Function UpdateWidgetColour

src/openrct2-ui/scripting/CustomWindow.cpp:1216–1241

    }

    void UpdateWidgetColour(WindowBase* w, WidgetIndex widgetIndex, Colour colour)
    {
        if (w->classification == WindowClass::custom)
        {
            auto& customInfo = GetInfo(static_cast<CustomWindow*>(w));
            auto customWidgetInfo = customInfo.GetCustomWidgetDesc(w, widgetIndex);
            if (customWidgetInfo != nullptr)
            {
                auto& widget = w->widgets[widgetIndex];

                auto lastColour = customWidgetInfo->Colour;
                if (lastColour != colour && colourIsValid(colour))
                {
                    customWidgetInfo->Colour = colour;
                    widget.image = getColourButtonImage(colour);

                    auto* windowMgr = GetWindowManager();
                    windowMgr->InvalidateWidget(*w, widgetIndex);

                    std::vector<JSValue> args;
                    args.push_back(JS_NewInt32(customWidgetInfo->OnChange.context, EnumValue(colour)));
                    InvokeEventHandler(customInfo.Owner, customWidgetInfo->OnChange, args);
                }
            }
        }
    }

    void UpdateWidgetSelectedIndex(WindowBase* w, WidgetIndex widgetIndex, int32_t selectedIndex)
    {