DEFINITION OF A RECTANGULAR 3D VIEW, Y-AXIS VERTICAL
CALL SEQUENCE
TV3CAY (WKID, VIEWID, XC, YC, ZC, XO, YO, ZO, ZOOM, VIEWPT)
INPUT PARAMETERS
INTEGER WKID
INTEGER VIEWID
REAL XC,YC,ZC
REAL XO,YO,ZO
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.
- XO,YO,ZO
- Coordinates of the observer with respect to the point in the scene being
viewed.
- 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 at XO,YO,ZO is given in
rectangular coordinates in relation to the same point XC,YC,ZC. The
projections used by the view thus defined are in perspective: the distance of
the observer to the point XC,YC,ZC has a direct effect on the appearance in
perspective (the smaller the distance, the larger the parallax error), unlike
the zoom factor, which has no effect on the distortion of the image. The
Y-axis will be represented vertically as shown in the figure below:
