Add comments to help explain Graphene concepts

node-graph/gcore/src/structural.rs

@@ -2,6 +2,25 @@ use core::marker::PhantomData;
 
 use crate::{Node, NodeMut};
 
+// This is how we can generically define composition of two nodes.
+// This is done generically as shown: <https://files.keavon.com/-/SurprisedGaseousAnhinga/capture.png>
+// A concrete example: <https://files.keavon.com/-/ExcitableGoldRay/capture.png>
+// And showing the direction of data flow: <https://files.keavon.com/-/SoreShimmeringElephantseal/capture.png>
+///                       ┌────────────────┐
+///                 T     │                │     U
+///           ───────────►│  Compose Node  ├───────────►
+///                       │                │
+///                       └────┬───────────┤
+///  ┌──────────┐              │           │
+///  │          │    T -> V    │           │
+///  │  First   ├─────────────►│           │
+///  │          │              │           │
+///  └──────────┘              │           │
+///  ┌──────────┐              │           │
+///  │          │    V -> U    │           │
+///  │  Second  ├─────────────►│           │
+///  │          │              └───────────┘
+///  └──────────┘
 #[derive(Clone, Copy)]
 pub struct ComposeNode<First, Second, I> {
 	first: First,

node-graph/gcore/src/types.rs

@@ -102,12 +102,18 @@ impl PartialEq for TypeDescriptor {
 	}
 }
 
+/// Graph runtime type information used for type inference.
 #[derive(Clone, PartialEq, Eq, Hash, specta::Type)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 pub enum Type {
+	/// A wrapper for some type variable used within the inference system. Resolved at inference time and replaced with a concrete type.
 	Generic(Cow<'static, str>),
+	/// A wrapper around the Rust type id for any concrete Rust type. Allows us to do equality comparisons, like checking if a String == a String.
 	Concrete(TypeDescriptor),
+	/// Runtime type information for a function. Given some input, gives some output.
+	/// See the example and explanation in the `ComposeNode` implementation within the node registry for more info.
 	Fn(Box<Type>, Box<Type>),
+	/// Not used at the moment.
 	Future(Box<Type>),
 }