Watercolor simulation in computer graphics
AssigneeAXA Corporation
InventorsYao D. Hwong, Chin-an Cheng, Ming T. Su
Life of this patent
Estimating the term…
Abstract
Watercolor effects are simulated in computer graphics by defining a brush shape and brush type, selecting a wetness level for the drawing area and, in accordance with the selected wetness level, causing the brush stroke to merely interpolate the brush color with the pre-existing color in the stroked area, create a texture effect of diminishing brush color, or create a smearing effect by interpolating the pre-existing color at a new brush position with that of the previous brush position before interpolating it with the brush color. Apparatus is also disclosed for selecting various brush attributes and brush color parameters.
Claims20
Apparatus for simulating watercolor effects on a graphics computer having a color screen and a drawing tool for selectively identifying cursor position pixels on said screens comprising:
- a) means for selecting a predetermined wetness level for the watercolor paper represented by said screen;
- b) means for defining a brush shape centered upon said cursor position pixel;
- c) means for selecting a water content parameter and a color content parameter, and a brush color to be associated with said brush shape;
- and
- d) means for causing said brush shape to produce, along the path of the stroke described by it when said cursor position is moved across said screen, a color effect which is a function of said wetness level, said water and color content parameters, said brush color, and the length of said stroke.
Apparatus for producing a brush texture in computer graphics, comprising:
- a) means for defining a multi-pixel brush shape on a screen;
- b) means for assigning a brush color to said brush shape;
- c) means for moving said brush shape across said screen;
- d) means for iteratively calculating a color for each pixel of said brush shape in successive positions of said brush shape on said screen;
- and
- e) means for iteratively decrementing the intensity of said brush color at different rates for different pixels of said brush shape.
Apparatus for producing a smearing effect in computer graphics, comprising:
- a) means for assigning to selected pixels of a screen a pre-existing color;
- b) means for defining a multi-pixel brush shape on said screen;
- c) means for assigning a brush color to said brush shape;
- d) means for moving said brush shape across said screen;
- e) means for iteratively calculating, for successive positions of said brush shape, a color for each pixel of said brush shape, said calculating means including:
- i) means for interpolating for any given brush shape pixel, said pre-existing color at a first position of said brush shape pixel with said pre-existing color at a second position of said brush shape pixel;
- and
- ii) means for interpolating the thus interpolated color with said brush color;
- and
- f) means for displaying the color produced by said second interpolation as the color of said second position of said brush shape pixel.
Dependencies are inferred from the claim text.