Making Stereo Images

Stereoscopic images can be rendered with a simple sequence of text commands, cycling between the left and right monoscopic stereo modes and exporting one scene for each eye:

        display stereo left
        render Tachyon left.dat
        display stereo right
        render Tachyon right.dat

External renderers don't always support the ability to draw stereo images. In principle, it is possible to write the scene to the file twice with the appropriate transformations applied to make the view correct for each eye, but then the shadows would be incorrect. Instead, we suggest making one image of the current scene, then shift the molecules to the left (or right) to make the other image. The text commands for this are something like:

        display stereo off
        render Raster3D left.r3d
        trans by -.1 0 0
        render Raster3D right.r3d

The two files must then be rendered to produce the rgb file. As it turns out, this method makes it easy to produce stereo images of ordinary Raster3D files. Since VMD can read the Raster3D format, all you have to do is read the file and then execute the commands listed above. The text commands for generating left or right views also have equivalents in the GUI under the Stereo option of the Display form.