(2020-05-23, 12:53)Lasse Deleuran Wrote: I have run into issues with a user who has used LDCad to create instructions with BUFEXCH commands, see: https://github.com/LasseD/buildinginstru.../issues/34
As you can see, the issue appears to be a lack of "0" prefixes in the buffer-exchange-specific regions, causing LDCad to output files that are not interpreted correctly in software that does not support Buffer Exchange commands.
Can you please share the specification which you have used for the existing support, and are you aware of other commands in LDCad which might cause other software to render stuff incorrectly?
I'm not sure I understand the problem, do you mean you expected the "0 " prefixes on the ghost lines to be added automatically ?
If so that's not part of the bufxchg spec.
0 GHOST is a different mlcad meta, which it uses to draw parts transparently I believe.
It is just added as a prefix to lines which the user wants 'ghosted'.
I used MLCad's documentation to implement bufxchg
http://mlcad.lm-software.com/e_default.htm
It is basically a stack command, meaning you store the whole LDraw content at the STORE point and trow away the current content upon a RETRIEVE.
I did implement it as a hide flag in LDCad as I don't want to literately delete stuff
The main trick is to loop backwards trough the LDraw lines when processing the commands, that way nested ones are automatically handled correctly.