newer Qt versions want explicit cast to int (passing floats was OK before)

modules/gui/pymod/scene/custom_widget.py

modules/gui/pymod/scene/gradient_editor_widget.py

modules/gui/pymod/scene/hsc_widget.py

modules/gui/pymod/scene/immutable_gradient_info_handler.py

modules/gui/pymod/scene/trace_widget.py

modules/gui/pymod/scene/tube_widget.py