@C0@lThe Tesseract Demo is a guided demonstration of

@C0@lhow we can visualize rotation in four dimensions.

@C0@lThe demonstration begins with the rotation of a

@C0@lsingle point, and builds up step by step to the

@C0@lfour dimensional analogue of a cube, called the

@C0@ltesseract.  



@C4@lPlease press "Point" to begin.



@C4@lPress "Reset" to stop everything and bring it

@C4@lback to its original configuration. 

@C4@lPress "Slow" or "Fast" under "MOTION" to start

@C4@lthe object moving.  Then press each object

@C4@lbutton (at left), starting at the top, and moving

@C4@ldown. At any point, use the LEFT mouse button to 

@C4@lrotate the view shown in the X_Y_Z_hyperplane.

@C0@l

@C0@lHow to make a tesseract:

@C0@lStart with a point.  Make a copy of the point,

@C0@land move it some distance away.  Connect these

@C0@lpoints.  We now have a segment.  Make a copy

@C0@lof the segment, and move it away from the first

@C0@lsegment in a new (orthogonal) direction.

@C0@lConnect corresponding points.  This is called

@C0@la square.  Make a copy of the square, and move

@C0@lit in a new (orthogonal) direction.  Connect

@C0@lcorresponding segments.  This is called a 

@C0@lcube.  Make a copy and move it in a new

@C0@l(orthogonal, fourth) direction.  Connect 

@C0@lcorresponding squares.  This is the tesseract.

@C0@l

@C0@lFor a more detailed description of the mechanics

@C0@lof this demo, please see the help panels and/or

@C0@lthe man page for NDview.

@C0@l

@C0@lThis demo was written in November, 1993 at

@C0@lthe Geometry Center.

@C0@lthanks to Stuart Levy for help with

@C0@lGeomview commands.

@C0@lby Olaf Holt

