Double bounding box

voljanko

Hello.
I have a problem to get the coordinates of the rotated bonding box corner.
On the screen is different bounding box than what I get with group.bounds.corner[0] (this is why "double bounding box" tittle). You can see it on the picture.
I have tried to apply the transformation of the group to the corner point,but the result is not right.

I want to have the coordinates of the corner of the bounding box that is on the screen,so x or y should be 0.

thomthom

Have a snoop around in my plugin that converts the bounding box into edges: http://forums.sketchucation.com/viewtopic.php?t=29377

voljanko

Thanks,but I don't need the real bbox.I just need to retrieve the coordinate of one of the corners of the bbox on the picture.
It should be (-0.707 , 0 , 0) or (0 , -0.707 , 0) .

thomthom

So you have the point - but want to move the group so that the point is located at 0,0,0?

<span class="syntaxdefault"><br />tr </span><span class="syntaxkeyword">=</span><span class="syntaxdefault"> Geom</span><span class="syntaxkeyword">;;</span><span class="syntaxdefault">Transformation</span><span class="syntaxkeyword">.new(</span><span class="syntaxdefault"> point</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">vector_to</span><span class="syntaxkeyword">(</span><span class="syntaxdefault"> ORIGIN </span><span class="syntaxkeyword">)</span><span class="syntaxdefault"> </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault">group</span><span class="syntaxkeyword">.</span><span class="syntaxdefault">transform</span><span class="syntaxkeyword">!(</span><span class="syntaxdefault"> tr </span><span class="syntaxkeyword">)<br /></span><span class="syntaxdefault"> </span>

voljanko

No,I will explain more:
I have rotated the group for 45 degrees.
If I call the group.bounds.corner(0) ,I get the point of the axis aligned bbox (green circle on the picture).
Instead,I want to have the coordinates of the bbox on the screen ,witch is NOT axis aligned(red circle on the picture).

thomthom

Right - this is where you can look at the plugin I linked to where you can see how I obtain the co-ordinates of the boundingbox.

voljanko

Ok,I have check your plugin and find the line

       pts = self.bound_points(bb).map { |pt| pt.transform( entity.transformation ) }

interesting.But I have already try to put the transformation to my point,but the result is wrong:

cube=Sketchup.active_model.selection[0]
point=cube.bounds.corner(0)
point.transform!(cube.transformation)
UI.messagebox point.to_s

The result that I get is wrong (-0,-1.707,0).
As you can see on the picture it should be (-0,-0.707,0).
What em I doing wrong?

voljanko

Ok,I got it.
The mistake was that I was taking the bbox of the group,but should take a bbox of the definition of the group,like in your plugin.
But why didn't you told me to look in your plugin?

Dan Rathbun

@voljanko said:

I have rotated the group for 45 degrees.
If I call the group.bounds.corner(0), I get the point of the axis aligned bbox (green circle on the picture).

Instead, I want to have the coordinates of the bbox on the screen, which is NOT axis aligned (red circle on the picture).

group.local_bounds()

voljanko

@dan rathbun said:

group.local_bounds()

Yes,it is working,I have test it....BUT,it is only available for groups,not components.

Dan Rathbun

@voljanko said:

@dan rathbun said:

group.local_bounds()

Yes,it is working,I have test it....BUT,it is only available for groups,not components.

This is because .definition() is exposed to ComponentInstance objects, so:

def get_local_bounds(obj)
  case obj
  when Sketchup;;Group
    obj.local_bounds()
  when Sketchup;;ComponentInstance
    obj.definition.bounds()
  else
    obj.bounds()
  end
end