Point selection and inferencing



There have been a number of posts about the limitations of the inference engine built into SU (wonderful as it is!). They often concern the difficulty of selecting the right point to lock to when there are several possible ones close together. Tracing over a line that is just off axis is a case in point. So here’s a suggestion to improve that.

When you want to draw a line (say) you click on the first point. To complete it, you would have two options:

  1. doing just as you do now with magnetic snapping as default; or,
  2. you right click before selecting the second point which would bring up a list of click points to choose from.

Click points might include:

  • end of line
  • centrepoint of circle
  • midpoint of line
  • midppoint between two points
  • intersection

It would be a very nice touch if only the options available came up in the list according to where the cursor is (to cut down on list length). You would then select the point type you want from the list and the inferencing would temporarily be limited to the relevant instances locally.

This could eliminate the need for extensions like SB Circle Intersect and Midpoint as well as making point selection generally easier.


Yeah I agree with the need for designating snap points.
Right clicking is one way to achieve this.
Another way that works well is to have a toggle button that cycles through the available snap points in the local area. This is what happens in Revit where you hit TAB repeatedly and the snap icon will change to the various points. It is good because it’s contextual and very visual.

One of Revit’s few positives. :slight_smile:


I am told by @slbaumgartner that no one outside the SU development team knows the code for the inference engine and so anything like this would have to be implemented as part of native SU, not as an extension.