Embroidery data processing apparatus

An apparatus for processing embroidery data necessary for a sewing machine to form an embroidery in an area by filling the embroidery area with stitches, comprising:

• storing means for storing outline data representing an outline of an embroidery area which outline includes a curved line portion, said outline data including curved line data defining said curved line portion, said curved line data including data indicative of a characteristic of said curved line portion;
• modifying means for modifying said outline data and thereby transforming said outline and sadi embroidery area;
• and
• producing means for (a) dividing, by utilizing the modified outline data including the modified curved outline data representing the transformed curved line portion, a part of the transformed embroidery area, which part is defined by and said transformed curved line portion and a line portion of the transformed outline which is opposed to said transformed curved line portion, into a plurality of quadrangular blocks, each of which is defined by and between a pair of opposed straight line segments, so that the pairs of opposed straight line segments of said quadrangular blocks cooperate with each other to approximate sd transformed curved line portion and said opposed line portion and so that said quadrangular blocks cooperate with each other to approximate said part of said transformed embroidery area, (b) producing sets of quadrangular block data each of which set represents an outline of a corresponding one of said quadrangular blocks and comprises four sets of point data indicative of four vertices of said corresponding one quadrangular block, and (c) producing, by utilizing said sets of quadrangular block data, embroidery data necessary to form an embroidery inside sadi transformed outline, said embroidery data comprising stitch position-related data specifying at least one stitch position on an intermediate portion of at least one of said pair of opposed straight line segments of said each quadrangular block, said intermediate portion excluding said vertices of said each quadrangular block.