February 5, 2019
Grayboxing in Unreal Engine
Basics of BSP
Wiki Unreal Engine – Basic Level Design BSP
I’ve started to learn the basics of the Unreal Engine (UE4), primarily with respect to it’s BSP (Binary Space Partitioning) and grayboxing levels. It’s the engine of choice for our Architectural Approaches to Level Design class specifically for this purpose.
Brushes
Unreal provides a base of shapes to work with that are perfect for setting up the overall shape and scale of a level or world in 3D. There are boxes, cones, stairs (linear, curved, and spiral), cylinders, and spheres. These shapes however also have various parameters associated with them that really help you mold out your world. The objects can have their sizes changed without strange scaling effects that need to be accounted for. The stairs have parameters for stair size and shape.
One particularly useful feature is that these shape brushes can be either additive or subtractive. Additive does what you would expect, creates the shape in the world. Subtractive however removes the colliding volume from any existing additive shape it intersects with. This can quickly and easily create some interesting shapes, or help build out rooms and doorways. Speaking of rooms, another helpful feature for this is that you can make some of these shape brushes hollow. This leaves a thin shell of the shape with a completely empty volume.
Geometry Mode
Finally, if you really want to stretch the creativity of your shapes, you can further edit them in Geometry Mode. This tool reminds me of Maya; it lets you do things like extrude faces or move around/remove vertices. This mode lets you craft the shapes almost anyway imaginable and is very easy to use.