[IGSTK-Users] Flickering Spatial Object

[Andrew Wiles]

Hello,

I have set up an application similar to the Navigator example using the Aurora with two 6D tools.  However, when I attach the TrackerTool to a spatial object (using RequestSetParentAndTransform) the spatial object flickers in the view window.  

I have two tools attached to the Aurora, a tool under test and a reference.  The spatial object for the reference appears in the view window and does not flicker but the tool under test comes and goes from the view.  In fact, it doesn't appear more often than it appears.  I can move the tool under test around and the transformation of the spatial object updates successfully when it does appear.  I am also writing the transforms for both tools to the GUI screen and I obtain what appears to be 40Hz of data.  I connect the spatial objects (m_TestPlugTool and m_RefPlugTool) to the TrackerTools (m_TestTool and m_RefTool) using:

    igstk::Transform transform;
    transform.SetToIdentity(igstk::TimeStamp::GetLongestPossibleTime());
    this->m_TestPlugTool->RequestDetachFromParent();
    this->m_RefPlugTool->RequestDetachFromParent();
    this->m_TestPlugTool->RequestSetTransformAndParent(transform, m_TestTool);
    this->m_RefPlugTool->RequestSetTransformAndParent(transform, m_RefTool);

Does the validity time on the transform have anything to do with this?  I am using Qt and have played with the QtTest::wait (equivalent to FL::wait) function values in the main loop to see if that had any effect, but it only made visibility worse.  I have also played with the refresh rate of the view window, but that doesn't help either.

Does anyone have any suggestions for fixing this?  Google has not revealed any obvious answers.

Cheers.
Andrew

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Andrew D. Wiles, PhD, PEng
Research Scientist, Medical Division
NDI
103 Randall Drive
Waterloo, ON, Canada, N2V 1C5
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