From 1558fd9519301a7679b1c0ea5d9d3da3d8d2b004 Mon Sep 17 00:00:00 2001
From: Felix Roos <roos@entrecode.de>
Date: Sat, 12 Mar 2022 20:38:06 +0100
Subject: [PATCH] fix draw return + optional querying

---
 repl/src/draw.mjs | 20 ++++++++++++--------
 1 file changed, 12 insertions(+), 8 deletions(-)

diff --git a/repl/src/draw.mjs b/repl/src/draw.mjs
index aa8a6d2a..b8abca91 100644
--- a/repl/src/draw.mjs
+++ b/repl/src/draw.mjs
@@ -14,25 +14,29 @@ export const getDrawContext = (id = 'test-canvas') => {
   return canvas.getContext('2d');
 };
 
-Pattern.prototype.draw = function (callback, duration) {
+Pattern.prototype.draw = function (callback, queryDuration) {
   if (window.strudelAnimation) {
     cancelAnimationFrame(window.strudelAnimation);
   }
   const ctx = getDrawContext();
-  let cycle, events;
+  let cycle,
+    events = [];
   const animate = (time) => {
     const t = Tone.getTransport().seconds;
-    const currentCycle = Math.floor(t / duration);
-    if (cycle !== currentCycle) {
-      cycle = currentCycle;
-      const begin = currentCycle * duration;
-      const end = (currentCycle + 2) * duration;
-      events = this.add(0).query(new State(new TimeSpan(begin, end)));
+    if (queryDuration) {
+      const currentCycle = Math.floor(t / queryDuration);
+      if (cycle !== currentCycle) {
+        cycle = currentCycle;
+        const begin = currentCycle * queryDuration;
+        const end = (currentCycle + 2) * queryDuration;
+        events = this.add(0).query(new State(new TimeSpan(begin, end)));
+      }
     }
     callback(ctx, events, t, time);
     window.strudelAnimation = requestAnimationFrame(animate);
   };
   requestAnimationFrame(animate);
+  return this;
 };
 
 export const cleanup = () => {