LightAct supports both 2D and 3D projection mapping. Although there are many conceptual similarities, there are also some key differences between the two.
2D projection mapping refers to projecting content on flat surfaces such as screens and walls. It is mainly meant for simpler projects where a smaller number of projectors is required.
The 2D projection mapping approach allows you to finish the process without using any additional virtual objects in the Viewport, aside from a canvas and projectors. All you have to do is correctly assign the texture to each projector and do some warping & blending.
3D projection mapping is used for projecting content onto 3D objects. It is generally a go-to choice for more complex projects where depth and other spatial concerns need to be accounted for.
For successful 3D projection mapping, at least one 3D object is also required.
In the final phase, the chosen texture needs to be displayed directly on the virtual 3D object in LightAct. Only then will the texture be visible on the physical 3D object as well. For this type of projection mapping, apart from manual Warp & Blend, an automatic blending feature is available.