Port away from using QObject::sender()

By passing the sender object as an arg to the signal/slot.

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Pass TerminalDisplay parent arg when constructing a TerminalPainter object Ahmad Samir authored 14 hours ago

This way we can use it directly in the code, instead of QObject::sender() and casting.

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Call TerminalPainter methods directly instead of using signals/slots Ahmad Samir authored 1 hour ago

This is inherently faster than the singal/slot round trip.

Having a signal that returns anything other than void is an indication it should be a method not a signal.

Note that nothing outside of TerminalDisplay emits/uses those signals.