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FS#1645 - Add warning when opening file with 3D content

Attached to Project: QCAD
Opened by Martin (unknown-error) - Monday, 23 October 2017, 01:02 GMT+2
Last edited by Andrew (andrew) - Monday, 23 October 2017, 09:57 GMT+2
Task Type Feature Request
Category QCAD (main)
Status Assigned
Assigned To Andrew (andrew)
Operating System All
Severity Low
Priority Normal
Reported Version 3.18.1
Due in Version Undecided
Due Date Undecided
Percent Complete 0%
Votes 0
Private No



I’m working currently a lot with files coming from rhino. Qcad can open them properly any also most operations on them work as usual - except the selection methods.

box select from upper left to lower right works as usual.
double click to select all connected entities is broken. (only one entity is selected).
box select from lower right to upper left does not select entities touching the selection box. (nothing is selected)

on mac os nothing is selectable with single click.
on linux single click sometimes fails (nothing is selected after clicking on a line).

thanks for looking into this :)


This task depends upon

Comment by Husky (Husky) - Monday, 23 October 2017, 01:27 GMT+2

Hi Martin,

that isn't a bug of QCAD! You are trying to work on a 3D drawing in a 2D Application. QCAD can't handle appropriate the Z information.

Below Menu / Misc / Modify you will find a command which will convert this 3D drawing to a 2D drawing. The command is called "Flatten drawing to 2D"

Note: There is no way to convert this drawing back to a 3D drawing which will work later in a 3D Application.

Comment by Martin (unknown-error) - Monday, 23 October 2017, 01:39 GMT+2

Hi! thanks for the quick reply!

I agree on that qcad is not for 3D. However not knowing about the z index I just wanted to work in 2D. I don't know what's the best to assume for a user wanting to open a 3D file in qcad (actually most 3D dxf files are only flat drawings in z-layers anyways, so it's basically still 2D editing that's done on them. In my opinion there should be some info that a 3d drawing is opened or the z-information should be just ignored (not sure what that means for the code...).

I actually didn't know that the 3D-dxf was the reason for the "strange behavior" for quite some time until I figured it out (didn't know about the flattening though, thanks for the note!)

so maybe a kind of warning in the console could be useful when opening such file containing 3D data?