Reading SCANLINE_L doesn't appear to work like hardware

[Yazwh0]

I'm not sure how its not working, as my intent was to read IRQLINE_L, but its def different between the emulator and hardware. Maybe off by one?

[Yazwh0]

To give context, I was reading the value adding 2 and storing into IRQLINE_L to get a line interrupt on the next line. This worked on the emulator, but didn't on hardware. Is SCANLINE_L based on the line being rendered into the buffer, vs IRQLINE which is the line being rendered out of the buffer?

[mooinglemur]

Most of the video code was written before hardware prototypes were in the hands of those writing the code. It likely needs a rewrite.