buffers_suck.js

function render() {
    if (mappedBuffers.empty()) {
        buffer, ab = device.createMappedBuffer();

        bg = device.createBindGroup(buffer);
        buffer.bindGroup = bg;
        buffer.arrayBuffer = ab;
    } else {
        buffer = mappedBuffers.pop();
        bg = buffer.bindGroup;
        arrayBuffer = buffer.arrayBuffer;
    }

    populate(arrayBuffer);

    buffer.unmap();

    encoder = device.createCommandEncoder();

    passEncoder = encoder.beginRenderPass();

    passEncoder.setBindGroup(bg);
    passEncoder.draw();

    gpuQueue.submit();

    buffer.mapWriteAsync().then((ab) => {
        buffer.arrayBuffer = ab;
        mappedBuffer.push(buffer);
    });

    requestAnimationFrame(render);
}