The halftone printing process approximates a continuous tone image using only black ink on white paper. This can be achieved using a pattern of dots of varying size, shape, or mutual distance.
The halftone process in this Demonstration uses a pattern of black dots whose diameter is proportional to the local tone level.
The resolution slider sets the number of dots for the width of the image. The dot size slider varies the average dot radius by changing the ratio between tone level and point size.
The appearance of moiré-like artifacts can be avoided by dithering. The dithering used here is achieved by randomly offsetting the dots from their central position in the pattern. The dither slider sets the maximum allowed offset between the centers of the dots and the pattern positions.