History of ProBuilder
ProBuilder was originally one of three tools offered by ProCore in the Asset Store. The other two were called ProGrids and PolyBrush. Unity bought either the company or the three tools, I'm not sure which. Since then, the functionality of ProGrids has largely been absorbed into Unity's Grid and Snap system, which we explored in Chapter 7, Prep Work: Materials, Grids, and Snapping. ProBrush is a terrain- and level-painting/populating tool. It is available from the Package Manager under the Unity Registry tab. Here's how to start using ProBuilder.