Add palette function for ordered ids

Given an id and a list of sorted ids, yields a color

src/components/plates/util.rs

@@ -40,6 +40,19 @@ impl ColorPalette {
         let mut r = SmallRng::seed_from_u64(t.as_u128() as u64);
         self.get(r.gen_range(0.0..1.0f64))
     }
+
+    pub fn get_ordered(&self, t: uuid::Uuid, ordered_uuids: &Vec<uuid::Uuid>)
+        -> [f64; 3] {
+        let index = ordered_uuids.iter().position(|&x| x == t).expect("uuid must be in list of uuids");
+        return self.get(Self::space_evenly(index))
+    }
+
+    fn space_evenly(x: usize) -> f64 {
+        let e: usize = (x.ilog2() + 1) as usize;
+        let d: usize = (2usize.pow(e as u32)) as usize;
+        let n: usize = (2*x + 1) % d;
+        return (n as f64) / (d as f64);
+    }
 }
 
 #[non_exhaustive]