flowchart TB
    subgraph enc["one MTL4 render encoder, one tessellated draw"]
        direction TB
        vs["1 vertex shader<br/>points, rasterization off<br/>writes records"] -- "barrier<br/>vertex → object" --> hs["2 hull shader<br/>object function<br/>control points, factors"]
        hs -- "barrier" --> cnt["3 tessellator<br/>object functions<br/>count → prefix → emit"]
        cnt -- "barrier<br/>object → vertex" --> ds["4 domain shader<br/>vertex function<br/>indexed indirect draw"]
        ds --> ps["pixel shader<br/>render targets"]
    end
    note["Metal: no hull stage, no isolines,<br/>no point output; a compute<br/>encoder would split the pass"] -.-> enc