nnarain / gameboycore

Gameboy Emulator Library
MIT License
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StreetFighter II - Graphics glitch #223

Open GGORZ10227216 opened 5 years ago

GGORZ10227216 commented 5 years ago

Hi, I am checking my emulator's behavior with gameboycore.

And I found a weird graphics bug when running StreetFighter II :

Screenshot from 2019-09-20 15-27-38

This glitch will appear when entering the battle stage. After some research, I discovered there are some reasons can cause this bug :

  1. The LCD working sequence : I change the working sequence about LCD :

      i.) Calling renderScanline() in HBLANK_CYCLES instead of LCD_TRANSFER_CYCLES
           This will eliminate the white line between player's hp bar and the battle stage.
    
      ii.) Do the compareLyToLyc() before updateLY(). This will fix 90% blurred frame.
  2. Remove IME check in the compareLyToLyc(). This will fix the last 10% blurred frame.

nnarain commented 5 years ago

Hey, thanks for reporting the bug! I'll take a look at it. I think I've seen something similar for games that support Super Gameboy as well.