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Understanding QTouchEvent

  • Hello,

    Just trying to wrap my head around QTouchEvent. Any help/advice is appreciated.

    Specifically I'm a bit confused when a touch event is fired (for e.g. TouchBegin); does this represent only one unique touch point? If so why is there a list of touch points inside QTouchEvent?

    If not is it the case that Qt will group together several TouchBegin instances that happen in a given time fraction and deliver it as one event, with the list of points encapsulated in the event? Likewise a QTouchUpdate event will contain information about several touch points that are being updated at that time?

    Also I assume that @QTouchEvent::TouchPoint::id@ will remain consistent throughout TouchBegin, TouchUpdate and TouchEnd. Meaning that in different touch events if I see a point with the same id, it is the same touch point that both events are referring to. Is this assumption correct?

    FYI: I've been working with TUIO for sometime, so if someone is familiar with both Qt and TUIO a comparative explanation would be much easier for me to understand.

    Still I'd really appreciate any help at all.


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