Patent ID: 8259352

Claim:
An image generating device comprising: a target data accepting unit that accepts target data including an image drawing instruction for drawing an elliptical radial gradation; an acquisition unit that acquires the image drawing instruction from the accepted target data; an extraction unit that extracts elliptical shape parameters specifying an elliptical shape of the elliptical radial gradation and gradation pattern parameters specifying a gradation pattern to be drawn in the elliptical shape from the acquired image drawing instruction; a transformation matrix generating unit that generates a transformation matrix for transforming the elliptical shape into a perfect circular shape based on the elliptical shape parameters; an inverse matrix calculating unit that calculates an inverse matrix of the transformation matrix; a perfect circle parameter calculating unit that calculates perfect circle parameters specifying perfect circles, each of the perfect circles being to be drawn with a uniform color, based on the extracted parameters assuming that the gradation pattern to be drawn in the elliptical shape is drawn in the perfect circular shape obtained by the transformation of the elliptical shape by the transformation matrix; an ellipse parameter calculating unit that calculates ellipse parameters specifying ellipses, each of the ellipses being to be drawn with a uniform color, by inversely transforming the calculated perfect circle parameters by use of the inverse matrix; and a gradation generating unit that generates the elliptical radial gradation based on the ellipse parameters calculated by the ellipse parameter calculating unit and the gradation pattern parameters extracted by the extraction unit, wherein the gradation pattern parameters comprise positional information on a center of the gradation drawn in the elliptical shape, and the image generating device further comprises: a transformation unit that transforms the positional information on the center of the gradation by use of the transformation matrix; and a setting unit that sets a transformed center of the gradation, which is determined by transformed positional information, on a coordinate axis intersecting a center point of the perfect circular shape, and the perfect circle parameter calculating unit calculates the perfect circle parameters specifying the perfect circles by calculating a center position of each perfect circle, to be drawn with a uniform color, along the coordinate axis.