/**
* Prepares the render-instruction buffer to be populated with instructions.
+ *
+ * If the render task is a render-once framebuffer backed by a native image,
+ * then this method will ensure that a GL sync object is created to track
+ * when the rendering has finished.
+ *
* @param[out] instruction to prepare
* @param[in] updateBufferIndex The current update buffer index.
*/