While developing multipoint-based application,we always work to find which pointer trigger the event. We can do it simply because every mulitpoint object is assigned with unique ID in inizialitation phase. And the scenario for that is various.
For example,we usually provide a page for gamer to type their nick name which will be used along the game. In normal case, we could use keyboard, or joystick. However, in multipoint application, to enable every player types his name simultaneously, we have to use different approach. One of my favourite, providing the app with multipoint-aware virtual keyboard.
This is the example below. We provide some Multipoint Buttons - the control includes in samples v1.1 - to act as keyboard tuts. Assign the alfabet and for that button add proper event handler that will find which mouse triggered the multipoint event. Simply doing iteration in mousedevicelist collection where multipoint object saved. Then, we need an usercontrol to hold the text. In this example, I make usercontrol that consist of image, textblock and device info. Image is used to hold image cursor, the textblock for the text and device info is the reference to object in mousedevicelist.
In the beginning,the multipoint mode is inactive. Press Ctrl+M to activate multipoint mode and there will be some usercontrols for every mouse connected to the machine. Now, the gamer could type their name.