Of course, I can create simple marker via something like

_m = create3DENEntity ["Marker", "rectangle", [3350,4500,0]];

This is not a valid marker as there is no class "rectangle" in CfgMarkers, you should get error

_m = create3DENEntity ["Marker", "mil_dot", [100, 100, 0]]; 
_m set3DENAttribute ["markerType", 1]; //Unsure if number or string (like setMarkerShape). Attribute returns -1 as default value and 1 or 2 for rectangle/ellipse
_m set3DENAttribute ["brush", "DiagGrid"]; 
 
[_m get3DENAttribute "itemClass", _m get3DENAttribute "markerType", _m get3DENAttribute "brush"]

Seems like markerType and brush have no effect. @BIS_fnc_KK

@R3vo can icon marker have brush or shape? Because 3DEN markers created as icons

@BIS_fnc_KK, I fixed misprint in the ticket additional info. And @R3vo has alredy described this correctly above.

In summary, any try to change icon marker to shape marker via changing "markerType" fails.
And you are right, it's not possible to create shape marker as there are no class "rectangle"/"ellipse" in CfgMarkers.

Note, for the markers created with GUI values "RECTANGLE" or "ELLIPSE" are being set for "markerType" parameter in "mission.sqm"!

So how to create a shape marker with a script only in Eden?

In T159074#2202136, @BIS_fnc_KK wrote:

@R3vo can icon marker have brush or shape? Because 3DEN markers created as icons

Well, for default makers one can simple create them without defining icon or shape and then decided if it's an icon or shape marker. With create3DENEntity this isn't possible so one has to set a marker to icon first.

Duplicate of https://feedback.bistudio.com/T159060

Fixed in revision: 147769

So how to create a shape marker with a script only in Eden?

m = create3DENEntity ["Marker", "", position player]; // default rectangle marker
m set3DENAttribute ["markerType", 1]; //0 - rectangle; 1- ellipse 
m set3DENAttribute ["brush", "DiagGrid"];