ManipulationDelta is negatively affected when simultaneously doing SurfaceImageSource rendering in a XAML metro app

Question

I have a XAML metro app where

1. I have a SurfaceImageSource that is being updated via a CompositionTargetRendering via the RenderAll() method. ~60fps is achieved

2. I am simultaneously tracking the pointer movement and getting the ManipulationDelta of the main windows canvas.

So basically I have 2 major UI pieces updating simultaneously (the Dx surface & the Sensor information(returning ManipulationDelta information))

Problem : It seems that the manipulation delta information is being negatively impacted by the excessive SurfaceImageSourceTarget.RenderAll() calls.

I find that I need to limit the framerate of the RenderAll calls to compensate for the negative impact.

Basically I am forced to move to a 30fps in my DxSurface if I want to capture reliable ManipulationDelta information..

Is anyone else experiencing this issue ?

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Answer 1

For those interested I posted my sample code and a blog post (with videos) showing and explaining the issues I was having with ManipulationDelta + Direct2D Rendering..

http://advertboy.wordpress.com/2012/05/20/radial-gradients-mini-path-geometry-sprites-infinite-scrolling-inertial-canvas/

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Answer 2

Hello,

 

Thanks for your feedback, I will involve more experts to investigate it.

 

Best regards,

Jesse

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Jesse Jiang [MSFT]
MSDN Community Support | Feedback to us

Answer 3

It sounds like you're encountering a known issue where doing a certain amount of work every frame in the CompositionTarget.Rendering callback can affect input frequency.  Hopefully this should be addressed in the next release.