Notes and DisclaimerThe following FAQ entries were scraped off actual student postings from the the CS 4731 class. It is anticipated that students will tend to have the same problems over and over and this FAQ will help answer some of the issues that come up year over year. Where possible, I have kept the actual names of the students who posted to the message board, purely to give them credit. If your name appears and you would like me to take your name or your post off, please send me email. Also, the FAQ is provided purely to help. I haven't verified the accuracy of the suggestions, so please use at your own risk
Getting Started in OpenGL Issues
- If I want to use Cygwin to do my CS 4731 Projects, what do I do?
- How do I use Microsoft .NET for the CS 4731 projects?
- I am still having problems getting Visual Studio .NET to compile
- How can I work from home using text-based SSH and XWindows?
- Is there any help for using DevShed to develop OpenGL programs?
Problems on CCC Machines
Problems with book code, questions, Typos and Omissions from Textbook
Getting Started in OpenGL Issues==============================CUT =========================================== Question: If I want to use Cygwin to do my CS 4731 Projects, what do I do? Answer: Warning: the following is not for the faint of heart. Cygwin is ridiculously useful when it works, but almost always requires tweaking, and that tweaking requires low-level knowledge of both the Windows and *nix environments. If you're not very comfortable with all of the technologies involved, I would recommend trying XWin first. If you're having problems with xwin, it is possible to install XFree86 on Windows using the Cygwin installer. When setting it up, make sure that at least the 'Default' component set of XFree86 is being installed, as well as OpenSSH (under the Net category.) The attached batch file assumes that you installed cygwin to \cygwin. You may want to overwrite your \cygwin\usr\X11R6\bin\startxwin.bat with this file as well. It will start a 'transparent' X session so that X windows will act as regular Microsoft windows (no pun intended, I swear). If you installed OpenSSH with Cygwin, you can now run ssh -X -C email@example.com and X11 forwarding and compression will be enabled. You can rename the attached batch file and tack that line on to the end and have it proceed automatically. If it's working, the X logo will be displayed in the system tray. Right-click to display the root window (you should not have to do this except if you want to run a different window manager) or to exit. As a side note, you can modify that batch file to display all X windows as children of a root window, or to use a different window manager (such as twm) than Windows. The advantage of those methods would be easier differentiation between Microsoft windows and X windows. With offcampus 600kbit DSL and no compression, I pull one frame every 21 seconds. With compression, I pull one frame every five seconds. Either way, utterly masochistic for anything other than final debugging, especially because OpenGL that compiles and links on one platform should be identical to OpenGL compiled and linked on another platform (well, at this level of OpenGL anyways ;). If you enjoy pain, try running XEmacs at that level ;) Alexander Lash firstname.lastname@example.org =============CUT ================================================= Question: How do I use Microsoft .NET for the CS 4731 projects? Answer: GLUT/OpenGL problems: Here's a tip from Paul Tessier (grad student) for anyone using Visual Studio .Net This might be helpful to anyone use visual studio. WPI currently provide the .Net edit of visual studio and as such, when compiling you receive an error about redefining exit. It might be helpful to include these instuctions in the current help page. http://students.cs.tamu.edu/jwf4661/441/glut_NET.html ================================= CUT ============================ Question: I am still having problems getting Visual Studio .NET to compile Answer: .NET problems: Are you having difficulty installing the GLUT libraries? VS .Net keeps the libraries in a different location. If you put the GLu and GLUT headers/libraries into the VC 6.0 location, you probably won't get it to compile. If you are using VS .Net make sure to put the files in:
\Vc7\PlatformSDK\[include\GL,lib] - Paolo Piselli (TA) ================================= CUT ====================================== Question: How can I work from home using text-based SSH and XWindows? Answer: In case you want to use a text-based SSH client outside of WPI for speed, but still want to confirm your pictures look ok, visit http://www.cs.umn.edu/help/offsite/graphical.php. This will tell you how to get xwin (available free from WPI) to open and display whenever a graphic is sent from SSH. ================================= CUT ====================================== Question: Is there any help for using DevShed to develop OpenGL programs? Answer: Hey guys, I was finally able to get DevShed to work. Follow the instructions on this site and you'll be all set. http://www.cs.auckland.ac.nz/~jli023/c/bloodshed.htm -- Greg Ratner
Problems on CCC Machines==================== CUT====================================================== Question: The rand( ) function on the CCC machines is not working Answer: rand() not working on CCC machines: From Brian Corcoran: Both rand() and random() are in stdlib.h on the CCC machines: #include
should work. Type 'man rand' or 'man random' for more info. And from Steven Gogos: try #include [cmath] also, you may have to wrap it in a #ifndef WIN32 so you do not get truncation warnings with msvc++ on your machine
Questions, Problems with book code or Typos and Omissions from Textbook===========================CUT==================================================== Question: Problems compiling book code under linux or program complains of glGenVertexArrays under Linux Answer: The starter code (as well as many of the examples from in your textbook) actually use OpenGL 3.2. Under linux GLEW segfaults with 3.2 when call glGenVertexArrays, the vertex array objects are not supported. There are three fixes for this: a. the first is switch to OpenGL 3.1. VAOs apparently only work with GLEW for OpenGL 3.1. b. The second fix is to put glewExperimental = GL_TRUE; before the call to glewInit(); c. The third is to use glext instead of GLEW. Option (b) seems to be the easiest. In some extreme cases, you may have to try all three options. Enjoy! Emmanuel ===========================CUT====================================================
C/C++ Questions========================CUT =============================================== Question: What's the ascii value of the escape character? Answer: Finding out the escape character: From Vince Bullinger: Using this little (18 lines) program I wrote - it's attached - you can test values of almost all characters. Escape is 27.