basic tween structure

Cargo.lock

@@ -0,0 +1,7 @@
+# This file is automatically @generated by Cargo.
+# It is not intended for manual editing.
+version = 4
+
+[[package]]
+name = "rendo-tween"
+version = "0.1.0"

src/lib.rs

@@ -0,0 +1,15 @@
+pub struct Tween<T> {
+    tweeners: Vec<Tweener<T>>,
+}
+
+pub enum Tweener<T> {
+    TweenFunction {
+        function: fn(t: f32, min: T, max: T) -> T,
+    },
+    TweenInterval {
+        interval: f32,
+    },
+    TweenCallback {
+        callback: fn(),
+    },
+}