add light source

[vosmer]

There have to be light source feature to visualize 3d shapes. You cant get the sphere is the sphere if no light makes no shadow on the surface... and so on

[different55]

As a workaround, you could probably split a lot of the shapes up into shaded halves. Like, for a sphere, draw two hemispheres and have them match the rotation of your light source. Or for a cube, calculate for each side if it's facing toward or away from the light and swap colors based on that.

Doesn't work for everything, but that's because shading's kinda going against the grain of how Zdog works.