Dxf code to identify types of surfaces.

[carlos_m_gil_p]

Hello boys how are you.

With what code dxf can I identify if an entity is a surface (loft), surface (network) or surface (Nurbs)

What I want is.
Select a surface with entsel.
And tell me what kind of surface it is.
But with DXF codes, not VL

Excuse my English, I only speak Spanish.
Thanks for the help.

[cadffm]

look into the dxf definition of you object:

(entget(car(entsel)))

Befehl: (assoc 0 (entget (car(entsel))))

Objekt wählen: (0 . "LOFTEDSURFACE")

Befehl: (assoc 0 (entget (car(entsel))))

Objekt wählen: (0 . "NURBSURFACE")

Befehl: (assoc 0 (entget (car(entsel))))

Objekt wählen: (0 . "LOFTEDSURFACE")

[carlos_m_gil_p]

@cadffm Hello how are you.

Thanks for answering.

Normally I do it like that.

But if you notice, the code of the surface (loft) and the surface (network) are the same.
And I do not know how I can identify which is which.

Thank you.

[cadffm]

If you compare group-0 you will see that is not clear enough for Loft and Network Surface

command: (assoc 0 (entget (car(entsel))))

(0 . "LOFTEDSURFACE")

(0 . "NURBSURFACE")

(0 . "LOFTEDSURFACE")

So  compare the xdata (Groupcode -3) of the objects: (entget (car(entsel)) '("*"))


(0 . "LOFTEDSURFACE")
(-3 ("ACAD_STEPID" (1071 . 5)))

(0 . "NURBSURFACE")
(-3 ("ACAD_SURFACE_XFORM" (1011 0.0 0.0 0.0) (1011 1.0 0.0 0.0) (1011 0.0 1.0 0.0) (1011 0.0 0.0 1.0)))

(0 . "LOFTEDSURFACE")
(-3 ("ACAD" (1000 . "AcDbLoftSurfaceType") (1070 . 2)) ("ACAD_STEPID" (1071 . 4)) ("ACAD_SURFACE_XFORM" (1011 0.0 0.0 0.0) (1011 1.0 0.0 0.0) (1011 0.0 1.0 0.0) (1011 0.0 0.0 1.0)))

!? one step further, we have a difference between Loft and Network Surface now.

[doaiena]

I know you said "not VL", but it is actually the easiest way. 

(vla-get-surfacetype (vlax-ename->vla-object (car (entsel))))

This is the output for the three surfaces in your file:

- "Loft with cross sections only"
- "NURBS"
- "Network"

Is there any particular reason you don't want to use VL?

[_gile · Accepted solution]

Hi,

Simple, without VL, you can try :

(getpropertyvalue (car (entsel)) "SurfaceTypeName")

[carlos_m_gil_p]

Hello @_gile

Thank you very much for your solution.

It's the best I've learned.
With this, it solves more than one problem I have.

Thank you very much everyone for your collaboration, too.