Have you tested the effect of -oversteer on pedal inputs?
When I did my 'oversteer' hack originally, it fortunately didn't effect pedal inputs.
In my original hack, I only apply oversteer in apply_analog_min_max IF the host control is IPT_PADDLE (I.e. What OutRun/HangOn/WecLeMans etc... uses for steering) or IPT_AD_STICK_X (I.e. What SCI etc... uses for steering). For most driving games, I think accelerator/brake pedal inputs are set to something else other than IPT_PADDLE or IPT_AD_STICK_X, so I got away with it.
In summary, you only really want to do oversteer if the answer to the following is all YES:
- Does the original arcade machine have a steering wheel (or handle bars)?
- Does the original arcade machine restrict you from turning its steering wheel (or its handle bars) if you try to turn them in a particular direction (I.e. does it have limits, rather than being free spinning)?
- Are you trying to control it (emulated control) with a mouse X or mouse Y axis?
To ensure this happens, perhaps in apply_analog_min_max, you could have logic along the lines of:-
if((oversteer_enabled) && (HostControl == oversteer_host_control) && (EmulatedControl == oversteer_emulated_control))
do oversteer here...
Where it is possible for the user to specify (via command line) their choice_of_host_control (E.g. IPT_PADDLE ) and choice_of_emulated_control (E.g. MOUSE_X_AXIS)? Just a thought anyway