DEFINITION OF A SPHERICAL 3D VIEW AROUND Y
CALL SEQUENCE
TV3SPY (WKID, VIEWID, XC, YC, ZC , PHI, TETA, D, ZOOM, VIEWPT)
INPUT PARAMETERS
INTEGER WKID
INTEGER VIEWID
REAL XC,YC,ZC
REAL PHI
REAL TETA
REAL D
REAL ZOOM
REAL VIEWPT (6)
ARGUMENTS
- WKID
- Identifier of the workstation on which the view is defined.
- VIEWID
- Index of the view to define.
- XC,YC,ZC
- Coordinates (in normalized space [0-1] × [0-1] × [0-1]) of the
point in the scene to center on.
- PHI
- Angle phi around the Y-axis, expressed in degrees.
- TETA
- Angle theta, expressed in degrees.
- D
- Distance from the observer to the view point, in normalized space [0-1]
× [0-1] × [0-1].
- ZOOM
- Zoom factor to apply to the image.
- 1
- the image is normal
- 2
- the image is enlarged to twice the normal size
- 0.5
- the image size is reduced to half its normal size, etc)
- VIEWPT
- Viewport (see TVIEWC).
EFFECT
This function defines the view identified by the integer VIEWID. The observer
looks toward the point XC,YC,ZC and his position is given in spherical
coordinates in relation to the same point XC,YC,ZC. The projections used by
the view thus defined are in perspective: the distance D of the observer to the
point XC,YC,ZC has a direct effect on the appearance in perspective (the
smaller is D, the larger are the parallax errors) unlike the zoom factor, which
has no effect on the distortion of the image.
