Communication through multiple instances of Autocad

[Serhan_BAKIR]

Hi there,

I wonder if it is possible for vlisp to communicate with another instance of Autocad?? Since its possible to attach to 3rd party applications through com interface, can we utilize this inorder to run multiple Autocad sessions in parallel and work together? Handling huge lists would be faster if we could use multiple instances on multiple cpu cores! Since Autodesk won't seem to work on parallel processing for Acad we need to do something come on guys

[dgorsman]

I am thinking that any savings on time will disappear in the delays communicating between separate programs and eventual max'ed out RAM useage. Better option for dealing with long delays is to re-evaluate the algorithm and optimize for minimum amount of duplicated calculations, enable early exit conditions, pre-sorting, improved logic, etc.

[Serhan_BAKIR]

Is it doable? In theory?

[dgorsman]

Without looking too deeply into it, I'd say no. Using COM to get an active session of AutoCAD doesn't allow for discrimination between multiple sessions of the same program it just gets one (the first started?). To my mind, best investment along those lines is developing skills for creating true multi-threaded programming with the higher-level languages and using them to develop the needed tools.

[BlackBox]

To my mind, best investment along those lines is developing skills for creating true multi-threaded programming with the higher-level languages and using them to develop the needed tools.

1+

That's why I've started to jump from Visual LISP (which I enjoy) to .NET API, and ultimately to ObjectARX (C++ for AutoCAD).

Visual LISP still has the higher level language beat in areas; which is why most of my .NET development (to date) is making .NET functionality available to LISP via LispFunction Methods. LoL

[dgorsman]

Exactly. Most of my dotNET work include a separate class for defining the LISP wrapper methods so it can be used by the "real" programming . I probably should create a template for that somewhere...

[BlackBox]

Exactly. Most of my dotNET work include a separate class for defining the LISP wrapper methods so it can be used by the "real" programming . I probably should create a template for that somewhere...

[Serhan_BAKIR]

Ok i got your point.. So are there any multi-threaded routines (arx/.net) out there to test some basics of the parallel processing idea. I know before even learn to crawl its not wise trying to run but if Im at a bottle neck point I would like to see the other bottles neck. İ'll be happy if you can point me to a direction, a related forum topic maybe.

[Serhan_BAKIR]

Please let me mention another related problem. I'm running some computation based lisp routines and time consuming tasks make my win7_32bit acad2011 environment fall into not responding state (faded screen turning circle).

I cannot sense the difference whether code really stuck somewhere or it’s running properly.
As far as I understand Vista and 7 operating systems do not tolerate threads running on so called UI level.

Will it do any good if I could create a background instance of acad.exe where computation takes place and be able to follow the progress from the main application? If so how can I achieve that?
pressing esc doesn't cancel. acet-ui-progress and opendcl progress bars aren't working as expected due to screen fading out.

Screen recording shows the behavior of a simple counter.
(setq i 0)(while (< i 1e6)(setq i (1+ i))(princ (strcat "\n" (itoa i))))

[dgorsman]

As I mentioned earlier, the first best option is to re-evaluate your algorithms. Chances are you are taking a brute-force approach which likely incorporates a number of redundancies. Something more elegant can usually take care of most of those problems.

Multi-threading is very tricky inside AutoCAD. You can't multi-thread using anything directly connected to AutoCAD but can create threads for your own custom processes. But for the life of me I can't think of anything that would really required that kind of power.