Troubleshooting

Application experiences gopen errors.

HPSBV may not have been linked in, or the SPOOLED flag was not OR'ed in with the mode flag.

The archive file appears unexpectedly small or empty.

Graphics code may be non-polygonal output (such as polylines), or the gescape SBVESC_END_ARC was called.

Objects appear flat in the Personal Visualizer™ and have no depth to them.

Check code to see if data is created by polygon2d calls, rather than polygon3d, for example. You may also have to open the driver with the THREE_D flag.

Object file contains multiple objects I would like to deal with separately.

Try separating the data with 3-D Edit or use the gescape SBVESC_OBJ_NAME in your Starbase code.

Objects appear reversed in orientation when imported into the Personal Visualizer™.

Rotate them about Y by 180 degrees. The driver attempts to keep positive and negative points relative to their original coordinate systems when converting from left-handed to right-handed space.

Objects appear to project shadows with holes when rendered in the Personal Visualizer™.

Use the -b (create double-sided polygons) option in the sbvtrans translator. This will create correct polygons for shadow testing in the Personal Visualizer™.

The surface features of an object appear to be a mixture of smooth and faceted data.

There can be several reasons for this effect. If the -n (use Starbase normals) option from sbvtrans was used, then not all of the data had shading normals per vertex. If total smooth shading is desired, try using the -s option from sbvtrans. This will attempt to smooth the object data given the current epsilon setting (-e option). If this operation does not work to your satisfaction, try increasing the epsilon value to consider spaced out points closer in neighborhood. If only selective smoothing is desired, try smoothing the appropriate points through the 3D Edit editor in the Personal Visualizer™.

Objects appear to jump off the screen when scaled in the Personal Visualizer™.

Your objects require centering when they are first created. Use the centering option (-c) from the sbvtrans translator. If you have a group of objects which will remain grouped, use the (-c all) option to center the entire group in the archive.

sbvtrans complains about discovering syntax errors in the archive.

Usually this message appears when sbvtrans has encounted an unexpected end of file. The archive may have been created without properly closing the file descriptor with a gclose() call. The file may also be truncated due to a file system problem. If either of these problems occur, attempt to create a new archive file. (sbvtrans will output any geometry created up to the point of the error.)

Object faces appear to "pop" on and off in the Personal Visualizer™ while manipulating the geometry.

This model has been created with the normals (-n) option of sbvtrans. Certain Starbase normals may be incompatible with Personal Visualizer™'s implementation of vertex normals. Check to see that individual vertex normals are correct through 3-D Edit in the Personal Visualizer™. If the faces are wrong, fix them there. If they are correct, try recreating the model without the (-n) option to determine if a model without Starbase normals is correct. If all else fails and a smooth object is desired, try the -s option in sbvtrans. (Some popping may occur normally since Personal Visualizer™ vertex normals are used for backface rejection.) Also, if facets are non-planar, then Personal Visualizer™ assumptions about planar polygons may cause popping.

Object faces appear to be missing after using the smoothing option (-s) of sbvtrans.

Adjoining faces may be creating incompatible vertex normals for smoothing and backface culling. Try 3-D Edit in the Personal Visualizer™ to fix local cases or adjust vertex points of problem polygons not to be considered exactly adjacent in their Starbase database. Recreate the archive from the original application.

Objects appear white when imported into the Personal Visualizer™.

The HPSBV pipeline does not transfer color attributes to the Personal Visualizer™. The Personal Visualizer™ is an attribute driven application, i.e., object elements are separated by color attributes. Try using the gescape SBVESC_OBJ_NAME to partition HPSBV output by color. Import the separate objects into the Personal Visualizer™ and apply appropriate attributes.

Objects appear to be "inside-out".

Check original Starbase code for incorrect use of gescape SBVESC_RT_COORD. If this is not the problem, check to see if the correct vertex format statement is being used for clockwise/ counter-clockwise definitions. (Turning on hidden_surface culling during normal Starbase displaying will usually reveal the problem from Starbase.)

sbvtrans running out of memory.

Try running the translator on another machine where other large applications are not running. It is not advisable to run the translator and other large applications (such as the Personal Visualizer™) when extremely large archives are being converted.

Personal Visualizer™ complains that it cannot run the IMPORT script.

Set correct search path first. Use the command from the VIEW manager:

set path "$HOME/〈path-name〉"

before attempting to run IMPORT scripts.

Personal Visualizer™ complains that it cannot find objects in the IMPORT script.

The objects may have been relocated from the directories where they were originally created (along with script.) Do not relocate objects to new directories after IMPORT scripts are created since they contain absolute path names to all object files at the time of creation.

Objects don't appear in the current viewport after importation.

You may be required to reorient your scene cameras or scaling the geometry to a size which is relevant to the current view extent. Try scaling the objects very small and using the center object option in the View manager of the Personal Visualizer™. (Note: This option will only bring the object to the global origin. It will not re-center the data for scaling options described in the trouble shooting hint given in "jump off the screen"...Try centering your data with the options given in the sbvtrans translator.)

Object parts from an archive appear all at the origin.

If the centering option (-c) in sbvtrans is invoked, each object data file is centered independent of the rest of the objects in an archive. If an archive consists of an entire group, use the (-c all) option to center all objects as if one group.

Redundant copies of the object appear to be created in the same object.

Check your Starbase code to see that multiple definitions of the object database are not being output to the archive.

Curved surfaces seem to be coarsely faceted.

Try tuning the curve_resolution() function call parameters to improve output for spline surface, arc, and ellipse calls.

Object names imported with the IMPORT script do not match those given in the original gescape calls.

sbvtrans attempted to resolve possible name conflicts in an archive before creating output files. If the IMPORT script creates undesirable names, edit the script to create more useful names. These names, however, are limited to five (5) significant characters each. For example:

import wave "$HOME/data/partfile_a.obj" to partA

becomes

import wave "$HOME/data/partfile_a.obj" to brake

I don't remember the sbvtrans command I used to translate a particular archive.

Examine the IMPORT file created from translation. It contains a copy of the command line along with the date the archive was translated.

My data contains concave polygons...will they render correctly in the Personal Visualizer™?

The Personal Visualizer™ expects planar, convex polygons to render geometry correctly. If a facet is concave and/or twisted to be non-planar, try redefining the face in the Personal Visualizer™ model editor as a group of triangular facets.

Data imported into the Personal Visualizer™ does not appear the same way as it did in Starbase (view, clipping, etc...)

Data transferred to the Personal Visualizer™ through the SBV device driver breaks the display transformation pipeline before any view transforms take place. Viewing transforms are applied interactively in the Personal Visualizer™, so it is best to imagine the Personal Visualizer™ as the completion of the entire viewing/clipping pipeline to the SBV driver, i.e., the Personal Visualizer™ handles the display tasks normally taken care of by Starbase.

My program makes partial polygon calls to create holes, but none show up in the Personal Visualizer™.

Partial polygons output data which cannot be properly rendered by the Personal Visualizer™. Use the polygon "holes" to redefine new surrounding polygon meshes in the model editor if "holes" are necessary.

The tessellation of my spline surfaces appears uneven.

As a virtual 3-D driver, it makes no sense to use the screen-based flags DC_VALUES, VDC_VALUES, or METRIC for the function curve_resolution() (although they will work). Use the coordinate type STEP_SIZE to create uniform partitioning over an entire surface in modeling coordinates.

How long must I keep SBV archive files and any of the files created by the translator?

After data has been successfully imported into the Personal Visualizer™, it is not necessary to retain any of the archive or translator files unless the Personal Visualizer™ versions need to be recreated.

I've written a system call to sbvtrans from my application and would like to cancel its output to the console.

From the language C, using the command system() requires concatenating the following to your command line ^[1] .

sprintf(cmd, "sbvtrans %s -n -c all", archive);
strcat(cmd, "-q 1> 〈dev〉/null 2> 〈dev〉/null");
system(cmd);