Please note: This tutorial was originally written for 3D Canvas 7. It has not been fully updated to reflect the changes made in 3D Canvas 8. An updated version will be made available in a future version of 3D Canvas 8.

Raytracing with POV-Ray

3D Canvas scenes are normally rendered using the Direct3D rendering engine. Direct3D with hardware acceleration is very fast. This allows you to design a scene in real time seeing the changes as you make them. This speed comes with some sacrifices though; Shadows are simulated and there are no reflections.

The image that follows shows a teapot rendered with the Direct3D rendering engine. Notice that the teapot appears to be shiny yet it does not reflect any of its surroundings.

The next image shows the same scene rendered with the POV-Ray raytracing engine. POV-Ray is a raytracing rendering engine that is available for free at www.povray.org. Notice that the teapot is reflected on the surface on which it sits and the teapot itself reflects its surroundings.

Unfortunately, these shadows and reflections come at a cost. While it took only a fraction of a second to render the image with Direct3D, it took more than a minute to render the image with POV-Ray.

3D Canvas support file exports to POV-Ray format. This allows you to export your scene to POV-Ray format and use the POV-Ray program to render the image.

3D Canvas Pro supports seamless rendering with the POV-Ray rendering engine. The standard Snapshot and Animation Recording Options provide a Raytrace option that if selected will result in 3D Canvas Pro automatically using the POV-Ray rendering engine to render your Snapshot or Animation. Note that this option is not available with the standard version of 3D Canvas.

Lighting

The lighting scheme for POV-Ray is slightly different than that of Direct3D so you may find that the final image produced by POV-Ray is somewhat darker, or brighter than the Direct3D produced image. The only way to correct lighting problems with raytracing is through trial and error. Rendering test images in low resolution and without anti-aliasing speeds up the POV-Ray rendering tremendously.

Images tend to look better in POV-Ray if the amount of ambient light is low. This is also true of Direct3D rendered scenes, but it seems to make more of a difference in POV-Ray rendered scenes.

Limitations

3D Canvas is primarily a Direct3D Modeling and Animation program. Some of the features of Direct3D have no equivalent in POV-Ray, and many POV-Ray features have no equivalent in Direct3D.