Rasterize voxels

First I would like to point out the context in which I face this development.

Find and develop a language to learn to program ColorForth. I am accidentally a developer of a programming language.

I am always interested in the development of graphic technology and as a way to advance the language I began to incorporate everything necessary for a 3D graphics engine.

But, for a matter of language, the idea is to try to build without using libraries or, rather, creating libraries in the language itself.

Another condition is to use integers for all calculations. From this I begin my development.

In short, it is intended to write directly in the framebuffer only with integers using my programming language,: r4 and now the successor, r3. Here I ask for a consensus because my interest is in the algorithms, anyone can implement these ideas in the language they want.

At this moment I have solved many parts of the 3d graphics engine, and I also have many unresolved places, I found an interesting algorithm to rasterize voxels in an isometric perspective and I want to explain the way of operation. This is the main purpose of this blog.

This is the programming language and its successor

https://github.com/phreda4/reda4

https://github.com/phreda4/r3d4

This is the algorithm that I will try to explain

https://github.com/phreda4/r3d4/blob/master/r3/dev/cuboiso5.r3