As long as I can find a point, I can create dimensions. But what about something like a pyramid where I would need to find an invisible point at the center of the base, then go to the peak, and then pull out the measurement so it is outside the geometry of the object?
For something like your pyramid, you don’t need to dimension to the center of the bottom. Just dimension to the center of the edge.
If you do need to dimension to an unmarked point, you can place a couple of crossing guidelines to create an intersection or you can add a guidepoint or draw some small line segments.