Gives the point of a region closest to a given point. For a solid Disk or Ball
RegionNearest[reg, p]
RegionNearest[reg]
RegionNearest[Disk[{0, 0}, 1], {3, 0}]
→ {1, 0}RegionNearest[Disk[{0, 0}, 2], {3, 4}]
→ {6/5, 8/5}RegionNearest[Rectangle[{0, 0}, {2, 2}], {3, 3}]
→ {2, 2}