61 lines
1.8 KiB
JavaScript
61 lines
1.8 KiB
JavaScript
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import { createRenderStep } from './render-step.mjs';
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const stepsOrder = [
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"prepare",
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"read",
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"update",
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"preRender",
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"render",
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"postRender",
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];
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const maxElapsed = 40;
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function createRenderBatcher(scheduleNextBatch, allowKeepAlive) {
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let runNextFrame = false;
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let useDefaultElapsed = true;
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const state = {
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delta: 0,
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timestamp: 0,
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isProcessing: false,
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};
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const steps = stepsOrder.reduce((acc, key) => {
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acc[key] = createRenderStep(() => (runNextFrame = true));
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return acc;
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}, {});
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const processStep = (stepId) => steps[stepId].process(state);
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const processBatch = () => {
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const timestamp = performance.now();
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runNextFrame = false;
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state.delta = useDefaultElapsed
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? 1000 / 60
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: Math.max(Math.min(timestamp - state.timestamp, maxElapsed), 1);
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state.timestamp = timestamp;
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state.isProcessing = true;
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stepsOrder.forEach(processStep);
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state.isProcessing = false;
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if (runNextFrame && allowKeepAlive) {
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useDefaultElapsed = false;
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scheduleNextBatch(processBatch);
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}
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};
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const wake = () => {
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runNextFrame = true;
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useDefaultElapsed = true;
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if (!state.isProcessing) {
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scheduleNextBatch(processBatch);
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}
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};
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const schedule = stepsOrder.reduce((acc, key) => {
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const step = steps[key];
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acc[key] = (process, keepAlive = false, immediate = false) => {
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if (!runNextFrame)
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wake();
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return step.schedule(process, keepAlive, immediate);
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};
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return acc;
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}, {});
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const cancel = (process) => stepsOrder.forEach((key) => steps[key].cancel(process));
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return { schedule, cancel, state, steps };
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}
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export { createRenderBatcher, stepsOrder };
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