Do you mean the internal structure of standard bricks like 3001 (Brick 2x4)?
Yes, that's usually omitted, though the LDraw 3001 matches the older mould from the 1970s.
Not sure if that helps your project, but a Quick-and-Dirty workaround would be that you could try replacing your local copy of p/stud.dat (the file containing the standard stud geometry) with one that "sort of" does. Since you can't have it extruded correctly inwards due to collision (maybe it even works in your case, not sure) you would need to create a very thin cylinder extruded outwards to trick your algorithm/AI into seeing the shadows of those cavities.
Yes, that's usually omitted, though the LDraw 3001 matches the older mould from the 1970s.
Not sure if that helps your project, but a Quick-and-Dirty workaround would be that you could try replacing your local copy of p/stud.dat (the file containing the standard stud geometry) with one that "sort of" does. Since you can't have it extruded correctly inwards due to collision (maybe it even works in your case, not sure) you would need to create a very thin cylinder extruded outwards to trick your algorithm/AI into seeing the shadows of those cavities.