PURPOSE: To easily and correctly form a camera copy of a printed matter with complicated graphics or the like by using a block copy formed by a computer-assisted design apparatus in a composition conducted on a display of a manual photocomposing machine.

CONSTITUTION: Plot data S1 imparted to a display CPU 37 is written in a buffer memory and converted to a form which can be displayed. Namely, for example, the imparted plot data S1 is three-dimensional data, it is converted to two-dimensional display data S2 by a conversion matrix and written in a frame memory. The display data S2 is supplied to a CRT display 38, whereby a block copy 31 formed by a CAD 30 can be displayed on the display 38 of a composition system. Then, using the displayed block copy 31, alphabetic character pattern information S4 and feed information S5 are generated correspondingly to the display content on the display 38. For example, the operating a keyboard of an input device 33, a matrix cabinet pattern for conducting a required ruling is positioned on an optical axis 25.