Datoviz is much lighter and younger than VTK. It compiles in seconds, making it much faster to build, and it's easier to install and distribute.

It has far fewer features since it focuses solely on rendering common primitives. For example, it doesn't handle data file loading, except for a few quick loaders like OBJ used mainly for testing.

There's almost no computational geometry, data processing, or signal processing functionality. Datoviz is solely focused on interactive rendering.

Datoviz also supports fast, high-quality 2D vector graphics, scaling efficiently to millions of points. In contrast, VTK is primarily designed for more complex and heavy 3D rendering tasks.