Graphic display device

A graphic display device which prepares graphic data representing a tool locus, using graphic form generating means, from an NC machining program and displays the tool locus on a display screen, said device comprising:

• graphic data storage means for storing the graphic data;
• program storage means for storing an NC machining program related to each grahic form represented by the graphic data with respect to a starting point of the graphic form;
• cursor move command input means for inputting a cursor move command;
• cursor control means for responding to the cursor move command from said cursor move command input means by accessing the graphic data stored in said graphic data storage means and displaying a cursor along the tool locus;
• and
• program display control means for responding to the passage of the cursor across each starting point stored in said program storage means by reading out of said program storage means the NC machining program stored therein corresponding to the starting point and displaying the program on the display screen.