Method and apparatus for data manipulation and system control in a selective deposition modeling system

A three-dimensional object is formed by selectively depositing successive layers (14) of build material from a print-head (9) having a plurality of orifices or nozzles (10(1)-10(96)), such as an ink-jet type of print-head. The print-head (9) is moved (X-Y control) relative to a support platform (15) in a series of scans in the X-direction offset from one another in the Y-direction and possibly overlapping. The orifices (10(1)-10(96)) extend transversely of the scan X-direction and may be set at an angle (α) to it to control the resolution perpendicular to the scan direction. The platform (15) is movable relative to the print-head in the Z-direction for forming each successive layer (14). The build material is a flowable material and may be a radiation-curable material, such as an ultra-violet curable photo-polymer. The data according to which each layer is formed may be manipulated according to a selected build style to determine the selective activation of the print-head orifices.