onwallpoly({polystuff})

[DustyPorViva]

It's been proposed before but not even acknowledged. Can we please get an onwallpoly({polystuff}) that returns the x/y of the onwall/notonwall intersections?
Attached is an example. Say the white lines are the onwallpoly checks(of course, invisible). The yellow dots is what is returned in an array in the form of:
this.onwall=onwallpoly({polystuff});
Then this.onwall would be:
{{firstx,firsty},{secondx,secondy}}
and so on and so forth. This would allow more complicated checks and systems(like cars, lighting effects and such) to be done without having to run long loops that slow down Graal.