Transformer is a tool to manipulate the wrap transforms of geomview objects. When transformer is started, it will read in the wrap transform of the target object. The transform will be displayed at the top of the panel.
The displayed transform may at any time be set to the wrap transform of the geomview target object by pressing the "Read" button at the bottom of the panel. Note that the transform does not automatically update whenever the target object moves. The transform may also be set to the identity by pressing the "Identity" button at the bottom of the panel.
The transform may also be applied to the geomview target object by pressing the "Apply" or "Set" button. The "Apply" button will cause the current wrap transform of the current target object to be postmultiplied by the displayed transform. The "Set" button will cause the wrap transform of the target to be replaced by the transform. Note that the transform of the geomview target is not updated automatically when the transform displayed in the panel changes.
The displayed transform may be modified directly by changing the numbers in the matrix. In addition, a rotation, translation, or scale may be applied to the object. To rotate the object, enter the appropriate number of degrees or radians in the input field next to the "Degrees" buttons and press the "Rotate" button. The displayed transform will then be postmultiplied by a rotation matrix of the requested amount about the specified axis. In a similar fashion, the translate and scale sections of the panel may be used to update the transform.
All operations are Euclidean.
The following keyboard shortcuts apply:
R Rotate
T Translate
S Scale
a or Space Apply
Return Set
r Read
i Identity
q Quit
The transform is read from the current target when the program begins or the read button is pressed. The transform of the current target is modified by or set to the displayed transform when the "Apply" or "Set" button is pressed. There is no check that the user has not changed the geomview target between these two operations. Although the results of such an operation will be correct according to the specifications in this man page, the results may be unexpected.
Celeste Fowler email: fowler@geom.umn.edu The Geometry Center phone: (612) 626-8304 1300 South Second Street Minneapolis, MN 55454