FAQ: PC Specific Issues

17.1 Which PC graphics card does AVS recommend?

AVS does not recommend any particular graphics card. AVS/Express is not customized or optimized for any particular graphics card. AVS/Express hardware rendering uses uses OpenGL, so it is important to pick a card with good OpenGL drivers. You can get information about the various PC graphics cards at :

PC World Graphics Board Review

We measure graphics performance in "teapots per second". You can do this by building the network: Read_Geom -> Viewer3D. Use Read_Geom to load teapot.geo. Then bring up the View Editor in the data viewer (selecting that option from the Editors pulldown menu). At the bottom of the "General" page is a toggle for "Timer". Turn it on.

Now spin the teapot for a while (at least 20 seconds or so) and then stop it (click in the view with the left mouse button). You have to "spin" the teapot so that it continues spinning - not just rotate it interactively. When you stop the spinning, a message will be printed at the VCP (express console) telling you how many frames were rendered per second.

Things change fast with graphics hardware! In early 1997 we measured around 15 frames per second with the faster PC cards. By comparison, in late 2001 we measured over 35 frames per second on a slow low-end card and over 300 frames per second with faster cards! We can't really quote a recommended performance figure as it would soon be out of date.

17.2 How do I debug a module in the user process on the PC?

Debugging the user process on the PC is similar to debugging under UNIX in that you must attach to a running process.

You attach to the process using its process ID (PID). Once the user process is running, you can determine its PID under NT, by doing the following:

  1. Call up the task manager by right mouse clicking on the taskbar, and then selecting task manager.
  2. Select the "Processes" tab in the task manager
  3. Locate the PID of the task you are interested in debugging (the user process)

BE CAREFUL because there is a windows NT process which is also called USER.EXE. Make sure you select the correct user.exe.

Under Windows '95, you can use Spy++ to find the PID:

  1. Bring up Spy++ from Start_Menu->Programs->Microsoft_Visual_C++_6.0.
  2. Select the menu item Spy->Processes..
  3. A window containing a list of processes, including the PIDs, appears. Note that the PIDs are high numbers on Win95.

Invoke the Visual C++ debugger, MSDEV, and specify the PID determined above as an option. Run:

MSDEV -p <PID>

This command can be run from either a command shell, or from the Desktop:
Start->Run.

17.3 Why do the dimensions of the picture I see on the screen differ from what is printed when printing on the PC with true scale enabled?

Microsoft provides some useful information on this issue at: http://www.microsoft.com/kb/articles/Q127/1/52.htm This article provides two manual methods for determining real output dimensions programmatically.

17.4 Under Windows 95, why are printouts from my color printer sometimes in black and white?

In Windows '95 your printouts will be in black and white -- even if you send them to a color printer -- if your default printer is a black and white printer. To get color printouts, you must make the color printer the default printer. You should also verify that you are using the correct driver for your color printer.

17.5 How do I resolve an 'out of environment space' error when trying to relink AVS/Express under Windows 95 or 98?

The default amount of memory allocated by Windows 95 and 98 for "environment" is not usually enough to execute the nmake for AVS/Express. To allocate more memory for the environment, add the following line to your config.sys file and reboot:

shell=c:\windows\command.com /e:4096


Note: "4096" may be a little higher than necessary. You can change this number to suit your needs.  You may also find that these lines will also work:

    shell=c:\command.com /e:4096

    shell=c:\command.com /e:4096 /P

    shell=c:\windows\command.com /e:4096 /P