Sets the default magnification filter for textures when the texture is larger than the screen space it is displayed in. You can use a mode of 0 to use the nearest pixel, which will appear blocky, or 1 to use a linear filter which will look blurry. When the image matches the screen space exactly then both filters will look the same when there is a slight difference, nearest tends to be sharper, but may flicker as it changes pixel choice. You can set this value per image using SetImageMagFilter.
SetDefaultMagFilter( filter )