charge format stl

[Gio_S]

hello to all, I do not use autocad but intellicad (old, but enough) so I did not have the charge of the stl, and I wrote it.
this is the very first draft, still to be over-optimized and improved.
I was needed above all to be able to manipulate them by managing the low-level stl, which is why I built it myself, as a basic framework to expand with other features.
for now the "open" interface only finds files with the stl extension written in lowercase.
works only with stl ascii, and is therefore slow with large files, but it works, and seems a minimum robust even with stl lines formatted with variable spacing (certain programs do a little what they want).
I don't have the vl, this is why traditional acrobatics on strings.

 

[Gio_S]

fixed file opening problem that admits extension both "stl" minuscule and "stl" capital)
replace first line code with
(setq mystl (getfiled "select a stl file" "stl" 4))[il flag da 0 deve diventare 4]

 

[Gio_S]

final version of the stl loader.
note: requires stl file type ascii (not binary file type)
tested on dated intellicad, but should not give big problems on current autocad.
I also entered a small stl of example (open even with wordpad, stl ascii are simple text files).
Note 2, technique.
I preferred not to function the procedure on the three vertices, although in practice it repeats 3 times for each face.
First of all, for greater readability and ease of debug, second, because they are not convinced that in a continuous script jumps do well to the execution timing, but maybe I'm wrong. . .