Computer Science 102
                                   Short Program 1
                                 Due 26 January 11:59PM

   For this program the ONLY authorized source of assistance is
   Dr. Westall or the TA's. ANY OTHER DISCUSSION of the program no matter how "high
   level" or "peripheral" (e.g. Have you started/finished it yet?)
   is STRICTLY FORBIDDEN.  Any student who observes improper behavior
   is encouraged to report it to Dr. Westall. Reports that can be
   verified will be rewarded with a 20 point bonus on the assignment for
   the student doing the reporting and an F for the course for the
   student being reported!!

   Adhere to the following programming standards.  Violations will
   lead to deductions.

   (1) no function should be longer than 30 lines code + whitespace.
   (2) the maximum nesting level in any function is ONE
   (3) code lines should not extend beyond column 72
   (4) no more that one statement may be written on a single line
   (5) use reasonably descriptive names for variables and functions
   (6) package all functions into a single source code module named camera.c
   (7) your program should compile without any warnings with gcc -Wall
   (8) indenting should be consistent with logical nesting
   (9) diagnostic / debug prints should be disabled/deleted in
       your submission.

Your mission in this assignment is to complete three functions that belong
to the camera.c file. Begin by copying all the files in

/home/westall/class/102/assns/sp1

to your own sp1 directory.  After that copy your own vector.h to that
directory.  Now read the file main1.c. This contains the main function
for your program.

You will see that it calls three functions that will live in the camera.c
module.

   cam = cam_init(stdin);
   assert(cam != NULL);
   cam_dump(stderr, cam);

   int x, y;
   vec_t dir;
   char buf[20];
   while (fscanf(stdin, "%d %d", &x, &y) == 2)
   {
       cam_getdir(cam, x, y, &dir);
       sprintf(buf, "pix (%3d, %3d) - ", x, y);
       vec_prn(stderr, buf, &dir);
   }

These functions should operate as follows:

cam_init()

   malloc a cam_t structure
   parse the camera definition (SAMPLE input is main1.txt) but
       remember camera attributes may occur in ANY order
   store the input values in the cam_t structure
   make sure your parser aborts on invalid input
   malloc space for the pixmap and store its address in the cam_t
   return the address of the cam_t

cam_dump()

   printout the camera data in the format shown in main1.out

cam_getdir(cam_t *cam, int x, int y, vec_t *dir)

   the vector pointed to by dir should be filled in with a
   unit vector pointing from the viewpoint to the pixel with
   coordinates (x, y)

   Use the world_x = world_size_x * win_x  /  (win_size_x - 1)
   formulation in the computation.


<<<Do NOT turn in any core files, makefiles etc.>>>

You must turn in ALL the files needed to build your program:

 camera.c main1.c  rayfuns.h  ray.h  rayhdrs.h vector.h

Your program should compile correctly when I (or you) enter the
command:

   gcc -g -Wall *.c -lm

It should not generate any warning messages

HOW TO SUBMIT YOUR CODE:

NOTE:  This procedure has NOTHING in common with "handin" nor "sendlab"
Do NOT even TRY to think about how they fit into this procedure because
THEY DON'T!!

1. From any departmental Solaris system ssh to workstation jmw

2. The submission directories lie in the directory

  /local/jmw2/102/sp1

  which is available ONLY IF YOU HAVE LOGGED INTO WORKSTATION jmw.
  Each student has a subdirectory of /local/jmw2/102/sp1. The name
  of your subdirectory is your userid (in the example we will
  assume your id is wjsmith).

3. copy (via the cp command) required file to your subdirectory
   in /local/jmw2/102 /sp1

   For example:
   cp /home/wjsmith/102/sp1/camera.c    /local/jmw2/102/sp1/wjsmith

   Here you would obviously need to replace
   /home/wjsmith/102/sp1/flag.c
   with wherever you have your the program you are trying to submit.

4. Don't modify the permissions on your subdirectory. They are
   set so that ONLY you can access your directory.

----------------

  After you think you have turned your programs in, its a good idea to

  cd /local/jmw2/102/sp1/wjsmith

  and make sure your files are there and they still compile and work correctly.