Re: [Visualpython-users] Is frame "pickable" ?

[Haibo Z. <ha...@gm...>]

Hi Bruce,

One more small change might be needed:

        if hasattr(pick,"frame") and pick.frame:
            pick = pick.frame

hasattr(pick,"frame") needs to be added, otherwise it will throw an
exception "AttributeError: 'NoneType' object has no attribute 'frame'" when
I drag on the blank area.

Thank you for your help

Regards,
Haibo

On Fri, Jun 19, 2009 at 1:25 PM, Bruce Sherwood <Bru...@nc...>wrote:

> The following slight modification works. When you pick an object, just
> check to see whether it is in a frame, and make the frame picked:
>
> from visual import *
> scene.range = 5 # fixed size, no autoscaling
> ball = sphere(pos=(-3,0,0), color=color.cyan)
> cube = box(pos=(+3,0,0), size=(2,2,2), color=color.red)
>
> f = frame()
> cylinder(frame=f, pos=(0,0,0), radius=0.1, length=1,
>         color=color.cyan)
> sphere(frame=f, pos=(1,0,0), radius=0.2, color=color.red)
> f.axis = (0,1,0) # change orientation of both objects
> f.pos = (-1,0,0) # change position of both objects
>
> pick = None # no object picked out of the scene yet
> while 1:
>  if scene.mouse.events:
>     m1 = scene.mouse.getevent() # get event
>     if m1.drag:
>         drag_pos = m1.pickpos # where on the ball
>         pick = m1.pick # pick now true (not None)
>         if pick.frame:
>             pick = pick.frame
>     elif m1.drop: # released at end of drag
>         pick = None # end dragging (None is false)
>  if pick:
>     # project onto xy plane, even if scene rotated:
>     new_pos = scene.mouse.project(normal=(0,0,1))
>     if new_pos != drag_pos: # if mouse has moved
>         # offset for where the ball was clicked:
>         pick.pos += new_pos - drag_pos
>         drag_pos = new_pos # update drag position
>
> Bruce Sherwood
>
>
> Haibo Zhao wrote:
>
>> Hi guys,
>>
>> Say I have a sphere and a cylinder, and I grouped them together in a
>> frame. And then I tried to drag this frame using the code on this page
>> (With small changes). So basically, I want all the objects in the
>> frame move together when I drag the frame.
>>
>> http://vpython.org/contents/docs/visual/mouse_drag.html
>>
>> It seems like frame is not "pickable"?
>>
>> Any input will be appreciated.
>>
>> Thanks,
>> Haibo
>>
>>
>> Below is the code:
>>
>> from visual import *
>> scene.range = 5 # fixed size, no autoscaling
>> ball = sphere(pos=(-3,0,0), color=color.cyan)
>> cube = box(pos=(+3,0,0), size=(2,2,2), color=color.red)
>>
>> f = frame()
>> cylinder(frame=f, pos=(0,0,0), radius=0.1, length=1,
>>          color=color.cyan)
>> sphere(frame=f, pos=(1,0,0), radius=0.2, color=color.red)
>> f.axis = (0,1,0) # change orientation of both objects
>> f.pos = (-1,0,0) # change position of both objects
>>
>> pick = None # no object picked out of the scene yet
>> while 1:
>>  if scene.mouse.events:
>>      m1 = scene.mouse.getevent() # get event
>>      if m1.drag:
>>          drag_pos = m1.pickpos # where on the ball
>>          pick = m1.pick # pick now true (not None)
>>      elif m1.drop: # released at end of drag
>>          pick = None # end dragging (None is false)
>>  if pick:
>>      # project onto xy plane, even if scene rotated:
>>      new_pos = scene.mouse.project(normal=(0,
>> 0,1))
>>      if new_pos != drag_pos: # if mouse has moved
>>          # offset for where the ball was clicked:
>>          pick.pos += new_pos - drag_pos
>>          drag_pos = new_pos # update drag position
>>
>