[IGSTK-Users] Code broken in CVS?

[Patrick Cheng]

Hi Anka,

I made a few changes to the example application.
Please check out the cvs code and give it a try.

Below is a brief description of the problem:

Problem: Objects do not show up in the window. Camera unable to find its 
focus

Cause: This is because of the single thread limit. Tracker hasn't got a 
chance to update TrackerTool until the
igstk::PulseGenerator::CheckTimeouts(); get called in the main loop.

If we setup the scene graph connection as:
object --> tool -x-> tracker <-- View
View can not reach object thus unable to adjust it's focus when 
ResetCamera is called.

Solution: Attach the object to the Tracker instead of TrackerTool at 
startup. Switch to TrackerTool after tracking started.

Results: You should see the ellipsoid and cylinder in the window 
(constant) at startup.
After tracking start, you should see them following your mouse position.
When stop tracking, they will disappear.

Thank you for your support for IGSTK!

Patrick


Anka Kochanowska wrote:
> Hi!
> Thanks for the clarification.
> I did not think of it this way. Usually tracking application show 
> something on start, but you are right - there is no reference, so 
> nothing to show. There is a call to reset camera in the example, and I 
> sometimes zoom and zoom and zoom and see nothing, although I know that 
> my pointer must be visible.
> 
> Thanks again
> Anka:-)
> 
> Andinet Enquobahrie wrote:
>> Anka-
>>
>>> Since there are no changes in the example code, something in IGSTK 
>>> must have been changed to cause the problems.
>>>
>>> So for now, I shall try to work with the release 3.0 again, hoping 
>>> for a fix in CVS.
>>>
>> You are better off sticking working with cvs version. Because, there 
>> were several other bug fixes....
>>
>> I just took a quick look at it your report and here are my comments
>>
>> 1) When you start the example application,  you "should NOT see" the 
>> cylinder and ellipsoid with the tracking turned off.  When tracking
>> is turned off, it means there is no tracking information which implies 
>> the transforms of the spatial objects are "expired" or
>> are invalid time stamps. So, what you are currently observing in the 
>> cvs version is the correct behavior.
>>
>> The behavior in  release 3.0 was wrong.  The spatial objects show up 
>> upon start EVEN without tracking information.
>> 2) When you turn on tracking, although you will get valid transforms 
>> and renderings of the cylinder and ellipsoid spatial objects,
>> you will not see the renderings since the camera is way out of focus. 
>> If you zoom out repeatedly using the right mouse button,
>> you will see the spatial objects. We might need to add a camera reset 
>> call to bring the renderings to the the widgets field of view.
>>
>>
>> Hope that helps
>> -Andinet
>>
>>
>>
>>>
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>>>
>>
>>
> 
>