Zdog is a 3D JavaScript engine for <canvas> and SVG. With Zdog, you can design and render simple 3D models on the Web. Zdog is a pseudo-3D engine. Its geometries exist in 3D space, but are rendered as flat shapes.
Zdog uses the same principle. It renders all shapes using the 2D drawing APIs in either <canvas> or <svg>. Spheres are actually dots. Toruses are actually circles. Capsules are actually thick lines. It’s a simple, but effective trick. The underlying 3D math comes from Rotating 3D Shapes by Peter Collingridge.