lgblgblgb / xemu

Emulations (running on Linux/Unix/Windows/macOS, utilizing SDL2) of some - mainly - 8 bit machines, including the Commodore LCD, Commodore 65, and the MEGA65 as well.
https://github.com/lgblgblgb/xemu/wiki
GNU General Public License v2.0
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Add support for RRB reverse Y-row adjust #400 #401

Closed RetroCogs closed 5 months ago

RetroCogs commented 5 months ago

PR for issue #400

The change is pretty simple, changes char_fetch_offset to be signed so that it can support both +ve and -ve offsets, when fetching the offset from char data, if bit 12 (ScreenRAMByte1 bit 4) is set then negate the offset.

All usage locations stay the same.