
84 II Buildable Tools
Original
Categorization
Inside Touching
Aligned
Touching
Inversed
Outside
After “not”
Operation
Outside Touching
Inversed
Touching
Aligned
Inside
Table 8 .2. Logical “not” operation.
8.2.2 CSG Operations
Table 8.1 describes the most common CSG operations and the ones implemented by
our algorithm. It is helpful to think of CSG operations in terms of Boolean algebra
on sets, specifically sets of points in a 3D volume. By extension, our algorithm
performs these logical operations on sets of categorized geometry. In a similar way,
the CSG tree can be thought of as analogous to a logical expression tree, and similar
transformations ...