scope (global) [
    [pixel__ps_ps_main]  : (position : float4) -> float4
    [vertex__vs_vs_main] : (position : float3) -> float4
    scope (vertex__vs_vs_main) [
        [position]           : float3
    ]
    scope (pixel__ps_ps_main) [
        [position]           : float4
    ]
]