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General


What is Geomview?

A general purpose interactive viewing program for Unix. It is used mostly for 3D graphics but can display data in 2D and 4D as well. See the overview for more general comments about Geomview.


How do I download Geomview?

Geomview is available for free from http://www.geomview.org/download. There are binary distributions for Linux, FreeBSD, SGI, Sun SPARC, HP-UX, IBM RS/6000, DEC Alpha, and NeXT machines, as well as a source code distribution.

You can also download it via anonymous ftp from ftp://ftp.geomview.org/pub

Geomview is free software, but we like to hear from people using it. Please send us mail telling us what you're doing with it.


What Geomview documentation is available?

See the Documentation part of this web site.


How can I get in touch with other Geomview users?

There is a "geomview-users" mailing list for people using geomview that can be used for communication between users regarding geomview problems, questions, experiences, etc. The geomview authors are also a part of this list and will respond to questions posted to it. We also use this list to make announcements about new releases and other things of interest to users. To join the list, send an empty note with 'subscribe' in the subject line to geomview-users-request@lists.sourceforge.net, or visit the list web page at http://lists.sourceforge.net/mailman/listinfo/geomview-users.

See also the list of third party software and projects.


Configuration / Installation / Execution Problems


The checkboxes and certain other GUI widgets are either absent from Geomview's panels, or don't work when I compile the latest version. What's up?

This problems seems to be associated with recent versions of Lesstif (e.g. 0.91.x), at least on GNU/Linux. I don't know if it's a problem with Lesstif itself, or if something is wrong with the way Geomview uses Lesstif. In the meantime, if you experience this problem, I suggest compiling Geomview with Open Motif instead of Lesstif. There's a lightweight binary distribution of Open Motif 2.1.30 available from the Geomview download page, with instructions for using it with Geomview. Or, you can get the full Open Motif distribution (source or binary) from either http://www.opengroup.org/motif or http://www.openmotif.com.

If you're familiar with Lesstif and know what might cause this problem (and especially if you know how to fix it!), please email me [mbp@geomtech.com].


configure claims it can't find OpenGl on my system, but I'm sure that it is installed


configure claims it can't find Motif (or Lesstif or OpenMotif) on my system, but I'm sure that it is installed

Read all the suggestions above in the answer to the analogous question about OpenGL; they all apply equally well to Motif. (The main header file to look for in the "include" directory is "Xm/Xm.h").


Platforms


What platforms have binary downloads available?

SGI Irix, Linux, FreeBSD, Solaris, SunOS, HP, IBM RS/6000, DEC Alpha


There isn't a binary for my workstation. Is there hope?

Certainly. If your workstation has the X Window System, OpenGL, Motif, and an ANSI (ISO) C compiler, you can compile geomview from the source code distribution at http://www.geomview.org/download.

Note that there is a free version of OpenGL called Mesa (www.mesa3d.org) which runs in software on most of the free Unixes. See that page for details on the ongoing efforts to incorporate hardware support for some of the popular graphics cards.

Note also that there is a free version of Motif called lesstif (www.lesstif.org).

The INSTALL file has instructions about how to port to new architectures. If you have problems, send mail to software@geomview.org. If you succeed, we would appreciate receiving a copy of your "makefile/mk.whatever" and hearing about what source modifications were necessary. Ideally we'd also like to include your binaries in our precompiled distribution list.


Why isn't there a Windows versions?

There is not a native version of Geomview for Microsoft Windows. The main reason for this is that at the time when Geomview was written, personal computers were not fast enough to make interactive 3D graphics feasible so we focused our efforts on Unix workstations. By the time fast-enough PCs came around, the Geometry Center, where Geomview was developed, was in the process of being closed. The staff started work on a port to Windows but was not able to finish it before the Center shut down.

Geomview can run under Cygwin, which provides Windows with a Unix-alike environment. See Geomview for Windows? for more information.

If you would like to see a version of Geomview for Windows, you can contribute to its development in several ways. See Contributing to Geomview for details.


How fast does Geomview run on various platforms?

The current speedtest result file is now quite out of date. You can test Geomview on your own platform using the files found in data/speedtests. Please contribute your timings back to us so that we can update our master file with results for modern machines.


What happened to the NeXT Quick Renderman version?

We no longer distribute the NeXTStep/OpenStep version of Geomview, which used the Quick Renderman graphics library. We did this just to simplify code base maintenance after version 1.5.0. Fat binaries for Motorola, Intel, and HP-PA architectures for version 1.5.0 are still available.


I have access to an X11 and SGI workstation. Which version should I use?

The SGI version will almost always be significantly faster, due to hardware support for 3D graphics. For example, a Sun Sparcstation 10 is slower than an Indy (SGI's old entry level machine). In the future there might be hardware support for certain OpenGL graphics cards available on some of the PC Unixes.


What modules are shipped for which platforms with the current release?

We release almost all external modules for all platforms. The list of distributed modules is in the README file included in the distributions. If the module you want is in that list but doesn't appear in the modules list on main panel, Geomview probably wasn't installed properly. Note that there are additional modules written by others which are not part of the main distribution. The modules distributed in the most recent version of Geomview (1.6.1p9) are:

MODULE		DESCRIPTION
addbbox		explicitly create enclosing bounding box
animate		flip through a sequence of objects
clipboard	cut, copy, and past geometric objects
cplxview	visualize graphs of complex functions
drawbdy		compute and draw boundary of an object
emodule_wish	????
example		sample module Example2 described in manual
flythrough	interactive version of "Not Knot"
		hyperbolic flythrough
ginsu		interactively slice objects with movable
		clipping plane
graffiti	draw line segments on objects
gvclock		3D clock, demonstrates real-time motion
hinge		hinge copies of a polyhedron around its edges
maniview	3-manifold viewer
nose		demonstrates picking
stereo		hardware, crosseyed, or red/cyan stereo (beta)
sweep		generates objects of rotation from line segments
tackdown	redefine an object's "home" position
transformer	explicitly control (and see) an object's
		transformation matrix

The following modules use tcl/tk:

MODULE		DESCRIPTION
3D-Snapshot	create 3D snapshot of N-dimensional object view
Colormap	create colormaps for N-dimensional objects
Crayola		interactively color objects per-vertex
Labeler		generate polygonal (or vector) text from string
NDdemo		N-dimensional viewing demonstration
NDview		N-dimensional viewing controls and demonstration
Slicer		clip N-dimensional objects to hyperplanes
StageTools	suite of tools for making MPEG/video/etc animations 

The following modules are only included in the SGI distribution:

MODULE		DESCRIPTION
trigrp		explore triangle symmetry groups

The following utility programs are also included in the distribution:

UTILITY		DESCRIPTION

anytooff	convert one or many OOGL files into a single
		OFF file
anytoucd	convert an OOGL file to UCD (AVS) format
bdy		compute boundary of an object (helper for drawbdy)
bez2mesh	dice BEZ file to list of MESHes
clip		clip objects against plane/sphere/cylinder
		(helper for ginsu)
hvectext	generate vector text object
math2oogl	convert Mathematica graphics to OOGL
		(helper for OOGL.m)
offconsol	polylist vertex consolidator
offcvt		convert between ASCII and binary OFF format
oogl2rib	convert OOGL to Renderman RIB format
oogl2vrml	convert OOGL to VRML 1.0
polymerge	merge degenerate OFF vertices/edges/faces
		(to Evolver or OFF)
togeomview	send commands to geomview
ucdtooff	convert UCD (AVS) format to OFF format
vrml2oogl	convert VRML 1.0 to OOGL


What modules are no longer included in the distribution and why?

MODULE	  	DESCRIPTION

4dview		4-dimensional slicing & rotation
pssnap		generate PostScript snapshot
warp		interactively deform an object
4dview was replaced by the more general NDview, and its custom viewpoint selector widget was only usable with the SGI version of Forms.

The functionality of pssnap has been directly incorporated into Geomview, and is available through the Save panel: one of the options is Save As Postscript.

The warp module used Forms and wasn't converted to XForms like the others. I'm not sure what the problem was.


Using Geomview


Why don't objects appear in the right places?

When objects aren't appearing where you think they should, it's probably because normalization is on by default. Normalization simply scales an object's bounding box to fit into a unit sphere, with the center of the bounding box translated to the origin. This is useful when examining a single object, as you can easily view the whole object without having to worry about how big it is. However, it also means that if you're loading multiple objects that are supposed to belong in the same coordinate system, all the objects will be scaled and placed at the origin. To turn off normalization, bring up the Appearance Panel. The normalization controls are in the lower-right quadrant of the panel. Select the "None" option. The alternate hotkey shortcut is '0N'.

To turn off normalization by default, customize Geomview by inserting the line (normalization allgeoms none) into a file called .geomview in your home directory.

When you turn off normalization your objects might seem to vanish. This is because the unnormalized objects do not lie in the camera's viewing cone. The easiest way to see everything is to choose the "World" object in the Object Browser, then click on "Look At" in the Tools Panel.

Why is everything centered and/or on top of each other?

See previous answer.


How can I display a collection of points?

The most efficient way to display points in Geomview is to use the VECT file format. This file format is mainly used for building shapes made out of lines but we can also use it to specify lines that contain only one vertex (i.e. points). Let's take a look at an example VECT file that describes 3 points colored red, green and blue:
VECT
3 3 3      # num. of polylines, num. of vertices, num. of colors.

1 1 1      # num. of vertices in each of the 3 polylines,
           # in this case only 1 for each since we are doing points.

1 1 1      # num. of colors supplied for each polyline.

-1 -.2 0   # Here are the coordinates of each point.
 1 -.2 0
 0  .9 0

1 0 0 1    # Color for each vertex in RGBA format.
0 1 0 1
0 0 1 1
When loading this file into Geomview, you will probably need to turn off the bounding box (via the appearance panel), otherwise you may not be able to see the points.


How do I make the points larger?

By default, the thickness of lines and points in Geomview is 1. This may be okay for most lines, but it causes each point to occupy only one pixel on the computer screen. You can change line and point thickness by adding an appearance tag to the top your geometry file that looks like this:
appearance {
    linewidth 4 
}
In this case, we have increased our line/point size to 4 and any points we have in our file will now appear as small disks. You can also change the line width using the Appearance panel. What Geomview actually does is render each point as a many sided polygon which approximates a disk.

If you want the points to appear as solid 3-dimensional objects, such as tiny spheres, you can use a completely different method for representing them: an INST object with multiple transforms. This lets you specify an arbitrary geometric shape to be used to represent the points. For example, the following file represents the three points (1.5, 2.0, 0.1), (1.0, 0.5, 0.2), and (0.5, 0.3, 0.2) using small cubes:

INST
geom {
  OFF
  8 6 12
  -0.05 -0.05 -0.05
   0.05 -0.05 -0.05
   0.05  0.05 -0.05
  -0.05  0.05 -0.05
  -0.05 -0.05  0.05
   0.05 -0.05  0.05
   0.05  0.05  0.05
  -0.05  0.05  0.05
  4 0 1 2 3
  4 4 5 6 7
  4 2 3 7 6
  4 0 1 5 4
  4 0 4 7 3
  4 1 2 6 5
}
transforms
1 0 0 0  0 1 0 0  0 0 1 0  1.5 2.0 0.1 1
1 0 0 0  0 1 0 0  0 0 1 0  1.0 0.5 0.2 1
1 0 0 0  0 1 0 0  0 0 1 0  0.5 0.3 0.2 1
#
# these are the matrices:
#
# 1   0   0   0     1   0   0   0     1   0   0   0
# 0   1   0   0     0   1   0   0     0   1   0   0
# 0   0   1   0     0   0   1   0     0   0   1   0
# 1.5 2.0 0.1 1     1.0 0.5 0.2 1     0.5 0.3 0.2 1
The OFF object between "geom {" and "}" is the cube. The three lines after the word "transform" are 4x4 transforms, one for each point. Note that you can use any valid OOGL expression for the geometry; for example, if you want to use small dodecahedra to represent points, you could repace the above OFF object with the following, which references the dodecahedron object in the file dodec.off (distributed with Geomview), scaling it by 0.05:
INST
geom {
  INST
  geom { < dodec.off }
  transform
    .05   0   0   0
      0 .05   0   0
      0   0 .05   0
      0   0   0   1
}
transforms
1 0 0 0 0 1 0 0 0 0 1 0    1.5 2.0 0.1  1
1 0 0 0 0 1 0 0 0 0 1 0    1.0 0.5 0.7  1
1 0 0 0 0 1 0 0 0 0 1 0    0.5 0.3 0.2  1
Be aware that the more complicated the geometry you use for your points, the longer it will take Geomview to refresh the window. This can be important if you're dealing with a large number of points, in which case you should stick to very simple point shapes or use the method of displaying points in VECT format.


How do I put text into a scene?

You have two options:

  • You can use the Labeler external module, which gives you a GUI for typing text and selecting the font: either vector or a polygonalized version of an installed font. However, you need to position the text in the 3D scene, either by hand or with some other module like Transformer.

  • You can use the hvectext command-line utility program for Hershey vector fonts, which does let you specify a position for the text. You would then need to load the resulting file into Geomview.

If you don't need the text to be a 3D object in the scene, you can create an image or postscript file of the scene and then use an image editor such as Illustrator, Showcase, or XPaint to annotate it with text.


Can Geomview do volume visualization?

No, Geomview is intended to do surface visualization. You can either create an isosurface and then view it using Geomview, or use a volume visualization package. The free vtk visualization toolkit has extensive support for volume visualization, as do commercial packages like AVS, Iris Explorer, or IBM Data Explorer. Volvis is free software specifically for volume visualization.


Can Geomview do texture maps?

Yes, in release 1.6 and higher, but only in the OpenGL version, not in the X11 version.


Why can't Geomview read my OFF file?

This is probably due to a different interpretation of how an OFF should be written. Geomview indexes vertices starting at zero, while some other programs are known to start at one. The following C program will convert a plain one-indexed OFF to a zero-indexed OFF.
#include "stdio.h"
int main(void) {
    char s[256];
    int v, f, i, n, t;
    gets(s);
    if (strcmp(s, "OFF")) {
	fprintf(stderr, "not an OFF\n"); 
	exit(1);
    }
    puts(s); gets(s); puts(s);
    sscanf(s, "%d %d %d", &v, &f, &i);
    for (i=0; i!=v; ) {
	gets(s); 
	if (strlen(s)) {
	    puts(s); i++;
	}
    }
    for (i=0; i!=f; i++) {
	scanf("%d", &n);
	printf("\n%d", n);
	for (v=0; v!=n; v++) {
	    scanf("%d", &t);
	    printf(" %d", t-1);
	}
    }
    printf("\n");
    return 0;
}


How can I animate a sequence of Geomview/OOGL files?

You might try using Animator, an external module that is distributed with all versions of Geomview. With Animator, you can tell Geomview to read in a sequence of OOGL files and then play through this sequence forwards, backwards and also in single frame steps using the VCR like interface.

To use Animator click on the Animator entry in Geomview's External Modules browser. If it does not appear in the browser, then Geomview has probably not been installed properly. For more information about Animator read the info panel available through the program or the the man page (by typing man animate).


Output


How can I save a sequnce of snapshot files or create a video animation (MPEG/QuickTime/animated GIF)?

There are several variants of this question:
  • > I would like to save a sequence of ppm snapshot files of a single
    > off object while it is rotating so that I can convert the sequence
    > into a movie. The only method I know of is to rotate the object
    > slightly with the mouse, stop the motion, and save each frame
    > individually. Is there a faster more automatic method, such as a
    > command script. If so, do you have a sample command script that I
    > could modify?
    

    Two options:

    • If the motion is axis-aligned, it's pretty easy to use the rotate and snapshot GCL commands together:
      (snapshot targetcam /tmp/foo%03d.rgb)
      (transform world world world rotate .1 0 0)
      (snapshot targetcam /tmp/foo%03d.rgb)
      (transform world world world rotate .1 0 0)
      
      and so on. The snapshot commanad auto-increments the filename.

    • But for a more complex motion than the simple rotation around the x axis that I have above, consider using StageTools, which is a suite of tools designed to help people easily make animations from Geomview. StageTools is included as a module in recent versions, but if you need to download it is available at http://www.geom.uiuc.edu/software/StageTools/

  • > I have used Geomview to view movies with the animation tool. How can
    > I convert that movie to another animated format (e.g. an animated
    > GIF) so that I can put it on display in a web page, viewable by
    > someone without Geomview?
    

    It's true that StageTools will do this and much more too. But there's also a very easy way to do this directly inside the Animate module: the Command function will run an arbitrary GCL command after each frame. So to automatically take snapshots at each frame, you'd hit the Command button and type something like
    (snapshot c0 /tmp/foo%03d.rgb)
    into the text field. Then when you hit play you'll see that it's now jerky since it's saving an image off to disk each time. You might want to turn on the "Once" radio button so that it stops after running through each frame once. Then you can use your program of choice to create an animated gif or quicktime movie from this bunch of image files. For instance, on the SGIs you could do this with "mediaconvert".


How can I save a picture of exactly what I see in a camera window?

Make sure that the camera window you want is the active one, then select the "Save" item of the "File" menu on the main panel (or use the ">" hotkey). In the panel that appears, there is a choice box that is set to Command by default. Select one of the snapshot options, enter the filename in the Selection input, and click "OK".

In the SGI version, you have three image snapshot choices: SGI screen, PPM screen, and PPM software. Both the screen choices literally save the onscreen pixels into a file, in either SGI (aka RGB) or PPM format. The PPM software choice will rerender the image into an offscreen buffer using the software renderer from the vanilla X version of Geomview. Thus, it might not be pixel by pixel identical to what you see.

In the X11 version, you have only the PPM choices.


How can I make a true PostScript file that looks good at multiple resolutions instead of just converting a bitmap into PostScript?

Make sure that the camera window you want is the active one, then select the "Save" item of the "File" menu on the main panel (or use the ">" hotkey). In the panel that appears, there is a choice box that is set to Command by default. Select the PostScript snapshot option, enter the filename in the Selection input, and click "OK".

This method has advantages and disadvantages, compared to saving an image bitmap. The advantage is that the result is resolution independent -- you can print it on a high resolution printer and not see any jagged edges. The disadvantages are that our PostScript renderer can't do smooth shading and uses the painter's algorithm for hidden surface removal. The latter means that intersecting objects and some other ill-conditioned scenes will be drawn incorrectly, or even that closer objects will be drawn behind faraway objects. It often works, but not always.


Why does my PostScript snapshot look wrong?

See previous answer.


How can I make a high quality image with RenderMan?

If you have Photorealistic Renderman (a commercial product of Pixar), or BMRT (Blue Moon Rendering Toolkit, a public domain implementation), you can create high quality images with transparency and more accurate lighting in the SGI and X11 versions. To do this, bring up the Save panel and select "RMan [->tiff]" from the save options. Enter a filename and click "Ok". Bring up a shell window and change directory to where you saved the file. Type "render filename" (where filename is the name you saved as). When this finishes, you will have an high quality image in "filename.tiff". To create a higher resolution image (to reduce jagged edges), edit the file you saved. There will be a line about fifteen lines down from the top that begins with "Format", i.e. "Format 450 450 1". The first two numbers are the resolution of the created image. Change these to what you like (you should keep the ratio of the numbers the same to avoid distortion), then render the file again.

X Specific Questions


How do I speed up the X11 version?

See the discussion of rendering options in the next question.


What do the Z-Buffer and Dithering controls in the Cameras panel do?

These control allow you to change how the X11 version renders objects. The dithering checkbox, which only appears when running on an eight bit display, allows you to turn dithering on and off. Dithering is the method by which Geomview uses a small set of colors (less than 217) to show any color you request. This is done by placing pixels of slightly different color next to each other and letting your eye blend them together. Unfortunately, it takes a fair bit of computing to do this. Turning it dithering off will speed up rendering, but colors used won't be exactly what you want. Depending upon your scene, this may be an acceptable tradeoff.

The Z-Buffer popup menu allows you to select between three different methods of hidden line/surface removal: z-buffering, depth sort, and none. Z-buffering is the most accurate and enables the near and far clipping planes. Depth sort uses less computing, but will be inaccurate if objects intersect (polygons will pop in front when they should be partially obscured) and in certain other circumstances (long, narrow polygons close to other polygons are one example). Depending on your scene, using this method could look just the same as z-buffering but be much faster. The "None" option turns off all hidden line/surface removal. This is only recommended for a scene which consists of just lines in one color.


What does "Not enough colors available. Using private colormap" mean?

This happens when using the X11 version on an eight bit display (currently common on workstations). An eight bit display can only show 256 colors simultaneously. These colors are shared by all the programs running. Once a colorcell has been allocated by an application, its color is fixed. Geomview tries to grab many colors when it starts. If it fails to get them, it prints this message and uses a private colormap. A private colormap means that Geomview now has access to all 256 colorcells. Unfortunately, these colors will only be displayed when the cursor is inside one of Geomview's windows. The switching of colormaps when the cursor enters and leaves the windows will give a technicolor look to the rest of the display.

If you don't like the technicolor effect, you will have to quit the programs which are using up colormap space. Examples of programs which use lots of colormap space are background pictures, image viewers, visualization software, and WWW browsers.


What does "Shared memory unavailable, using fallback display method" mean?

The X11 version of Geomview uses the shared memory extension to move images quickly between the program and the X server. However, this method of communicating with the X server only works when running Geomview on the same machine as the display. If Geomview can't use shared memory, it prints this message and goes back to using standard X calls. Everything will work the same, it will just run much slower, especially if you're running over the network.


Why do I get compiler errors about including files Xm/*.h?

You're trying to compile the X11 version and the compiler can't find the Motif header files. If you have Motif but the headers are in a nonstandard place, change the "SYSCOPTS" in your makefiles/mk.${MACHTYPE} file. If you don't have Motif, you won't be able to compile Geomview. In this case, use one of the binary distributions, if you can.
 
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