Talk:IsPointInPolygon2D

Very nice, would be superb if the creator could put it under the geometric library, but I am not putting anyone under pressure to do so. Just would be better in my honest opinion if all these useful functions would be put under a general heading instead of splattered into their own pages. --Nexii Malthus 16:11, 18 August 2008 (PDT)

It can be included but not until it has been properly attributed and the license fulfilled. It is an illegal (since the licensing restriction were ignored) port of PNPOLY. I've written a new port from the original C code, I just haven't tested it yet.

<lsl>//Copyright (c) 1970-2003, Wm. Randolph Franklin //Copyright (c) 2008, Strife Onizuka (porting to LSL) // //Permission is hereby granted, free of charge, to any person obtaining a copy //of this software and associated documentation files (the "Software"), to deal //in the Software without restriction, including without limitation the rights //to use, copy, modify, merge, publish, distribute, sublicense, and/or sell //copies of the Software, and to permit persons to whom the Software is //furnished to do so, subject to the following conditions: // // 1. Redistributions of source code must retain the above copyright notice, // this list of conditions and the following disclaimers. // 2. Redistributions in binary form must reproduce the above copyright // notice in the documentation and/or other materials provided with the // distribution. // 3. The name of W. Randolph Franklin may not be used to endorse or promote // products derived from this Software without specific prior written // permission.

//THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR //IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, //FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE //AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER //LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, //OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE //SOFTWARE.

integer isPointInPolygon2D(list vertx, list verty, float testx, float testy) {//Copyright (c) 1970-2003, Wm. Randolph Franklin; 2008, Strife Onizuka

   integer i = ~(polygon != []);
   integer c = 0;
   if(i < -2)
   {
       float vxi = llList2Float(vertx, -1);
       float vyi = llList2Float(verty, -1);
       float vyj;
       do{
           float vxj = vxi;
           vxi = llList2Float(vertx, i);
           if(((vyi = llList2Float(verty, i)) > testy) ^ ((vyj = vyi) > testy))
           {
               if(vyj != vyi)
                   c = c ^ (testx < (((vxj - vxi) * (testy - vyi) / (vyj - vyi)) + vxi));
               else//working around lack of infinity in LSL
                   c = c ^ (0 < ((vxj-vxi) * (testy-vyi)));
           }
       }while (++i < nvert);
   }
   return c;

}

integer isPointInPolygon2D(list vert, vector test) {//Copyright (c) 1970-2003, Wm. Randolph Franklin; 2008, Strife Onizuka

   integer i = ~(polygon != []);
   integer c = 0;
   if(i < -2)
   {
       vector vi = llList2Vector(vert, -1);
       do {
           vector vj = vi;
           vi = llList2Vector(vert, i);
           if((vi.y > test.y) ^ (vj.y > test.y))
           {
               if(vj.y != vi.y)
                   c = c ^ (test.x < (((vj.x - vi.x) * (test.y - vi.y) / (vj.y - vi.y)) + vi.x));
               else//working around lack of infinity in LSL
                   c = c ^ (0 < ((vj.x-vi.x) * (test.y-vi.y)));
           }
       } while (++i < nvert);
   }
   return c;

}</lsl>