halftone gritty noise texture. grunge grit pixel gradient background. black dotted sand noise wallpaper. retro pixelated

dot bitmap texture background noise halftone grain vintage grit speckle cartoon overlay grunge retro duotone manga effect digital poster old semitone grid spot sand dust snow pattern grainy rough vector gravel rust bg dirt paper book backdrop grungy distressed particles screen bw gritty halfton dotted pixel gradient comic poka