Fix fragment shader bug on empty curves

1 files changed, 4 insertions, 2 deletions

diff --git a/src/lerp.rs b/src/lerp.rs
index 222671f..1501d0f 100644
--- a/src/lerp.rs
+++ b/src/lerp.rs
@@ -4,6 +4,7 @@ use crate::poly::Poly;
 pub enum Lerp {
     Node(Box<Lerp>, Box<Lerp>),
     Leaf(Number, Number),
+    Just(Number)
 }
 
 impl Lerp {
@@ -13,8 +14,8 @@ impl Lerp {
 
     fn new_s(v: &[Number]) -> Box<Lerp> {
         match v.len() {
-            0 => Box::new(Lerp::Leaf(0.0, 0.0)),
-            1 => Box::new(Lerp::Leaf(v[0], v[0])),
+            0 => Box::new(Lerp::Just(0.0)),
+            1 => Box::new(Lerp::Just(v[0])),
             2 => Box::new(Lerp::Leaf(v[0], v[1])),
             _ => Box::new(Lerp::Node(
                 Lerp::new_s(&v[0..v.len() - 1]),
@@ -26,6 +27,7 @@ impl Lerp {
 
 pub fn lp(l: Box<Lerp>) -> Poly {
     match *l {
+        Lerp::Just(a) => Poly::new(vec![a]),
         Lerp::Leaf(a, b) => Poly::new(vec![a, b - a]),
         Lerp::Node(a, b) => {
             let a = lp(a);