2.9 KiB
I see "tearing" when a game scrolls. How can I enable vsync?
higan supports synchronizing video output to the display's vertical-synchronization (or "vsync") signal, but the option is hidden because it often causes more problems than it solves (see the next question).
To enable video synchronization:
- Open the higan's configuration file,
settings.bml- On Windows, look in
%LOCALAPPDATA%\higanor besidehigan.exe - On Linux, look in
~/.local/share/higan
- On Windows, look in
- Open it in your favourite text editor (Windows Notepad will corrupt the file, use WordPad if you don't have anything better)
- Find the line that says "Video"
- Somewhere below that, find an indented line that says "Synchronize:false".
- Change "false" to "true"
- Save your changes to
settings.bmland restart higan
Why is video synchronization a problem for higan?
The short version: Turning on video synchronization cleans up video tearing, turning on audio synchronization cleans up audio glitches, but turning on both makes audio glitches worse.
The long version: Enabling video synchronization locks the frame-rate of the emulated console to the frame-rate of your computer's display. If your display's refresh rate exactly matches the emulated console's, games play at the correct speed and everything's fine.
However, modern 60Hz displays do not always match the emulated console's refresh rate:
- The Super Famicom usually runs a little faster than 60Hz
- the PAL variants of most consoles run at 50Hz
- the WonderSwan runs at 75Hz
- While the Game Boy does run its LCD at 60Hz it can turn it off and on at any time, requiring emulation to pause until it can get back in sync with the computer display.
Because of these frame-rate differences, enabling video synchronization can force games to run faster or slower than intended.
The consoles that higan emulates produce video frames and audio samples at a particular rate. If video synchronization causes the emulated console to run, say, 5% faster than intended, that means audio samples are also being produced 5% faster. You might not notice the changed game speed, but you'll almost certainly notice the game's audio glitching constantly as your sound card tries to keep up.
Enabling audio synchronization normally fixes this kind of audio glitching, but with video synchronization it makes things worse: audio is likely to glitch while higan waits for a video frame to be shown, and video is likely to stutter while higan waits for an audio buffer to complete.
This game is running too fast!
TODO
games run in fast-forward if there's no audio device https://board.byuu.org/viewtopic.php?p=44138#p44138