Design Nomenclature / Digital Model Making
Texture Painting
Also called 3D painting, surface painting, projection painting
Painting colour and material straight onto a model's surface, projected through its UVs or into a volume, rather than into a flat image that must then be mapped. The seams and the stretch are still underneath: painting in 3D hides them from the painter, not from the renderer.
In practice
The real shift is that modern tools paint every channel at once — albedo, roughness, metalness, height — not that the viewport is 3D. Painting a highlight into albedo remains the oldest mistake in the trade, and a 3D viewport makes it easier to commit, not harder.