Patent ID: 7221379

Claim:
A method of object manipulation in a computer system comprises: displaying a first three-dimensional object on a display, wherein the first three-dimensional object comprises a second three-dimensional object and a third three-dimensional object, wherein the first three-dimensional object has an associated first volume; displaying a control indicator on the display, wherein the control indicator is associated with the first three-dimensional object; receiving an offset in a first dimension for the control indicator in response to user input with a user input device; forming a modified first three-dimensional object having an associated second volume in response to the offset comprising: automatically scaling the first three-dimensional object in a first dimension by a first amount in response to the offset of the control indicator; and automatically modifying a cross-section of the first three-dimensional object perpendicular to the first dimension in at least a second dimension in response to the offset of the control indicator, in response to the associated first volume, and in response to a constraint; wherein the associated second volume is determined in response to the associated first volume; and wherein the constraint comprises having a size and a shape of a first end of the first three-dimensional object being equal to a size and a shape of a first end of the modified first three-dimensional object.