DEFINITION OF A CARTESIAN 3D VIEW - Z AXIS VERTICAL
CALL SEQUENCE
void tview3_perspect_z_coord (wkid, view_ind, pointc, obs_pos, zoom, viewport)
INPUT PARAMETERS
Pint wkid;
Pint view_ind;
Ppoint3 *pointc;
Ppoint3 *obs_pos;
Pfloat zoom;
Plimit3 *viewport;
ARGUMENTS
- wkid
- Identifier of the workstation on which the view is defined.
- view_ind
- Index of the view to be defined.
- pointc
- Coordinates (in normalized space [0-1] × [0-1] × [0-1]) of the
point of the scene concerned.
- obs_pos
- Observer position in relation to the point of the scene concerned.
- zoom
- Zoom factor applied to the image.
- 1: the image is normal
- 2: the image is magnified by two
- 0.5: the image is reduced by 2
- etc...
- viewport
- Viewport (see tview_config).
EFFECT
This function defines the view identified by the integer view_ind. The
observer looks toward the point pointc and his position,
obs_pos, is given in rectangular coordinates in relation to the same
point pointc. The projections used by the view thus defined are in
perspective: the distance of the observer to the point pointc 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 Z axis will be represented
vertically as shown in the figure below:
