
i
i
i
i
i
i
i
i
144 6. A Pocket 3D Theory Reference
Figure 6.18. The field of view φ governs how much of the scene is visible to a camera
located at the viewpoint. Narrowing the field of view is equivalent to using a zoom
lens.
therange0→ (X
max
− 1) horizontally and 0 → (Y
max
− 1) vertically, where
X
max
and Y
max
refer to the number of pixels in the rendered image in the
horizontal and ver tical direction, respectively. The coordinate origin (0, 0) is
in the top-left corner (see Figure 6.17).
The distance of the projection plane from the viewpoint can be chosen
arbitrarily; setting it to a value of 1 simplifies the calculations. Thus, if the
plane of projection is