OpenSim-Test/OpenSim/Region/Terrain.BasicTerrain/libTerrainBSD/Channel/Neighbours.cs

/*
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 * See CONTRIBUTORS.TXT for a full list of copyright holders.
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 * modification, are permitted provided that the following conditions are met:
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 *       derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
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 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

namespace libTerrain
{
    partial class Channel
    {
        private enum NeighbourSystem
        {
            Moore,
            VonNeumann
        } ;

        private int[] Neighbours(NeighbourSystem type, int index)
        {
            int[] coord = new int[2];

            index++;

            switch (type)
            {
                case NeighbourSystem.Moore:
                    switch (index)
                    {
                        case 1:
                            coord[0] = -1;
                            coord[1] = -1;
                            break;

                        case 2:
                            coord[0] = -0;
                            coord[1] = -1;
                            break;

                        case 3:
                            coord[0] = +1;
                            coord[1] = -1;
                            break;

                        case 4:
                            coord[0] = -1;
                            coord[1] = -0;
                            break;

                        case 5:
                            coord[0] = -0;
                            coord[1] = -0;
                            break;

                        case 6:
                            coord[0] = +1;
                            coord[1] = -0;
                            break;

                        case 7:
                            coord[0] = -1;
                            coord[1] = +1;
                            break;

                        case 8:
                            coord[0] = -0;
                            coord[1] = +1;
                            break;

                        case 9:
                            coord[0] = +1;
                            coord[1] = +1;
                            break;

                        default:
                            break;
                    }
                    break;

                case NeighbourSystem.VonNeumann:
                    switch (index)
                    {
                        case 1:
                            coord[0] = 0;
                            coord[1] = -1;
                            break;

                        case 2:
                            coord[0] = -1;
                            coord[1] = 0;
                            break;

                        case 3:
                            coord[0] = +1;
                            coord[1] = 0;
                            break;

                        case 4:
                            coord[0] = 0;
                            coord[1] = +1;
                            break;

                        case 5:
                            coord[0] = -0;
                            coord[1] = -0;
                            break;

                        default:
                            break;
                    }
                    break;
            }

            return coord;
        }
    }
}