3D "VECTOR"-OBJECT ROUTINE FOR TURBO PASCAL 5.5 (SOURCE)
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This is a 3D intro originally intended for my PD version of COLORIS, which
will be coming your way shortly.  To run it, be sure to compile the two units
first.  These contain the object definitions, my own homemade cosinus and
tangiens tables and some other necessary stuff.
   My first attempts at making 3D graphics used Turbo Pascals own trig-
procedures, but I found these to be too slow.  My routines are a bit faster,
but are not as accurate.  Also, there's still some bugs in there which I'm
going to have to remove.  One of them is in my tangiens routine.  - As you
all probably know, Tan=Sin/Cos.  This means that Cos can't be allowed to be
zero... This, however, is a small fault, and when rotating the objects
"cleverly", you can get around this problem.  What I can't understand, though,
is why the objects start to "shake" when I rotate them around all the three
axes simultaneously.
   If you want to check out this phenomena for yourself, locate one of the
procedures named "Letter1" to "Letter7" in the main program.  You'll find that
I use a command called "Rotate".  This takes 3 parameters: First the two axes
it's to modify the coordinates for (the two axes the object is NOT rotating
around), and secondly the rotation, which is a positive size between 0 and
360.  Now try inserting a third Rotate statement, rotating the object around
the last axis.

If you've got any comments or questions about this source or about Turbo
Pascal in general, contact me at at this BBS...

Bjrn Wang
