What is the VSync

What is the VSync

VSync is short for Vertical Synchronization. The basic idea is to match the refresh rate of your FPS to that of your monitor. The goal is to avoid a phenomenon called tearing.

Each CRT monitor has its own refresh rate. The unit is HZ. The value is the number of times the display updates the picture per second. Different monitors support different refresh rates at different resolutions. It can range from low to 60 to high to 100. Note that it is not the FPS mentioned in your game. If you set a specific refresh rate, the monitor will always refresh the screen at that rate. Even the picture hasn't changed at all. Liquid crystal displays are different. Each pixel of the LCD will always be on when told to change. They don't need to refresh. But because of the way VGA(or DVI) works, LCDS have to get new images from the display card at a certain rate. This is why the LCD doesn't have to be updated, but it does have its own refresh rate.

I think everyone here understands FPS. It shows how many pictures the card can trace per second. This is obviously the higher the better. But for fast-moving games, it's hard to keep your FPS constant, and it varies depending on the complexity of what you see on the graphics card. So the tearing of the picture occurs.

VSync solves this problem by establishing a policy that does not allow images from the backup buffer to be copied into the display buffer before the monitor refreshes. If the FPS is higher than the refresh rate, that's fine. After the backup buffer has been updated, the system is in a wait state. When the monitor is refreshed, the backup cache is entered into the display cache, and the display card can paint new images in the backup cache, effectively limiting your FPS to the refresh rate of the monitor.