c# - Determine if (x,y,z) point is inside a shape defined by an array of points -

if have array of points (x,y,z) , given single point (x,y,z), code use determine if point resides within shape defined array?

i drawing blank on one...

i'm using c#

edit

thanks responses guys, comments have found link (http://alienryderflex.com/polygon/) explains process quite well.

thanks!

fyi:

bool pointinpolygon() {        int      i, j=polysides-1 ;       boolean  oddnodes=no      ;        (i=0; i<polysides; i++) {         if (polyy[i]<y && polyy[j]>=y         ||  polyy[j]<y && polyy[i]>=y) {           if (polyx[i]+(y-polyy[i])/(polyy[j]-polyy[i])*(polyx[j]-polyx[i])<x) {             oddnodes=!oddnodes; }}         j=i; }        return oddnodes; } 

it'll need work, thats guts of it.

thanks again

use point know outside shape, , check if line point given point passes through surfaces of shape. if passes through odd number of surfaces, given point inside shape.