3D ProjectionControl matrix & point of view

• To: visad-list@xxxxxxxxxxxxx
• Subject: 3D ProjectionControl matrix & point of view
• From: Stuart Wier <wier@xxxxxxxxxxxxxxxx>
• Date: Mon, 30 Oct 2000 09:21:12 -0700

Where is there a description of the ProjectionControl matrix?

And if someone already knows the answer to this particular
question, please let me know.  
What values are used in the ProjectionControl matrix
to switch a 3D display to a view from on top, and from south, north,
east, and west?

Alternately, what values are used in:

/** create a projection matrix appropriate for this graphics API
      from x, Y and Z rotation angles, from a scale factor, and from
      X, Y and Z translation amounts;
      these creates the matrix format used by the getMatrix and
      setMatrix methods of ProjectionControl */
  public double[] make_matrix(double rotx, double roty, double rotz,
                              double scale, double transx,
                              double transy, double transz);

to create these points of view?

Are any of these angles (rotx etc.) equivalent to azimuth (view from an angle
measured
from north 0 to 360) and elevation (something like 90 = from overhead
and 0 = from side)?

Stu Wier

-- 

Stuart Wier                              UCAR Unidata Program
wier@xxxxxxxxxxxxxxxx                           P.O. Box 3000
http://www.unidata.ucar.edu/staff/wier      Boulder, CO 80307

• Follow-Ups:
  • Re: 3D ProjectionControl matrix & point of view
    • From: Bill Hibbard