[Cst-1b] 99.6.4 Graphics

[Nathan Dimmock]

"M.Y.W.Y.B." wrote:
> 
> CST 99.6.4 Graphics
> 
> First Part (rotate the cone)
> 
> I'm not sure whether the values are correct. Could someone check against
> his/her values?
> 
> 1) Scale: 4*x, 4*y, 13*z

It's actually 8 units in the x and y directions - IIRC the one part of
the question says diameter and the other one says radius.

> 2) Rotate about y-axis by -13.33 degrees
> 3) Rotate about x-axis by 22.62 degrees

I then did rotate about y-axis by 22.62 degrees then about z-axis by
76.66 degrees, which is correct according to my supervisor!  OTOH, there
may be more than one way of doing it!

(hmm.. just noticed my values are similar to yours except in a different
order and direction around different axes - wouldn't surprise me if you
are correct too!)

> 4) Translage: x -1, y +3, z +7
> 
> Last Part:
> Clearly the Sutherland algorithm doesn't work with concave clipping poly's.
> What to do?
> Break it into smaller, convex poly's?

Yep

-- 
Nathan 
Jesus College, Cambridge, CB5 8BL
http://www-jcsu.jesus.cam.ac.uk/~ned21/