Wpf Stylus Events - HP TouchSmart 9100 - Business PC Application Manual

if (bHandled){
// if you handled the message, close the touch input handle and
return
CloseTouchInputHandle((HTOUCHINPUT)lParam);
return 0;
}else{
// if you didn't handle the message, let DefWindowProc handle it
return DefWindowProc(hWnd, WM_TOUCH, wParam, lParam);
}
}
Consider the following when handling WM_TOUCH:
Pass unconsumed messages to DefWindowProc to ensure all messages are

handled appropriately.
Call CloseTouchInputHandle to close the touch input handle for messages that

your application handles.
 Be aware that by default, touch messages are coalesced and palm detection
are enabled. Palm detection may affect the performance of your application
unnecessarily. You can turn both of these off in the call to
RegisterTouchWindow.
Note that WM_TOUCH messages are "greedy". Once Windows sends the first

touch message to a window, all subsequent touch messages are sent to that
window until another window gets focus.
Interpreting touch input messages is usually complex. You may want to utilize COM-
based manipulation processors and inertia processors to make handling touch input
messages easier for you. You can feed raw touch input messages to a manipulation
processor and get manipulation delta events back with all the deltas you want to
know to respond to touch messages: translation delta, scale delta, expansion delta,
rotation delta, etc. With this help, you can respond to gesture combinations like
zoom and rotate, or rotate and translate without having to do a lot of calculations
yourself. You can also use an inertia processor together with a manipulation
processor to simulate object physics.
More on manipulations and inertia is available on MSDN, section Manipulations
and Inertia at http://msdn.microsoft.com/en-us/library/dd317309(VS.85).aspx.
You may also refer to Implementing Windows Touch with Multiple Manipulation
Processors blog at http://gclassy.com/2009/08/06/implementing-windows-touch-
with-multiple-manipulation-processors/.

WPF Stylus Events

Besides handling gesture and touch input messages using unmanaged code, you
can also utilize stylus events in WPF to get touch data. This path is for those who
want to develop with WPF prior to WPF 4.0. Andrew Eichacker showed how to get
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