Can SITL simulate modified code and physical model?

Hello to everybody,we intend to use SITL to simulate the real flight but I have a few questions:
1.we made some changes to the code,basically in the attitude control library and the motors output.Is it possible for SITL to simulate the effect of our modification?
2.Does SITL simulate the physical model of the vehicle, like providing the adjustable parameters of the weight,the size of propella etc.?
I will appreciate it if anyone could help!:grinning:

yes in all SITL and yes in realflight

Does it mean the physical model I mentioned above can’t be simulated in SITL?

it can in SITL using realflight but not in the built in SITL (not without getting into the code anyway)

Got it.Thanks a lot!

I have anothor question, where is the physical model when we use the mavproxy and SITL without realflight.

In the main code, this is copter, there is are files for several different vehicle types https://github.com/ArduPilot/ardupilot/blob/master/libraries/SITL/SIM_Multicopter.cpp

thanks for your reply and I will read it carefully