docs: expand trait and type documentation with examples

1 files changed, 28 insertions, 3 deletions

diff --git a/mingling_core/src/asset/renderer.rs b/mingling_core/src/asset/renderer.rs
index 732f9b7..f6dcbd0 100644
--- a/mingling_core/src/asset/renderer.rs
+++ b/mingling_core/src/asset/renderer.rs
@@ -1,10 +1,35 @@
 use crate::RenderResult;
 
-/// Takes over a type (`Self::Previous`) and converts it to a [`RenderResult`](./struct.RenderResult.html)
+/// Rendering logic for Mingling programs
+///
+/// Add a rendering type for registered types in the Mingling program. When they are routed to `to_render()`, this renderer will be invoked to render them into the result output.
+///
+/// # Manual impl
+///
+/// Generally speaking, it is recommended to use the [`#[renderer]`](https://docs.rs/mingling/latest/mingling/macros/attr.renderer.html) macro instead.
+/// If you need to implement this manually, please refer to the following example:
+///
+/// ```
+/// # use mingling_core::Renderer;
+/// # use mingling_core::RenderResult;
+/// # struct MyRenderer;
+/// # struct StateMyType;
+///
+/// impl Renderer for MyRenderer {
+///     type Previous = StateMyType;
+///
+///     fn render(prev: Self::Previous) -> RenderResult {
+///         // The specific rendering logic
+///         # return mingling_core::RenderResult::default();
+///     }
+/// }
+/// ```
 pub trait Renderer {
-    /// The previous type in the chain
+    /// The previous type handled by the renderer, used to convert it into a render result
     type Previous;
 
-    /// Process the previous value and write the result into the provided [`RenderResult`](./struct.RenderResult.html)
+    /// The rendering logic, which converts the `Previous` type into the corresponding [`RenderResult`] output
+    ///
+    /// When a program is routed to the type registered for this renderer, this method will be called to convert and render the previous type into the final result.
     fn render(p: Self::Previous) -> RenderResult;
 }