T3D @ WWW: FAQ

• Q: How can I get to the top T3d @ WWW page?
  
  A: Click on the T3d@ icon in the upper right corner of each page.

• Q: Which fields in the T3d job upload form are optional and which not?
  
  A: Generally, no from the form fields must be filled in. If you do not specify any input file, or if you specify just the verification of an input file, your job is processed immediately taking into account the used command line options with output directly to your web browser. In such a case, the email address is ignored. If no input file and no options are specified, the T3d usage is printed (this is equivalent to -h option). If a T3d input file is given and its verification is not required, the job is appended to the job front, from which the jobs are released to processing on the first-in first-out basis. If the email address (or more addresses separated by spaces or commas) is specified, you will be notified about the completion of the job by an email. You are strongly encouraged to use this feature. Note that the -i and -g options are generated automatically and you do not have to specify them manually. Similarly you can avoid manual specification of -o and -x options by checking appropriate from the output check boxes.

• Q: How can I get to the job results if I forgot the T3d job identification number?
  
  A: If you had specified the email address when uploading the job you can find the T3d job identification number together with URL of the results in the notification email (if not deleted yet :-). Try to pick up the right message if you had processed more jobs. If you had not specified the email address you have no chance to get to the job results at all.

• Q: How long is my job going to wait in the queue?
  
  A: This is hard to say. The jobs are executed at selected times only. The number of executed T3d jobs depends on the number of jobs in the queue. With respect to current setting of the queue manager it could take from 1 minute to 2 hours. You can contact me if your job is pending in the queue for more than 24 hours.

• Q: I am repeatedly trying to upload a T3d job each time with the same error message
  
  There are now too many uploaded T3d jobs. Please, try it later !
  
  Is there something wrong?
  
  A: Maybe yes, maybe not. Either it is possible that someone is trying to overload the server or (which is more likely) the queue manager does not work properly and the jobs are pending in the queue without a chance to be processed. You can contact me if you are likely to loose your patience soon.

• Q: I cannot upload even a very small job each time getting this error message
  
  There is now too much disk space consumed by T3d jobs. Please, try it later !
  
  What can I do about that?
  
  A: Nothing. The disk space occupied by all the T3d jobs (also those being already processed and waiting for removal either by the user or by the system) is limited. Until any of the jobs is deleted you are not allowed to upload further one(s). You are therefore strongly encouraged to download the job results to your local machine and to remove them from T3d server.

• Q: I am getting T3d error message like this
  

  20:09:06 --> Input error (file t3d.in, line 7)
  (routine t3d_input_vertex, file input1.c, line 585)
  Zero mesh size specification detected at vertex 1
  

  What is wrong?
  
  A: A positive element spacing must be assigned to all vertices and control points defining curves and surfaces. If you do not specify this spacing directly in the input file you have to use the -d option on the command line to specify the default element size which is then used by all vertices and control points with no explicitly prescribed element size in the input file. Failure to supply the appropriate -d option usually results in the above error message.

• Q: I am trying to create my own T3d input file. However it is quite discouraging to wait each time for the job to be processed and to discover that I still did not manage to fix all the errors in the input file. Is there a way to go around and speed up the thing a little bit?
  
  A: Sure, you just have to check the input file verification box in the T3d job upload form. Your job will be then processed immediately but without generating the mesh (even if your input file will be OK). After fixing all the errors you have to submit the job without the verification request to get the mesh.

• Q: When prescribing graphic output I can't enforce -y 3 option (documented in T3d guide as VTK output). Instead, -y 2 option (corresponding to VRML output) is always used. Isn't there an error?
  
  A: Not in this particular case. T3d @ WWW supports only the VRML graphic output. Use -h -P options (without specifying any input file) to see the available options and their permissible parameters (relevant for T3d @ WWW).

• Q: I would like to use background grid for element spacing control? Is there a way how to do it?
  
  A: Unfortunately not. T3d @ WWW does not support mesh size control using the background mesh. The -m and -a options (documented in T3d guide) are disabled (and filtered out from the options). Use -h option (without specifying any input file) to see the available options relevant for T3d @ WWW.

• Q: How large mesh can be generated?
  
  A: The size of the mesh is limited by the amount of memory (currently set to 25 MB) consumed by T3d. This allows to generate 2D meshes up to approximately 70.000 of triangular elements and 3D meshes up to approximately 75.000 of tetrahedral elements.

• Q: I bookmarked the page with the results of my successfully completed job but it seems to not exist any more. When trying to display the results using the job identification number I am getting this error message
  
  T3d job 15413 not found
  
  How can I get to the results?
  
  A: The results of the job are stored at least for 3 days after its completion. After that the job and its results are deleted by the system and the result page becomes invalid. Download the job results to your computer within these 3 days if you intend to use them later.

• Q: My web browser does not display the output file of the completed T3d job. I have always to download it to my computer. How can I view the output file without downloading it?
  
  A: It seems that you are using MS Internet Explorer. You might experience a similar behaviour also for other files produced by T3d and for the input file as well. The problem is caused by associating a specific software (application) to handle files with specific suffix. You may try a different web browser or to deactivate the association with the appropriate suffix.

• Q: I cannot visualize the generated T3d mesh in my web browser. By clicking on the VRML link on the results page I see the VRML source only. Should I install some software?
  
  A: Yes, you should install a VRML plug-in or an external VRML viewer (invoked for x-world/x-vrml mime type). There are many VRML viewers available on the web.
  (I am sorry, but the link to list of VRML viewers on www.web3d.org is not functional any more.)

• Q: When viewing the mesh in my VRML viewer I see only the solid surface without the element contours. How can I see the mesh edges or elements?
  
  A: It seems that your VRML viewer does not support the wireframe mode. In this case you should use -z 1 option when uploading the job to generate the wireframe VRML file directly by T3d.

Copyright © by Daniel Rypl 2002