[Plugin] Scaling cube from point down to Z=0

[SmithsOfUrth 0]

Hey guys!

 

I'm working on a plugin (for Cura 3.6+) to enable manual supports, and one of the features I want to add is to show some kind of "preview" of what area the support is going to be taking.

Right now, I'm creating a cube and adding it to a X,Y position using this code:
 

active_camera = self._controller.getScene().getActiveCamera()
picking_pass = PickingPass(active_camera.getViewportWidth(), active_camera.getViewportHeight())
picking_pass.render()

picked_position = picking_pass.getPickedPosition(event.x, event.y)

After that, the script creates a cube kinda manually (I'm basing myself on the SupportEraser plugin) with a value entered by the user. Thus, the cube has the same width, height and depth.
What I want to do is to make it as big in the Z axis as necessary so that it touches the build plate , and the user can see what it'd look like once it's processed.

Is there a way to scale it enough?

 

Thanks!

[nallath 1,123]

There are two things you can do; You can either create longer squares with the MeshBuilder and move them down a bit (since they are places based on their center) or you can scale the model (check the setScale function of the SceneNode that contains the meshdata)

[SmithsOfUrth 0]

Thanks for answering, nallath.

I ended up doing this to create a cube that touches the buildplate:

s = size / 2
dtb = distance_to_buildplate
verts = [ # 6 faces with 4 corners each
  [-s, -dtb,  s], [-s,  s,  s], [ s,  s,  s], [ s, -dtb,  s], # a = x-yz
  [-s,  s, -s], [-s, -dtb, -s], [ s, -dtb, -s], [ s,  s, -s], # b = x+yz
  [ s, -dtb, -s], [-s, -dtb, -s], [-s, -dtb,  s], [ s, -dtb,  s], # c = xy-z
  [-s,  s, -s], [ s,  s, -s], [ s,  s,  s], [-s,  s,  s], # d = xy+z 
  [-s, -dtb,  s], [-s, -dtb, -s], [-s,  s, -s], [-s,  s,  s], # e = +xyz
  [ s, -dtb, -s], [ s, -dtb,  s], [ s,  s,  s], [ s,  s, -s] # f = -xyz
]

where "distance_to_buildplate" is the position in the Y axis of the cube when you click on the model, which is the same thing as the distance from the cube the ground.