flowchart LR
  subgraph before["before: each draw"]
    direction TB
    A1["cmd_draw<br/>table = e->render_table<br/>RETAIN"] --> A2["render_encoder()<br/>returns e->render<br/>RETAIN for the caller"]
    A2 --> A3["draw_state(enc)<br/>draw_bindings(table)<br/>draw_primitives(enc, table)<br/>RETAIN each parameter on entry,<br/>RELEASE on exit"]
    A3 --> A4["Metal draw call"]
    A4 --> A5["cmd_draw returns<br/>RELEASE its object locals"]
  end
  subgraph after["after: each draw"]
    direction TB
    B1["cmd_draw<br/>__unsafe_unretained table"] --> B2["render_pass_matches()<br/>plain C, no objects"]
    B2 --> B3["draw_state, draw_bindings,<br/>draw_primitives<br/>unretained parameters"]
    B3 --> B4["Metal draw call"]
  end
  before ~~~ after