A printing device comprising an image generating unit that generates an image and a printing unit that prints the image generated by the image generating unit on a print medium, wherein the image generating unit comprises:
- a target data accepting unit that accepts target data comprising 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 circular shape based on the elliptical shape parameters;
- an inverse matrix calculating unit that calculates an inverse matrix of the transformation matrix;
- a transformation unit that transforms the gradation pattern parameters using the transformation matrix;
- a drawing unit that draws a gradation in the circular shape and stores the gradation for the circular shape in a memory in a bitmap format, the circular shape obtained by transforming the elliptical shape using the transformation matrix, based on the transformed gradation pattern parameters transformed using the transformation unit;
- and
- a gradation generating unit that generates the elliptical radial gradation by inversely transforming the gradation for the circular shape drawn and stored in the memory by the drawing unit, using the inverse matrix.