Graphics Reference
In-Depth Information
While in the camera view, using the Alt+Ctrl / Option+Control key combo with the right
mouse button adjusts the focal length of the camera and enables you to zoom in and out, as
opposed to actually moving the camera in and out in space.
The real complication comes with rotation. Rotation works based on the combination of two axes. Con-
sider the way we rotate in two dimensions. With the x and y axes covering the screen horizontally and ver-
tically, we can rotate along the perpendicular axis (in this case, z). Because only two axes are present, we
can rotate in only one dimension. The addition of the third axis adds two more possible rotation options, as
we now have three planes to consider (xy, xz, and yz). As if this did not complicate things enough, there
is one more point to consider: the center of rotation. In a 2D layout, we rotate relative to the center of the
document. If we were to rotate only in relation to the origin (center of space), we would be very limited in
our access to the work area.
To move freely in a 3D workspace, we need to rotate our viewport dynamically. So there are three types
of rotation to deal with:
• Around the view focal point
• On a virtual tripod
• Rolling around the axis perpendicular to the perspective
Figure 1-7
shows a model from the front.
Figure 1-8
shows that same object with the view rotated to
show the depth of the model.
Figure 1-7:
Flat front view of a model
Figure 1-8:
Perspective view of a model
