The same game of 160 × 120 pixels fitted to the page four ways, changed while it runs with useGame().setScaling. The game draws the same pixels every time: only how big they are painted changes. Make the window bigger and smaller to see each one follow it.
1 is 'integer', the largest whole multiple of the screen's own pixels: crisp, with bars when it does not fit exactly. 2 is 'contain', as large as fits, with fractions: the frame and the stripes show pixels of different widths. 3 is 'fill', stretched both ways. 4 is 'none', its own size. T switches the pixels between square and a television's 8:7 (setPixelAspect).