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);
}