PixelDisplay.scale is a scaling factor controlling how this pixel display is rendered on
screen. The default value of 1 means that one pixel in the display
draws as 1 pixel on screen; 2 double the scale, making each pixel
appear twice the normal width and height.
You may assign either a simple number to scale the same way in width
and height, or a list
[x scale, y scale] to scale differently
in X and Y.
gfx.scale = 5 // makes every gfx pixel 5 times bigger in X and Y