A method is provided of generating a pattern image used to form a pattern on a surface of a fabric using laser irradiation. A plurality of parameters associated with laser irradiation units are input into a user interface. The parameters include an area parameter, a laser irradiation unit density parameter, optionally a discontinuity parameter, and a dye removal parameter. A plurality of laser irradiation units arranged in a pattern area of a user interface based on computer processing of the inputted plurality of parameters is received for viewing at the user interface. The laser irradiation units collectively establish the pattern image for viewing by the user.