> O.k., I must admit that I don't know very much about consoles that came after the > Super Nintendo. I just noticed that these old consoles (NES, Super Nintendo) never > have tearing and the output is "hardwired" to the TV refresh rate without the > programmer having to do anything. Scrolling on the NES just works. You simply move > the x coordinate every frame and that's it. And I was hoping that modern consoles do > the same.
Even then you had to be careful - if you updated sprites/tiles while the display was updating instead of waiting for VBL (and you didn't have double-buffered sprite RAM) you'd get tearing. Updating mid-scan is the basis of raster effects, e.g. the "heat wave" effect on the airport scene in one of the KoF games is exploiting the same phenomenon as tearing when horizontally scrolling (updating X coordinate while the screen is updating to offset some lines of sprite from others).
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