sec commit

node_modules/framesync/lib/create-render-step.js

@@ -0,0 +1,55 @@
+export function createRenderStep(runNextFrame) {
+    let toRun = [];
+    let toRunNextFrame = [];
+    let numToRun = 0;
+    let isProcessing = false;
+    let flushNextFrame = false;
+    const toKeepAlive = new WeakSet();
+    const step = {
+        schedule: (callback, keepAlive = false, immediate = false) => {
+            const addToCurrentFrame = immediate && isProcessing;
+            const buffer = addToCurrentFrame ? toRun : toRunNextFrame;
+            if (keepAlive)
+                toKeepAlive.add(callback);
+            if (buffer.indexOf(callback) === -1) {
+                buffer.push(callback);
+                if (addToCurrentFrame && isProcessing)
+                    numToRun = toRun.length;
+            }
+            return callback;
+        },
+        cancel: (callback) => {
+            const index = toRunNextFrame.indexOf(callback);
+            if (index !== -1)
+                toRunNextFrame.splice(index, 1);
+            toKeepAlive.delete(callback);
+        },
+        process: (frameData) => {
+            if (isProcessing) {
+                flushNextFrame = true;
+                return;
+            }
+            isProcessing = true;
+            [toRun, toRunNextFrame] = [toRunNextFrame, toRun];
+            toRunNextFrame.length = 0;
+            numToRun = toRun.length;
+            if (numToRun) {
+                for (let i = 0; i < numToRun; i++) {
+                    const callback = toRun[i];
+                    callback(frameData);
+                    if (toKeepAlive.has(callback)) {
+                        step.schedule(callback);
+                        runNextFrame();
+                    }
+                }
+            }
+            isProcessing = false;
+            if (flushNextFrame) {
+                flushNextFrame = false;
+                step.process(frameData);
+            }
+        },
+    };
+    return step;
+}
+//# sourceMappingURL=create-render-step.js.map