Patent ID: 8605112

Claim:
A graphics drawing apparatus drawing a graphic, comprising: a memory corresponding to a two-dimensional coordinate system including an X-axis representing a direction in which consecutive memory addresses are arranged and a Y-axis intersecting the X-axis; a generation unit, when a sequence of two-dimensional coordinates of vertices including a leading vertex which is input first and last, a plurality of intermediate vertices which are input after the leading vertex and the trailing vertex which is input after the plurality of intermediate vertices is input, generating a virtual vertex having virtual vertex coordinates by setting the X-coordinate value of the leading vertex to the X-coordinate value of the virtual vertex coordinates and setting the Y-coordinate value of one of the plurality of intermediate vertices to the Y-coordinate value of the virtual vertex coordinates; and a drawing unit performing a drawing process drawing in the memory a partial graphic after generating one or more virtual vertices corresponding to respective intermediate vertices among the plurality of intermediate vertices, the partial graphic being defined by the one or more virtual vertices and the respective intermediate vertices, the drawing unit performing the drawing process drawing in the memory a trailing partial graphic defined the reading vertex, the trailing vertex and the virtual vertex corresponding to the trailing vertex when the leading vertex is input after the trailing vertex is input, wherein when a part or all of a first partial graphic defined by a first intermediate vertex, a second intermediate vertex and the virtual vertices corresponding to the first intermediate vertex and the second intermediate vertex overlaps a second partial graphic defined by the intermediate second vertex, a third intermediate vertex input after the second vertex and the virtual vertices corresponding to the second intermediate vertex and the third intermediate vertex, the drawing unit deletes the overlapping portion from the memory to output a graphic having vertices at the sequence of two-dimensional coordinates of vertices.