Adobe Inc.
Digital overpainting controlled by opacity and flow parameters

Abstract:

In some embodiments, a graphics manipulation application accesses, for a received brushstroke input, brushstroke parameters that include a maximum alpha-deposition parameter and a fractional alpha-deposition parameter. The graphics manipulation application computes an alpha flow increment from the maximum alpha-deposition parameter and the fractional alpha-deposition parameter. The graphics manipulation application computes an output canvas color from the alpha flow increment and a current canvas opacity, and obtains an output canvas opacity based on the current canvas opacity and the maximum alpha-deposition parameter. If the current canvas opacity exceeds or equals the maximum alpha-deposition parameter, the current canvas opacity is selected as the output canvas opacity. Otherwise, the graphics manipulation application computes the output canvas opacity by increasing the current canvas opacity based on the alpha flow increment. The graphics manipulation application updates a canvas portion affected by the brushstroke input to include the output canvas opacity and the output canvas color.