[solved] rotating enitity toward target point

tbd

can anyone help me in implementing a rotation around group center to face toward a target point ?

EDIT:
here is the solution code:


def create_geometry(obj_origin)
  light = Sketchup.active_model.entities.add_group 
  light.entities.add_circle(ORIGIN,Z_AXIS,10.cm,3)
  light.entities.add_line(ORIGIN,ORIGIN.offset(Z_AXIS,10.cm))
  
  t1 = Geom;;Transformation.translation(obj_origin - ORIGIN)
  Sketchup.active_model.entities.transform_entities(t1, light)

  # return light group
  light
end

def rotate_geometry(grp, target)
  # quick access variables
  o = grp.bounds.center
  td = o - target
  axr = Z_AXIS * td
  anr = Z_AXIS.angle_between(td)

  # face the group toward this point
  Sketchup.active_model.entities.add_cpoint(target)
    
  t1 = Geom;;Transformation.rotation(o, axr, anr)
  grp.transform!(t1)  
end

grp = create_geometry(Geom;;Point3d.new(10,10,10))
rotate_geometry(grp,Geom;;Point3d.new(20,20,20))

Jim

To get the axis of rotation, take the cross product between the current direction (Vector) and the target direction(Vector).

To get the angle of rotation, use the API method angle_between for the current and target vectors.

Create a new rotation transformation and apply it.

tbd

thanks Jim. just before your response I solved it in another way, using the axes of the target direction and creating a transformation array.

wish I had asked this question 3 days ago