fix: restore ComponentMap and ColorComponentMap in prelude for v0.8 compat

CHANGELOG.md

@@ -1,4 +1,59 @@
 
+# 0.8.92
+
+## Display and Hex formatting fixes
+
+* Hex formatting no longer wraps output in the type name. `format!("{:x}", RGB::new(255u8, 0, 0))` now returns `#ff0000` instead of `RGB { #ff0000 }`.
+* BGR/BGRA hex formatting now outputs in logical RGB order. Previously, `BGR { b: 0, g: 0, r: 255 }` (a red pixel) would format as `#0000FF`, which looks like blue. It now correctly outputs `#FF0000`.
+* Hex formatting for `u16` components now pads each component to 4 hex digits, matching the component width. Previously it used a fixed 2-digit minimum, making it impossible to tell where one component ended and the next began (e.g. `#1A2B010F` is now `#1A2B0001000F`).
+* BGRA `Display` now prints values in field order to match the label: `bgra(b,g,r,a)`. Previously it printed `bgra(r,g,b,a)`, which was inconsistent with the format name.
+
+## Trait changes
+
+* The `prelude` now additionally exports `Pixel`, `HetPixel`, `GainAlpha`, `HasAlpha`, and `ArrayLike`. The previous `ComponentMap` and `ColorComponentMap` exports are preserved for backwards compatibility.
+
+* `map_colors()` is now on the `HetPixel` trait (included in the prelude) instead of `ColorComponentMap`. Code using method syntax (`.map_colors()`) is unaffected. Code using trait-qualified calls needs updating:
+
+  ```rust
+  // Before — no longer compiles
+  use rgb::prelude::*;
+  let p = RGBA::new(1u8, 2, 3, 255);
+  let mapped: RGBA<u16, u8> = ColorComponentMap::map_colors(&p, |c| c as u16);
+
+  // After
+  use rgb::prelude::*;
+  let p = RGBA::new(1u8, 2, 3, 255);
+  let mapped: RGBA<u16, u8> = HetPixel::map_colors(&p, |c| c as u16);
+  ```
+
+* The `unstable-experimental` feature flag has been removed. Code gated on `#[cfg(feature = "unstable-experimental")]` is now dead code. `Gray` remains `Gray_v08` and `GrayAlpha` remains `GrayAlpha_v08`; the new `Gray_v09` and `GrayA` types are available separately.
+
+## Migrating to the new Gray types
+
+`Gray_v09` and `GrayA` use named fields (`.v`, `.a`) instead of tuple fields (`.0`, `.1`), and support the new `Pixel`/`HetPixel` traits. To opt into them now, alias at the import site:
+
+```rust
+use rgb::Gray_v09 as Gray;
+use rgb::GrayA;
+```
+
+Key differences from the legacy types:
+
+| | `Gray` (v08) | `Gray_v09` |
+|---|---|---|
+| Construction | `Gray(100)` | `Gray { v: 100 }` or `Gray::new(100)` |
+| Field access | `.0` | `.v` |
+| Deref | `*g` yields `T` | No deref |
+| `.value()` / `.value_mut()` | Yes | Yes |
+
+| | `GrayAlpha` (v08) | `GrayA` |
+|---|---|---|
+| Construction | `GrayAlpha(100, 255)` | `GrayA { v: 100, a: 255 }` or `GrayA::new(100, 255)` |
+| Field access | `.0`, `.1` | `.v`, `.a` |
+| `.value()` | Yes | Yes |
+
+Both old and new types support `::new()`, `.value()`, and `.value_mut()`, so code using those methods works with either type unchanged.
+
 # 0.8.41
 
 * Renamed `.alpha(new_val)` method to `.with_alpha(new_val)`.

src/lib.rs

@@ -96,6 +96,9 @@ pub mod prelude {
     pub use crate::HasAlpha;
     pub use crate::HetPixel;
     pub use crate::Pixel;
+    // Back-compat: these were in the v0.8 prelude
+    pub use crate::ColorComponentMap;
+    pub use crate::ComponentMap;
 }
 
 /// `TryFrom` errors