Polygons, Shapes

[Pete]

Whats the easiest way of defining a shape
and knowing if a point is with in it?

parden the crude pseduocode...
i want something like:

Shape1 = p1,p2,p3,p4,p5, p6,p7,p8,p9,p10

pnt = x,y

if (shape1 containes(pnt)) {

}

Anyone know of something like this?

Pete

[Alf P. Steinbach]

On Wed, 27 Aug 2003 23:04:32 GMT, "Pete" <p_*********@co mcast.net> wrote:

Whats the easiest way of defining a shape
Try using a std::vector for the points.

and knowing if a point is with in it?

parden the crude pseduocode...
i want something like:

Shape1 = p1,p2,p3,p4,p5, p6,p7,p8,p9,p10

pnt = x,y

if (shape1 containes(pnt)) {

}

Anyone know of something like this?

What's the C++ question?

<ot>
E.g. count the number of crossing for a line through the point, or
walk the perimeter of the shape and check the direction to the point.
</ot>

[Peter Ammon]

Pete wrote:

Whats the easiest way of defining a shape
and knowing if a point is with in it?

parden the crude pseduocode...
i want something like:

Shape1 = p1,p2,p3,p4,p5, p6,p7,p8,p9,p10

pnt = x,y

if (shape1 containes(pnt)) {

}

Anyone know of something like this?

Pete

This is question 2.03 of the comp.graphics.a lgorithms FAQ.

http://www.exaflop.org/docs/cgafaq/ind.html

-Peter