From dca8b46abffeb056b3c17a6c26f66835f01aff60 Mon Sep 17 00:00:00 2001
From: alex <alex@slab.org>
Date: Sat, 16 Apr 2022 11:40:47 +0100
Subject: [PATCH] add `degrade`/`degradeBy`

---
 packages/core/signal.mjs | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/packages/core/signal.mjs b/packages/core/signal.mjs
index a2f0e4e4..a6868937 100644
--- a/packages/core/signal.mjs
+++ b/packages/core/signal.mjs
@@ -88,3 +88,17 @@ export const perlinWith = (pat) => {
 };
 
 export const perlin = perlinWith(time);
+
+Pattern.prototype._degradeByWith = function (withPat, x) {
+  return this.fmap((a) => (_) => a).appLeft(withPat._filterValues((v) => v > x));
+};
+
+Pattern.prototype._degradeBy = function (x) {
+  return this._degradeByWith(rand, x);
+};
+
+Pattern.prototype._degrade = function () {
+  return this._degradeBy(0.5);
+};
+
+Pattern.prototype.patternified.push('degradeBy', 'degrade');