Playing around with laying one dxf drawing over another for comparison.
It looks to me that 'Import Block' and selecting a dxf file works OK, provided that the Construction Layer is not in use in the drawing imported.
If the construction layer is in use, strange interactions occur.
So, my approach is:
- edit both the current and acquired drawings to move all content of the construction layer to another named layer,
- import acquired drawing to current drawing as a block,
- explode the acquired drawing block,
- sort out the insertion point offset.
Good to go with all layers from current and acquired drawings in place, nothing in the construction layer.
Then can re-arrange as required.
Do you mean Layer 0 with the Construction Layer? In LibreCAD any layer can be made a construction layer, with lines extending endlessly. Is it an AutoCAD convention that Layer 0 is the construction layer?
I have never played much with importing drawings and layer issues, but have always wondered what would happen for instance with same-named layers and expected it to become fiddly. It's fine you report your experiences. Should be somewhere at tips and tricks / techniques.
Is it an AutoCAD convention that Layer 0 is the construction layer?
No, layers named 0, 1, 2, etc. are conventionally for objects. This drafting guide for manual drafting and AutoCAD provides a good overview of all the conventional layers and line types for CAD drawings:
Did some more testing.
The confusions only arise with layers having the same name.
It appears I have mistakenly called Layer '0' the construction layer.
Thanks for the reference to the drafting manual, another level of knowledge gained
My approach is to have nothing in layer '0' when importing, and to manage the layer names in the source and destination files.
If combining layer content is desired, the same name works fine.
If it is desired not to combine content, just re-name either the source or destination layers.
Then importing as a block and exploding all works fine, and no confusions.
Without exploding, Layer 0 seems to contain all the content.
Partial exploding with layers turned off is an area of exploration yet.
With an ordinary drawing, the insertion point when importing is the origin (0,0).
Not sure how to handle arbitrary insertion points.