Guardar mallas 3D en formato binario personalizado

Cargar mallas de archivo y escritura 3D en muestra de programación de formato binario personalizado

El método Accept expuesto por el miembro RootNode en la clase Scene permite visitar cada sub nodo. El fragmento de código a continuación solo permite convertir mallas.

// load a 3D file
Scene scene = Scene.FromFile("test.fbx");
/*
* 3D format demonstration is simple
*
* struct File {
* MeshBlock blocks[];
* };
*
* struct Vertex {
* float x;
* float y;
* float z;
* };
*
* struct Triangle {
* int a;
* int b;
* int c;
* };
*
* struct MeshBlock {
* int numControlPoints;
* int numTriangles;
* Vertex vertices[numControlPoints];
* Triangle faces[numTriangles];
* };
*/
// open file for writing in binary mode
using (var writer = new BinaryWriter(new FileStream("Save3DMeshesInCustomBinaryFormat_out", FileMode.Create, FileAccess.Write)))
{
// visit each descent nodes
scene.RootNode.Accept(delegate(Node node)
{
foreach (Entity entity in node.Entities)
{
// only convert meshes, lights/camera and other stuff will be ignored
if (!(entity is IMeshConvertible))
continue;
Mesh m = ((IMeshConvertible)entity).ToMesh();
var controlPoints = m.ControlPoints;
// triangulate the mesh, so triFaces will only store triangle indices
int[][] triFaces = PolygonModifier.Triangulate(controlPoints, m.Polygons);
// gets the global transform matrix
Matrix4 transform = node.GlobalTransform.TransformMatrix;
// write number of control points and triangle indices
writer.Write(controlPoints.Count);
writer.Write(triFaces.Length);
// write control points
for (int i = 0; i < controlPoints.Count; i++)
{
// calculate the control points in world space and save them to file
var cp = transform * controlPoints[i];
writer.Write((float)cp.x);
writer.Write((float)cp.y);
writer.Write((float)cp.z);
}
// write triangle indices
for (int i = 0; i < triFaces.Length; i++)
{
writer.Write(triFaces[i][0]);
writer.Write(triFaces[i][1]);
writer.Write(triFaces[i][2]);
}
}
return true;
});
}