You can start the program in the same way you would start volslice. Just type "volslice3d" followed by the situs file.

@: ./volslice3d 1_mt.situs 
.svtrc at /home/zdvex/zdv097/Source/SVT/apps/volslice3d not found!
Parameters set to default values!
volio> File 1_mt.situs - Header information: 
volio> Columns, rows, and sections: x=1-89, y=1-89, z=1-61
volio> 3D coordinates of first voxel (1,1,1): (0.000000,0.000000,0.000000)
volio> Voxel size in Angstrom: 6.000000 
volio> Reading density data... 
volio> Volumetric data read from file 1_mt.situs
volslice3d> Min. / max. density values:-32/49
volslice3d> creating xy slice:0
volslice3d> creating xy slice:1
volslice3d> creating xy slice:2
volslice3d> creating xy slice:3
volslice3d> creating xy slice:4
volslice3d> creating xy slice:5
volslice3d> creating xy slice:6
volslice3d> creating xy slice:7
volslice3d> creating xy slice:8
volslice3d> creating xy slice:9
...

The first warning message should show you, that you dont have a special configuration file for volslice3d. In this case volslice3d will use the built-in default configuration. See also the configuration section.

After the error message you can read a block of information concerning situs (all lines starting with "volio>"). You will know this text from the volslice tool. Please have a look at the situs documentation!

The lines beginning with "volslice3d>" will show you that volslice3d is creating the texture maps for the slices through the density map. This can take some time, but on a recent workstation it should just be a couple of seconds.

After all these you can see the main window and the gui window of volslice3d. You can rotate the scene be dragging the mouse in the main graphics window.

To manipulate the 3D view, volslice3d provides a small GUI window:

With the first three widgets you can move the three active slices through the density map. You can increase and decrease the number with the small arrow buttons or just type in a number and hit return.

With the color listbox you can specify the used color model. Volslice3D provides at the moment three different color models:

• Gray: Density values are mapped by linear interpolation to different levels of gray. The maximum density value (mxd) is represented white and the minimum density value (mnd) is represented black.
• RWB: The densities are mapped to a red-white-blue gradient. White corresponds to a density value of zero. Red corresponds to negative density values (color levels increase with absolute density value and are normalized by the maximum of -mnd, mxd).
• RYG: The densities are mapped to a red-yellow-green gradient (linear interpolation from mnd to mxd).

The user can specify a cutoff-value. All density values less than this value are not visible (actually they are transparent).

When you change the color model or the cutoff value volslice3d needs to recalculate all the texture maps for the slices. You can start this process with the "Apply" button. After the recalculation the colormodel and cutoff-value changes will become visible!

You can display all slices at the same time. This is a good way to get an impression of the volume, but you must select the cutoff values carefully. When you select a low cutoff value most of the slices will be opaque and you can only see the first slice masking all other slices. And you must be careful when you rotate the scene. It is possible that you will see nearly nothing, because you are looking at the edges of the slices.

Displaying all slices at the same time is a very time consuming job for the graphics hardware of your workstation. The computer will perhaps react only slowly after switching on all slices. Therefore you can switch on and off the "block-mode" of the slices seperatly for each dimension (by switching on and off the checkboxes "Block XY", "Block XZ" and "Block ZY").

You can configure Volslice3D with a configuration file called ".svtrc". A short example of such a file:

Fullscreen = FALSE
WindowPosX = 100
WindowPosY = 130
WindowWidth = 800
WindowHeight = 400

With this config file volslice3d will start as an application in a window. The window will have a size of 800x400 pixels and will appear on the position 100,130.

When you change the first line in the config file from "Fullscreen = FALSE" to "Fullscreen = TRUE", volslice3d will start as a fullscreen application and you will be not able to see any other application (until you will close volslice3d by pressing the "quit" button). It is better to start volslice3d in fullscreen mode when you are using stereo shutter glasses, because there will be no disturbing window frame.

There are some other things you can configure with the .svtrc file. There is a table following, showing all possible keywords, the expected type of the value and the default value (volslice3d will use the default values if it cannot find the keyword in the .svtrc file).