Add PartialEq for GeometryPixel (#401)

Used in unit tests further down the stack.

Author: mkeeter

CHANGELOG.md

@@ -10,6 +10,7 @@
       now all generate `BytecodeOp::Sub` (using the reserved register as needed
       for immediates).
     - This also removes the `enum RegOpDiscriminants` from `fidget_core`
+- Add `PartialEq` for `GeometryPixel`
 
 # 0.4.2
 - Change `depth` member in `GeometryPixel` from `u32` to `f32` ([#381](https://github.com/mkeeter/fidget/pull/381))

fidget-raster/src/lib.rs

@@ -434,7 +434,9 @@ impl<P, S: ImageSizeLike> std::ops::IndexMut<(usize, usize)> for Image<P, S> {
 ///
 /// This type can be passed directly in a buffer to the GPU.
 #[repr(C)]
-#[derive(Debug, Default, Copy, Clone, IntoBytes, FromBytes, Immutable)]
+#[derive(
+    Debug, Default, Copy, Clone, IntoBytes, FromBytes, Immutable, PartialEq,
+)]
 pub struct GeometryPixel {
     /// Z position of this pixel, in voxel units
     ///