I began using perspective drawing in my paintings in 1963, and because perspective was not really taught at the San Francisco Art Institute, I taught my self the discipline from books and by trial and error. I began working on a Apple II computer with GRAFORTH in 1982. I have since done a number of computer aided paintings, doing 3-D renderings (or sketches) and projecting them onto a canvas as a guide to a finished painting. Since 1987 I have been using VIDI's Presenter 3D, a software package for 3-dimensional modeling, rendering and animation on the Apple Macintosh. It's a wonderful software product, and has greatly expanded the possibilities of my art. It is a shame that this small company has gone out of business. I still use it once in a while, and a FREE working version of this venerable 3-D modeling, rendering, and animation program can be snagged at VIDI.com. I am now attempting to learn form*z and Cinema 4D, two excellent advanced software programs.

. . . Ron Davis

Since 1964 when I began including pictorial space into my paintings I have done thousands of cubes, slabs, blocks, etc. Modeling and rendering a cube is a simple task, even simple minded, but as an artist that is what I do, and have done over and over in my pre-computer perspective drafting and in VIDI since 1987. Drawing a 3D cube using the computer is a lot easier than drawing it the old fashioned way. One of the simplest things to do using Presenter 3D is draw a white cube [using a Primitive] and render it. This view uses a virtual forty-five degree wide-angle lens.

The cube's color is changed from white to red. The cube is placed on a bit-mapped textured rug on a black floor, balanced on its edge, and lit with two suns, thereby creating two cast shadows.

But if one wants not a shaded white or red cube, but rather wants to "Paint" a cube with a red-orange top and bottom, green front and back, and red sides, ones modeling strategies must change a bit. The white cube was lit by changing two white light source suns to green and red lights, thereby painting the cube with colored light. Of course the hidden sides of the cube are still white (or shadowed gray), but we don't know that, and assume that they are colored. The cast shadow of the green light is red, because in the shadow there has an absence of green light, and the shadow of the red light is green. Mixing the red and green light sources gives the unshadowed rug areas a yellow-brown cast.

In this simple minded endless animation the white cube changes to a red cube then back to a white cube and the the red and green suns turn to white suns and back to red and green while the cube does one rotation. At the same time the black floor under the grey rug turns turquoise and back to black.

Next, the Cube is placed in a virtual room with a marble tiled floor. The suns are replaced with "point lights" and a soft "spot" light is used to flood the walls with white light. The Cube is given a Transparent Glass property including the light bouncing refraction as well as reflectivity.