/** * Generate a triagle mesh for the hexagon */ public ITriangleMesh GenerateMesh() { ITriangleMesh mesh = new TriangleMesh(); Vector2[] texCoords = new Vector2[7]; Vector2 texCoordCenter = new Vector2(0.2f, 0.2f); for (int i = 0; i < 6; i++) { Vector3 v = GetCorner(i); mesh.AddVertex(v); texCoords[i] = getTexCoord(0.2f, texCoordCenter, i); } mesh.AddVertex(pos); texCoords[6] = texCoordCenter; int texCoordStartIndex = mesh.GetNumberOfTexCoords(); for (int i = 0; i < 7; i++) { mesh.AddTextureCoordinate(texCoords[i]); } for (int i = 0; i < 6; i++) { Triangle t = new Triangle(i, 6, (i + 1) % 6, texCoordStartIndex + i, texCoordStartIndex + 6, texCoordStartIndex + (i + 1) % 6); mesh.AddTriangle(t); } mesh.ComputeTriangleNormals(); return(mesh); }
public static ITriangleMesh Snap(ITriangleMesh mesh, float epsilon) { Dictionary <int, int> vertexMapping = new Dictionary <int, int>(); ITriangleMesh result = new TriangleMesh(); for (int i = 0; i < mesh.GetNumberOfVertices(); i++) { Vector3 vi = mesh.GetVertex(i); bool found = false; for (int j = 0; j < result.GetNumberOfVertices(); j++) { Vector3 vj = result.GetVertex(j); if (Vector3.Subtract(vi, vj).Length < epsilon) { vertexMapping[i] = j; found = true; } } if (!found) { int idx = result.AddVertex(vi); vertexMapping[i] = idx; } } for (int i = 0; i < mesh.GetNumberOfTexCoords(); i++) { result.AddTextureCoordinate(mesh.GetTextureCoordinate(i)); } for (int i = 0; i < mesh.GetNumberOfTriangles(); i++) { Triangle t = mesh.GetTriangle(i).Clone(); t.A = vertexMapping[t.A]; t.B = vertexMapping[t.B]; t.C = vertexMapping[t.C]; result.AddTriangle(t); } Console.WriteLine("Mesh snapping: " + mesh.GetNumberOfVertices() + " -> " + result.GetNumberOfVertices() + " verts."); return(result); }
private ITriangleMesh CreateBoundary(ITriangleMesh mesh, float height, float borderHeightTop, float borderHeightBottom, Vector3 offset, Vector2[] cornerTexCoords) { List <TriangleEdge> border = mesh.GetBorder(); int vertsPerBorderEdge = 3; ITriangleMesh borderMesh = new TriangleMesh(); for (int i = 0; i < border.Count; i++) { borderMesh.AddVertex(mesh.GetVertex(border[i].A)); } for (int i = 0; i < border.Count; i++) { TriangleEdge borderEdge = border[i]; TriangleEdge prevEdge = border[(i + border.Count - 1) % border.Count]; Vector3 v = borderMesh.GetVertex(i); // v0 Vector3 edgeNormal = ComputeBorderEdgeNormal(borderEdge, mesh); Vector3 prevEdgeNormal = ComputeBorderEdgeNormal(prevEdge, mesh); Vector3 borderNormal = Vector3.Add(edgeNormal, prevEdgeNormal); borderNormal.Normalize(); borderNormal = Vector3.Multiply(borderNormal, Math.Max(borderHeightTop, borderHeightBottom) / (float)Math.Sin(30.0 / 180.0 * Math.PI)); Vector3 v0 = Vector3.Add(Vector3.Add(v, borderNormal), new Vector3(0, 0, -borderHeightTop)); borderMesh.AddVertex(v0); // v1 Vector3 v1 = Vector3.Add(v0, Vector3.Multiply(Vector3.UnitZ, -(height - (borderHeightTop + borderHeightBottom)))); borderMesh.AddVertex(v1); // v2 Vector3 v2 = Vector3.Add(v, Vector3.Multiply(Vector3.UnitZ, -height)); borderMesh.AddVertex(v2); } float alpha = (float)(borderHeightTop * Math.Sqrt(2) / (borderHeightTop * Math.Sqrt(2) + borderHeightBottom * Math.Sqrt(2) + height)); float beta = 1 - (float)(borderHeightBottom * Math.Sqrt(2) / (borderHeightTop * Math.Sqrt(2) + borderHeightBottom * Math.Sqrt(2) + height)); int ti0 = borderMesh.AddTextureCoordinate(cornerTexCoords[0]); int ti1 = borderMesh.AddTextureCoordinate(Vector2.Add(Vector2.Multiply(cornerTexCoords[0], 1 - alpha), Vector2.Multiply(cornerTexCoords[1], alpha))); int ti2 = borderMesh.AddTextureCoordinate(Vector2.Add(Vector2.Multiply(cornerTexCoords[0], 1 - beta), Vector2.Multiply(cornerTexCoords[1], beta))); int ti3 = borderMesh.AddTextureCoordinate(cornerTexCoords[1]); int ti_0 = borderMesh.AddTextureCoordinate(cornerTexCoords[2]); int ti_1 = borderMesh.AddTextureCoordinate(Vector2.Add(Vector2.Multiply(cornerTexCoords[2], 1 - alpha), Vector2.Multiply(cornerTexCoords[3], alpha))); int ti_2 = borderMesh.AddTextureCoordinate(Vector2.Add(Vector2.Multiply(cornerTexCoords[2], 1 - beta), Vector2.Multiply(cornerTexCoords[3], beta))); int ti_3 = borderMesh.AddTextureCoordinate(cornerTexCoords[3]); // Triangles for (int i = 0; i < border.Count; i++) { TriangleEdge borderEdge = border[i]; int vi0 = border.Count + vertsPerBorderEdge * i + 0; int vi1 = border.Count + vertsPerBorderEdge * i + 1; int vi2 = border.Count + vertsPerBorderEdge * i + 2; int vi_0 = border.Count + vertsPerBorderEdge * ((i + 1) % border.Count) + 0; int vi_1 = border.Count + vertsPerBorderEdge * ((i + 1) % border.Count) + 1; int vi_2 = border.Count + vertsPerBorderEdge * ((i + 1) % border.Count) + 2; // A Triangle t = new Triangle(i, vi0, (i + 1) % border.Count, ti0, ti1, ti_1); borderMesh.AddTriangle(t); // B t = new Triangle((i + 1) % border.Count, vi0, vi_0, ti_0, ti1, ti_1); borderMesh.AddTriangle(t); // C t = new Triangle(vi0, vi1, vi_0, ti1, ti2, ti_1); borderMesh.AddTriangle(t); // D t = new Triangle(vi1, vi_1, vi_0, ti2, ti_2, ti_1); borderMesh.AddTriangle(t); // E t = new Triangle(vi1, vi2, vi_1, ti2, ti3, ti_2); borderMesh.AddTriangle(t); // F t = new Triangle(vi2, vi_2, vi_1, ti3, ti_3, ti_2); borderMesh.AddTriangle(t); } return(borderMesh); }