Before I replaced these slides with a few fixes, AugustSZ commented —
There're 2 kinds of projections mentioned in Fundamentals of Computer Graphics: Orthographic Projection and Perspective projection. Camera Definition: position, orientation(up/look-at)

I replied —
Yes, that's right. We'll have a closer look when we get to the Perspective Projection lecture on Feb 9th. We've made an assumption here that we have Perspective projection, with camera position at c (really, c=(0,0,0) given the math on the slide), up vector is y, and look-at vector is z. If we want a general camera, we'll need to loosen those restrictions later to allow arbitrary camera positions and orientations. However, you can always fall back on the rule of similar triangles. They may be oriented oddly in 3D space to begin with, but we'll see how to transform them to look like the picture above.

Orthographic projection is very simple. For orthographic projection in the picture above, v=y and u=x. Nothing more to do.

Before I replaced these slides with a few fixes, AugustSZ commented — There're 2 kinds of projections mentioned in Fundamentals of Computer Graphics: Orthographic Projection and Perspective projection. Camera Definition: position, orientation(up/look-at)

I replied — Yes, that's right. We'll have a closer look when we get to the Perspective Projection lecture on Feb 9th. We've made an assumption here that we have Perspective projection, with camera position at c (really, c=(0,0,0) given the math on the slide), up vector is y, and look-at vector is z. If we want a general camera, we'll need to loosen those restrictions later to allow arbitrary camera positions and orientations. However, you can always fall back on the rule of similar triangles. They may be oriented oddly in 3D space to begin with, but we'll see how to transform them to look like the picture above.

Orthographic projection is very simple. For orthographic projection in the picture above, v=y and u=x. Nothing more to do.