Merge pull request #335 from tidalcycles/animate

animate mvp

packages/core/animate.mjs

@@ -0,0 +1,59 @@
+import { controls, Pattern, getDrawContext, silence, scheduler } from './index.mjs';
+const { createParams } = controls;
+
+let clearColor = '#20001010';
+let currentSmear = 0.5;
+export let syncAnimationWithScheduler = true;
+
+Pattern.prototype.animate = function (callback) {
+  window.frame && cancelAnimationFrame(window.frame);
+  const ctx = getDrawContext();
+  const { clientWidth: ww, clientHeight: wh } = ctx.canvas;
+  const render = (t) => {
+    let frame;
+    if (syncAnimationWithScheduler) {
+      t = scheduler.now();
+      frame = this.queryArc(t, t);
+    } else {
+      t = Math.round(t);
+      frame = this.slow(1000).queryArc(t, t);
+    }
+    ctx.fillStyle = clearColor;
+    ctx.fillRect(0, 0, ww, wh);
+    frame.forEach((f) => {
+      let { x, y, w, h, s, r, a = 0, fill = 'darkseagreen', smear } = f.value;
+      if (smear && smear !== currentSmear) {
+        currentSmear = smear;
+        let smearPart = Number((1 - smear) * 100).toFixed(0);
+        smearPart = smearPart.length === 1 ? `0${smearPart}` : smearPart;
+        clearColor = `#200010${smearPart}`;
+      }
+      w *= ww;
+      h *= wh;
+      if (r !== undefined && a !== undefined) {
+        const radians = a * 2 * Math.PI;
+        const [cx, cy] = [(ww - w) / 2, (wh - h) / 2];
+        x = cx + Math.cos(radians) * r * cx;
+        y = cy + Math.sin(radians) * r * cy;
+      } else {
+        x *= ww - w;
+        y *= wh - h;
+      }
+      const val = { ...f.value, x, y, w, h };
+      ctx.fillStyle = fill;
+      if (s === 'rect') {
+        ctx.fillRect(x, y, w, h);
+      } else if (s === 'ellipse') {
+        ctx.beginPath();
+        ctx.ellipse(x + w / 2, y + h / 2, w / 2, h / 2, 0, 0, 2 * Math.PI);
+        ctx.fill();
+      }
+      callback && callback(ctx, val, f);
+    });
+    window.frame = requestAnimationFrame(render);
+  };
+  window.frame = requestAnimationFrame(render);
+  return silence;
+};
+
+export const { x, y, w, h, a, r, fill, smear } = createParams('x', 'y', 'w', 'h', 'a', 'r', 'fill', 'smear');

packages/core/index.mjs

@@ -21,6 +21,7 @@ export * from './repl.mjs';
 export * from './logger.mjs';
 export * from './time.mjs';
 export * from './draw.mjs';
+export * from './animate.mjs';
 export * from './pianoroll.mjs';
 export * from './ui.mjs';
 export { default as drawLine } from './drawLine.mjs';

packages/core/repl.mjs

@@ -3,6 +3,10 @@ import { evaluate as _evaluate } from './evaluate.mjs';
 import { logger } from './logger.mjs';
 import { setTime } from './time.mjs';
 
+export let scheduler; // expose scheduler to global scope
+// this is not optimal as it will only work for one repl at a time
+// TODO: use pattern.context to expose scheduler
+
 export function repl({
   interval,
   defaultOutput,
@@ -14,7 +18,7 @@ export function repl({
   transpiler,
   onToggle,
 }) {
-  const scheduler = new Cyclist({
+  scheduler = new Cyclist({
     interval,
     onTrigger: async (hap, deadline, duration) => {
       try {