# Homework 1, due **Wed** Sep 9, 2009

Hand in during lab, or email PDF file to Kalyana.

- As described in Angel, what are the 4 major components of a 3D graphics API?
- As described in Angel, what are the 4 stages of the graphics pipeline?
- Find the eigenvalues and eigenvectors of the following matrix. Suggested tools include Matlab, Maple, or doing it by hand. {$ \left(\begin{array} .8 & .6\\-.6 & .8 \end{array}\right) $}
- Consider these 3-D vectors: A=(1,2,3), B=(5,4,6), C=(7,8,9). Compute:
- A.BxC
- AxB.C

*(This is another a test of your linear algebra knowledge. Feel free to refer to books to find the correct formulae.)*Suppose that we have a plane in 3-D thru the points A(2,0,2), B(2,2,0), and C(0,1,1).- What is its equation, in the form
*ax+by+cz+d=0*? - Consider the line L thru the points O(0,0,0) and P(1,1,1). Where does this line intersect the plane?

- What is its equation, in the form
- This is a test of whether you know enough C for this course.
The following code will copy string
**s**to array**t**, provided that a few erroneous lines are corrected. What are the corrections and proper initializations?char *s="Hello!"; char t[6]; char p, q; p=s; q=t; for (;*q++ = *p++;);

- If we're going to be learning complicated graphics in this course, it behooves us still to be able to do the simple things. So, this exercise is to plot the ship NCC1701 similarly to the plot shown in the right margin.

Here is a compressed file of 3,958
triangles defining the USS Enterprise. It looks like the
image on the right
when uncompressed with *gunzip*:

1.431000 0.505000 0.843000 1.572000 0.505000 0.801000 1.287000 0.505000 0.802000 1.431000 0.505000 0.843000 1.572000 0.505000 0.801000 1.595000 0.542000 0.794000 1.263000 0.542000 0.795000 1.572000 0.505000 0.801000 1.572000 0.505000 0.801000 1.263000 0.542000 0.795000 1.287000 0.505000 0.802000 1.572000 0.505000 0.801000 ... and similarly for 23730 more lines

Each line of the file represents one vertex in the form:
(*x*, *y*, *z*). Four lines make one triangle; the first vertex is
repeated. Two blank lines separate each triangle.

You may want to cut off a piece of the file for testing. This is how to do that in Linux.

head -1000 /tmp/ncc > /tmp/piece

Plot the data. I used *gnuplot*; you may use whatever you
like. It's ok to render it as polygons if you wish. You
don't need to delete hidden lines, i.e., don't over-engineer
the plot.