PovRay for scientific illustration: diagrams to photorealism

The following is a short illustration of how PovRay (a free and powerful rendering engine) can be used to create images suitable for all stages of scientific research: investigation, diagrams for papers, and high quality images for promotional purposes. The three versions below are all described identically with regard to their geometry, the differences are only in how that geometry is rendered. Note the PovRay files provided here are only intended to illustrate the rendering modes, there are external (#included) files and textures not included.

This is the diagram as it appeared in the journal, almost all features of PovRay are turned off, it is flat shaded, one light source at the camera position, no shadows, and the camera employs an orthographic projection. This is in the style typical of scientific or mathematical illustration.

Self-organization of synapses to form local maps. Left: polar plane representation of activity in an efferent field. Angles 0-2pi are represented by the colors of the spectrum, repeated twice. Middle: input map; saturation of synapses projected to the afferent field forms a Mobius projection from the efferent field. Distance relations are preserved, but angular relations are doubled to 0-4pi. Right: local map; synapses within the afferent field become saturated so as to form an intertwined mesh of bi-directional connections, closed over 0-4pi. [Figure legend from J.J. Wright et al. / Vision Research 46 (2006) 2703-2720]

Figure 2 [figure2.pov]

This is similar to the renderings of the geometry that were created during the scientific visualisation process. This is exactly the same geometry as in figure 1 above, the only difference is the rendering style, surface properties, lighting, and the placement of the components. Images of this form were used to solidify concepts in geometry and for discussion between researchers.

Figure 3 [figure3.pov]

The following was created as a presentation form of the same geometry. It is rendered using radiosity (MegaPov), the lighting is defined by a HDR lighting environment of the staff tearoom (there are no other light sources). Additionally the result of the rendering was saved as a HDR image file (Radiance format) allowing exposure changes and filtering to be applied in post production without the usual artifacts that one encounters whn using a limited 8 bits per r,g,b colour space. The page in the scene is how the diagram in figure 1 appeared in the draft version of the published paper. The final image was rendered at 6400 x 4800 pixels for a high resolution photographic print.

Rapid prototype model