Implement basic variation support

enkou-shaders/src/chaos_game.rs

@@ -13,6 +13,7 @@
 //! This algorithm is also known as the ["chaos game"](https://en.wikipedia.org/wiki/Chaos_game),
 //! and it forms the basic system for producing images.
 use crate::transform::Transform;
+use crate::variation::Variation;
 use glam::{Vec2, vec2};
 use rand::distr::{Distribution, StandardUniform};
 use rand::{Rng, RngExt};
@@ -37,6 +38,7 @@ pub fn step_chaos_game<R: Rng>(
     rng: &mut R,
     transforms: &[Transform],
     weights: &[f32],
+    variations: &[Variation],
 ) -> (Vec2, u32) {
     let mut choice_weight = rng.sample::<f32, _>(StandardUniform);
     let mut transform_index: u32 = 0;
@@ -51,7 +53,7 @@ pub fn step_chaos_game<R: Rng>(
     }
 
     (
-        transforms[transform_index as usize].transform_point(point),
+        transforms[transform_index as usize].transform_point(rng, variations, point),
         transform_index,
     )
 }
@@ -65,17 +67,24 @@ pub struct ChaosGame<'a, R: Rng> {
     rng: &'a mut R,
     transforms: &'a [Transform],
     weights: &'a [f32],
+    variations: &'a [Variation],
 }
 
 impl<'a, R: Rng> ChaosGame<'a, R> {
     /// Create a new chaos game iterator
-    pub fn new(rng: &'a mut R, transforms: &'a [Transform], weights: &'a [f32]) -> Self {
+    pub fn new(
+        rng: &'a mut R,
+        transforms: &'a [Transform],
+        weights: &'a [f32],
+        variations: &'a [Variation],
+    ) -> Self {
         let current_point = vec2(rng.sample(BiUnit), rng.sample(BiUnit));
         ChaosGame {
             current_point,
             rng,
             transforms,
             weights,
+            variations,
         }
     }
 }
@@ -84,8 +93,13 @@ impl<'a, R: Rng> Iterator for ChaosGame<'a, R> {
     type Item = Vec2;
 
     fn next(&mut self) -> Option<Self::Item> {
-        let (next_point, _) =
-            step_chaos_game(self.current_point, self.rng, self.transforms, self.weights);
+        let (next_point, _) = step_chaos_game(
+            self.current_point,
+            self.rng,
+            self.transforms,
+            self.weights,
+            self.variations,
+        );
         self.current_point = next_point;
 
         Some(next_point)