New tools for long-form compositions: setLoop() and cyclecounter()

packages/codemirror/widget.mjs

@@ -140,3 +140,8 @@ registerWidget('_spectrum', (id, options = {}, pat) => {
   const ctx = getCanvasWidget(id, options).getContext('2d');
   return pat.spectrum({ ...options, ctx, id });
 });
+
+registerWidget('_cyclecounter', (id, options = {}, pat) => {
+  const ctx = getCanvasWidget(id, options).getContext('2d');
+  return pat.cyclecounter({ ...options, ctx, id });
+});

packages/core/cyclist.mjs

@@ -23,6 +23,8 @@ export class Cyclist {
     this.beforeStart = beforeStart;
     this.cps = 0.5;
     this.num_ticks_since_cps_change = 0;
+    this.loopStart = 0;
+    this.loopLength = 0;
     this.lastTick = 0; // absolute time when last tick (clock callback) happened
     this.lastBegin = 0; // query begin of last tick
     this.lastEnd = 0; // query end of last tick
@@ -48,6 +50,10 @@ export class Cyclist {
           this.lastBegin = begin;
           const end = this.num_cycles_at_cps_change + num_cycles_since_cps_change;
           this.lastEnd = end;
+          if (this.loopLength > 0 && this.lastEnd >= this.loopStart + this.loopLength) {
+            this.lastEnd = this.loopStart + (this.lastEnd % 1);
+            this.num_ticks_since_cps_change = 0;
+          }
           this.lastTick = phase;
 
           if (phase < t) {
@@ -116,7 +122,7 @@ export class Cyclist {
   stop() {
     logger('[cyclist] stop');
     this.clock.stop();
-    this.lastEnd = 0;
+    this.lastEnd = this.loopStart;
     this.setStarted(false);
   }
   async setPattern(pat, autostart = false) {
@@ -132,6 +138,19 @@ export class Cyclist {
     this.cps = cps;
     this.num_ticks_since_cps_change = 0;
   }
+  setLoop(start = 0, length = 0) {
+    if (start >= 0 && length >= 0) {
+      start = Math.floor(start);
+      length = Math.floor(length);
+
+      if (start != this.loopStart || length != this.loopLength) {
+        this.loopStart = Math.floor(start);
+        this.loopLength = Math.floor(length);
+        this.lastEnd = this.loopStart + (this.lastEnd % 1);
+        this.num_ticks_since_cps_change = 0;
+      }
+    }
+  }
   log(begin, end, haps) {
     const onsets = haps.filter((h) => h.hasOnset());
     console.log(`${begin.toFixed(4)} - ${end.toFixed(4)} ${Array(onsets.length).fill('I').join('')}`);

packages/core/repl.mjs

@@ -86,6 +86,7 @@ export function repl({
   const toggle = () => scheduler.toggle();
   const setCps = (cps) => scheduler.setCps(cps);
   const setCpm = (cpm) => scheduler.setCps(cpm / 60);
+  const setLoop = (start, length) => scheduler.setLoop(start, length);
 
   // TODO - not documented as jsdoc examples as the test framework doesn't simulate enough context for `each` and `all`..
 
@@ -167,6 +168,8 @@ export function repl({
       setcps: setCps,
       setCpm,
       setcpm: setCpm,
+      setLoop,
+      setloop: setLoop,
     });
   };
 

packages/draw/cyclecounter.mjs

@@ -0,0 +1,16 @@
+import { Pattern } from '@strudel/core';
+
+Pattern.prototype.cyclecounter = function (options = {}) {
+  return this.onPaint((ctx, time, haps, drawTime) => {
+    ctx.clearRect(0, 0, ctx.canvas.width, ctx.canvas.height);
+
+    ctx.font = options.font || '2em monospace';
+    ctx.fillStyle = options.color || 'red';
+    ctx.textBaseline = 'bottom';
+    ctx.textAlign = 'right';
+
+    const div = options.div || 1;
+
+    ctx.fillText('Cycle' + (div > 1 ? '/' + div : '') + ' ' + ((time / div) >> 0), ctx.canvas.width, ctx.canvas.height);
+  });
+};

packages/draw/index.mjs

@@ -4,3 +4,4 @@ export * from './draw.mjs';
 export * from './pianoroll.mjs';
 export * from './spiral.mjs';
 export * from './pitchwheel.mjs';
+export * from './cyclecounter.mjs';