fix(🐛): rounding issues with getYForX (#375)

wcandillon · Oct 12, 2020 · bf93164 · bf93164
1 parent 602d176
commit bf93164
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Showing 4 changed files with 21 additions and 12 deletions.
diff --git a/src/Math.ts b/src/Math.ts
@@ -184,7 +184,8 @@ export const cubicBezierYForX = (
   a: Vector,
   b: Vector,
   c: Vector,
-  d: Vector
+  d: Vector,
+  precision = 2
 ) => {
   "worklet";
   const pa = -a.x + 3 * b.x - 3 * c.x + d.x;
@@ -193,7 +194,7 @@ export const cubicBezierYForX = (
   const pd = a.x - x;
   // eslint-disable-next-line prefer-destructuring
   const t = solveCubic(pa, pb, pc, pd)
-    .map((root) => round(root, 5))
+    .map((root) => round(root, precision))
     .filter((root) => root >= 0 && root <= 1)[0];
   return cubicBezier(t, a.y, b.y, c.y, d.y);
 };
diff --git a/src/Paths.ts b/src/Paths.ts
@@ -286,7 +286,7 @@ export const close = () => {
     // ~151
     getYForX(p1, 50)
  */
-export const getYForX = (path: Path, x: number) => {
+export const getYForX = (path: Path, x: number, precision = 2) => {
   "worklet";
   const p = path.filter((c) => {
     if (isCurve(c)) {
@@ -298,7 +298,7 @@ export const getYForX = (path: Path, x: number) => {
     return false;
   });
   if (p.length > 0 && isCurve(p[0])) {
-    return cubicBezierYForX(x, p[0].from, p[0].c1, p[0].c2, p[0].to);
+    return cubicBezierYForX(x, p[0].from, p[0].c1, p[0].c2, p[0].to, precision);
   }
   return 0;
 };