph",
  "ahash",
  "atomic_refcell",
+ "bytemuck",
  "cint",
  "emath",
  "nohash-hasher",