Unfortunately, I did not manage to produce a satisfying result. I have checked online for Wii specs in 4:3 and here is what I found (not sure if it is true or how to check it). Wii in 4:3 mode has an internal resolution of 640×480 and adds pillarbox of 40px on each side to produce a 720×480 output. I have a few hypothesis on how I should tweak the settings to correct the aspect ratio but so far, I have not produced appropriate result nor do I know if it is even possible. Maybe someone can help me with the right settings if it is indeed possible. So far, I have only tweaked h.active and h.samplerate because I do not know how the other settings work, maybe someone more knowledgeable could help me on what the sampling option does effectively.
Here are the 3 hypothesis I would like to try.
1) set h.active to 640 and crop the extra 40px on both side (not sure if it is doable) let the display stretch the 640×480 output as it should. So far, it seems that setting h.active to 640 gets stretched by my display which is weird, maybe I have to change other settings line synclen but I do not understand the relation between each settings yet. Am I wrong in assuming that a similar process is used for the dreamcast? Someone else mentioned it before and to my knowledge, it should be the same no? I have tried h.samplerate of 800 and in 640 h.active and it looks exactly the same as 858/720 on my display. I do not have a dc to test this on so it might be my display or it might be that the wii might need different sampling options.
2) leave h.active at 720 but shrink the whole horizontal line to 75% and add pillarbox. H.active of 720 is well handled by my display but I am not sure this solution is supported by the ossc hw.
3) double h.active to 1440 but only apply a 1.5 multiplier on horizontal line, adding pillarbox on both side to fill the 1440 space. Again, not sure if this is doable, I have tried a few combinations using unsamplex2 on and such but I could not produce any significant output.
I believe I understand how h.active works but maybe someone could explain exactly how h.samplerate and h.synclen works or how it should be used depending on h.active (if these 2 settings are even dependent)
Thank you for reading through.