Gestures - HP TouchSmart 9100 - Business PC Application Manual

messages, or you may need to override the default behavior of the default legacy
messages in your application.
You can also choose to wow your users with the best touch experience by having
your application register for touch input messages to handle them. The lowest level
raw touch data provided by Windows Touch API allows you to detect the action,
identify each touch point, its position and contact area. You then can calculate the
physic aspects of user touch actions and simulate lively physic responses engaging
the user actions.
With touch input messages, you can also choose to provide event sinks for
manipulation processors and inertia processors. This mechanism helps the
animation of complex gestures like rotation and translation at the same time,
deceleration of objects on their trajectories, bouncing off effects when hitting a
boundary, etc.
At the release of Windows 7, with WPF 3.5 SP1 the development support for new
multi-touch features is available for native code via Win32 and COM. WPF 4.0 is
expected to have support for all multi-touch features. In the interim, WPF
application developers have the following options:
Use .NET wrappers in Windows 7 Multitouch .NET Interop Sample Library or

Use stylus events

The following sub-sections summarize the basics of handling gesture and touch
input messages using unmanaged code. Subsequently you will note how to get
multi-touch data in a WPF application. Code excerpts from MSDN and other
sources are included for illustration.

Gestures

The following table lists the gestures defined in Windows 7 and the default
synthesized messages on applications that do not handle gesture messages.
Gesture
Tap (down and up quickly)
Double tap (down and up quickly twice)
Select (down, move over target(s), up)
Drag (down, move and up)
Press and hold (down, pause until the blue ring
appears around your finger then up)
Press and tap (press one finger on the target, then
quickly tap down the other finger. First finger
needs to be on the target.)
Two-finger tap (tap two fingers at the same time
and the target is the midpoint between two fingers
Panning (drag one or two fingers up and/or
Equivalent message
Mouse left-click
Mouse double click
Mouse select
Mouse left-drag
Mouse right-click
Mouse right-click
Not applicable
Mouse scroll wheel
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