Patent ID: 8736635

Claim:
A figure drawing device comprising: a pixel division array generation unit generating an array of pixel divisions by dividing a pixel through which an edge line of a figure runs by a given number in the horizontal and vertical directions; an edge data setting unit setting up edge data for the array of pixel divisions generated by said pixel division array generation unit, the edge data presenting a pixel division at which filling starts and a pixel division at which the filling ends along the scanning line of a drawing region; a pixel division row shifting unit shifting the array of pixel divisions for which said edge data are set up by said edge data setting unit in the direction of said scanning line on the basis of row of pixel divisions arranged in the direction of said scanning line by a given number of pixel divisions determined for said row of pixel divisions; a contracted pixel column generation unit calculating the sums of said edge data of pixel divisions on the basis of said row of pixel divisions within the pre-shift range of said array of pixel divisions in a set of pixel divisions shifted by said pixel division row shifting unit, and generating a column of contracted pixels storing said sums of edge data, said column of contracted pixels having a width equal to one pixel in the direction of said scanning line and consisting of the number of contracted pixels obtained by dividing in the direction perpendicular to said scanning line; a mask pixel array generation unit generating an array of mask pixels indicating the contracted pixels to be filled from an array of contracted pixels obtained by arranging said columns of contracted pixels generated by said contracted pixel column generation unit according to the array of undivided pixels; an occupancy rate calculation unit calculating the fill occupancy rate of a pixel through which said edge line corresponding to said column of contracted pixels runs from the sum of the products of the column of contracted pixels and adjacent columns of contracted pixels and given weighting coefficients for individual contracted pixels together on the basis of column of contracted pixels of said array of mask pixels generated by said mask pixel array generation unit; a figure drawing unit filling the pixels within said figure with a first gradation and filling the pixels through which said edge line runs with a second gradation that is lower than the first gradation and determined according to the occupancy rate calculated by said occupancy rate calculation unit so as to draw the figure on a display screen.