Page 168 - Computer Graphics Handout

The matrix M transforms the point

to the point

At first glance, q may not seem sensible; however, when we remember that we have to divide the first three components by the
fourth to return to our original three-dimensional space, we obtain the results

which are the equations for a simple perspective projection. In homogeneous coordinates, dividing q by its w component replaces
q by the equivalent point

We have shown that we can do at least a simple perspective projection, by defining a 4 × 4 projection matrix that we apply after the
model-view matrix. However, we must perform a perspective division at the end. This division can be made a part
of the pipeline, as shown in Figure 4.33.

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