Flickering not present on real hardware

[GValiente]

Test ROM

In the scanline marked by the red arrow, there's some flickering not present on real hardware. Map scale is updated each scanline in a H-Blank interrupt, so the flickering is probably related to that:

[fleroviux]

Observation: the flickering appears to always be in the same (close to center) scanline, even after moving on the map.

[alyosha-tas]

I was testing this out on Gameboy Player today, and the image I get is the same as in NanoboyAdvance with LCD ghosting turned on. So it seems the behaviour here is correct.

There is obvious flickering with LCD ghosting turned off, but that's likely not an emulation accuracy issue.