/*

	This example demonstrates how to set and use the turn edge offset.

*/

NewScene( null, false );

CreatePrim("Grid", "MeshSurface", null, null);

SetValue("grid.polymsh.geom.subdivu", 2, null);

SetValue("grid.polymsh.geom.subdivv", 2, null);

var GridGeom = GetValue( "Grid" ).ActivePrimitive.Geometry;

var Polygons = GridGeom.Polygons;

var Polygon = Polygons.Item(3);

var PolygonVertices = Polygon.Vertices;

var TriangleSubIndices = Polygon.TriangleSubIndexArray.toArray();

Application.LogMessage( "Polygon #3 is defined with the following vertices: " + 

						PolygonVertices.Item(0).Index + ", " + 

						PolygonVertices.Item(1).Index + ", " + 

						PolygonVertices.Item(2).Index + ", " + 

						PolygonVertices.Item(3).Index );

Application.LogMessage( "Polygon #3 has the following two triangles before applying the TurnEdge operator: [" + 

						PolygonVertices.Item(TriangleSubIndices[0]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[1]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[2]).Index + "] and [" +

						PolygonVertices.Item(TriangleSubIndices[3]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[4]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[5]).Index + "]." );

ApplyOp("TurnEdgeOp", "grid.poly[LAST]", 3, siPersistentOperation, null, 0);

var GridGeom = GetValue( "Grid" ).ActivePrimitive.Geometry;

var Polygons = GridGeom.Polygons;

var Polygon = Polygons.Item(3);

var PolygonVertices = Polygon.Vertices;

var TriangleSubIndices = Polygon.TriangleSubIndexArray.toArray();

Application.LogMessage( "Polygon #3 has the following two triangles after applying the TurnEdge operator: [" + 

						PolygonVertices.Item(TriangleSubIndices[0]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[1]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[2]).Index + "] and [" +

						PolygonVertices.Item(TriangleSubIndices[3]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[4]).Index + ", " +

						PolygonVertices.Item(TriangleSubIndices[5]).Index + "]" );

var offset = Polygon.TurnInternalEdgeOffset; // this should be 1 since with only turned the polygon edges once.

Application.LogMessage( "This triangulation is equivalent to that of a polygon defined using the following vertices: " + 

						PolygonVertices.Item( ( 0 + offset ) % 4 ).Index + ", " + 

						PolygonVertices.Item( ( 1 + offset ) % 4 ).Index + ", " + 

						PolygonVertices.Item( ( 2 + offset ) % 4 ).Index + ", " + 

						PolygonVertices.Item( ( 3 + offset ) % 4 ).Index );

// Expected results:

// INFO : Polygon #3 is defined with the following vertices: 4, 5, 8, 7

// INFO : Polygon #3 has the following two triangles before applying the TurnEdge operator: [4, 5, 8] and [4, 8, 7].

// INFO : Polygon #3 has the following two triangles after applying the TurnEdge operator: [5, 8, 7] and [5, 7, 4]

// INFO : This triangulation is equivalent to that of a polygon defined using the following vertices: 5, 8, 7, 4