HiddenLineDrawing - Functionality

Hi @GregArden,

first thank you for HiddenLineDrawing! Its a great addition to V6 - worth the update!
I have some questions / suggestions and start this new topic, since you’ve closed the initial thread.

Is a way to get the result of the calculation as non-transformed curves?
(Edit: Right now I get it with the inverse transformation of the non-flattened result.
If I’m not missing something then there should be a parameter Transform = False?)


Thanks for your feedback on the HiddenLineDrawing functions in RhinoCommon. I’m excited that people are discovering this and tying it out. Right now we are categorizing feedback into the following classes

  1. Fixing bugs - cases where it doesn’t do what it is designed to do.
  2. Explaining and documenting what’s there now so users can find it and try it out.
  3. Making the programming interfaces, (c++, RhinoCommon, and Grasshopper) interfaces easier and more intuitive to developers.
  4. Add future functionality

Sounds like you have figured out how to get the HiddenLineDrawing results in 3d world coordinates,
but you think there should be an option on HiddenLineDrawingParameters to produce HiddenLineObjectCurves in world coorfinates instead of HLD_coordinates.

Greg Arden
Rhino Development

Correct! Background is that I’m working on a tool to support laser projections with multiple projectors. And of course not all projection geometry (curves) can be seen by all projectors due to “shading effects” of some other geometry (solids). The non-transformed curves is what I need, to distribute the geometry to the available projectors.

And another one for point 4. Future Functionality:
For the described scenario I do not need to calculate the HiddenLineDrawing of ALL geometry. I’m only interested in a few curves of the whole scene (projection geometry). But of course I’ll have to define the geometry (breps and meshes) hiding these curves.

One way would be to use all visible geometry but only calculate the HiddenLineDrawing for the selected geometry.

Let me know if my non-native explanations are not clear!

Many thanks, Jess

P.S: I think we should use a separate thread for bugs.