[comp.graphics] COMPLICATED PROBLEM

rrr@naucse.UUCP (Bob Rose ) (03/02/88)

In article <3320@bloom-beacon.MIT.EDU>, tada@athena.mit.edu (Michael Zehr) writes:
>> [Someones algo for finding if a point is inside a poly]
> The method I use in some graphics programs requires a compare and an
> xor for each edge of the polygon, and 2 multiplies (total, not for each
> edge).
> michael j zehr


Sounds interesting. Lets here about the algorithm, it does sound
rather specific though, like xor is not that common in (none bit mask)
graphic routines.

                                  -bob

Robert R. Rose
Northern Arizona University, Box 15600
Flagstaff, AZ 86011
                    .....!ihnp4!arizona!naucse!rrr

gil@icus.UUCP (Gil Kloepfer Jr.) (03/06/88)

Keywords: READ THIS ONLY IF YOUR IQ >>125

In article <590@naucse.UUCP> rrr@naucse.UUCP writes:
>Sounds interesting. Lets here about the algorithm, it does sound
>rather specific though, like xor is not that common in (none bit mask)
>graphic routines.
>
>                                  -bob
>
>Robert R. Rose
>Northern Arizona University, Box 15600
>Flagstaff, AZ 86011
>                    .....!ihnp4!arizona!naucse!rrr

A book which may be of some interest is a book called "Collected
Algorithims" by David Douglas.  I believe the book comes out of the
Harvard graphics/geographic systems lab somehow.  I know I have seen
the book .. and it contains some very interesting algs of this nature.

Also interesting is a paperback book entitled _A_Programmer's_Geometry_
(I forgot the author) which has a wealth of information about geometric
routines used often in computer graphics.

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