IDE: fix again ruberband with gtk3.
DC logical functions are now disabled when using GTK3.
Apparently using XOR was still having an effect.
Use regular black pen with no logical funciton instead.
Project overview
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In order to target the widest possible range of programmable devices and keep efficient, Beremiz use C code as an intermediate language.
To be executed, C needs to be compiled. `GCC <http://gcc.gnu.org>`_ serve that purpose perfectly.
PLC program is expressed in languages defined in IEC-61131, including graphical languages. Thanks to PLCopen TC2, those graphical languages have a standardised representation, in XML.
To be continued.