public void CalculateTangents()
{
Disposer.Dispose(Tangents);
Tangents = new Vector3Buffer(Vertices.Length);
for (int i = 0; i < Vertices.Length; i += 3)
{
Vector3 v1 = Vertices[i + 0];
Vector3 v2 = Vertices[i + 1];
Vector3 v3 = Vertices[i + 2];
Vector2 w1 = TexCoords[i + 0];
Vector2 w2 = TexCoords[i + 1];
Vector2 w3 = TexCoords[i + 2];
float x1 = v2.X - v1.X;
float x2 = v3.X - v1.X;
float y1 = v2.Y - v1.Y;
float y2 = v3.Y - v1.Y;
float z1 = v2.Z - v1.Z;
float z2 = v3.Z - v1.Z;
float s1 = w2.X - w1.X;
float s2 = w3.X - w1.X;
float t1 = w2.Y - w1.Y;
float t2 = w3.Y - w1.Y;
float r = 1.0f / (s1 * t2 - s2 * t1);
Vector3 sdir = new Vector3((t2 * x1 - t1 * x2) * r, (t2 * y1 - t1 * y2) * r, (t2 * z1 - t1 * z2) * r);
Vector3 tdir = new Vector3((s1 * x2 - s2 * x1) * r, (s1 * y2 - s2 * y1) * r, (s1 * z2 - s2 * z1) * r);
Tangents[i + 0] = sdir;
Tangents[i + 1] = sdir;
Tangents[i + 2] = sdir;
}
for (int a = 0; a < Vertices.Length; a++)
{
Vector3 n = Normals[a];
Vector3 t = Tangents[a];
// Gram-Schmidt orthogonalize
Tangents[a] = Vector3.Normalize((t - n * Vector3.Dot(n, t)));
// Calculate handedness
//tangents[a].w = (dot(cross(n, t), bitangents[a]) < 0.0F) ? -1.0F : 1.0F;
}
}
public void FromStream(BinaryReader reader)
{
if (reader == null)
{
throw new ArgumentNullException("reader");
}
if (reader.ReadBoolean())
{
Vertices = new Vector3Buffer(reader);
}
if (reader.ReadBoolean())
{
Tangents = new Vector3Buffer(reader);
}
if (reader.ReadBoolean())
{
Colors = new Vector3Buffer(reader);
}
if (reader.ReadBoolean())
{
Normals = new Vector3Buffer(reader);
}
if (reader.ReadBoolean())
{
TexCoords = new Vector2Buffer(reader);
}
if (reader.ReadBoolean())
{
Indices = new UInt32Buffer(reader);
}
Type = (PrimitiveType)reader.ReadUInt32();
DrawStyle = (PolygonMode)reader.ReadUInt32();
FrontFace = (FrontFaceDirection)reader.ReadUInt32();
Name = reader.ReadNullbaleString();
var boundsCenter = reader.ReadVector3();
var boundsSize = reader.ReadVector3();
var boundsRadius = reader.ReadSingle();
Bounds = new BoundingVolume(boundsCenter, boundsSize, boundsRadius);
}
public void CalculateNormals()
{
Disposer.Dispose(ref _normals);
_normals = new Vector3Buffer(_vertices.Length);
if (Indices != null)
{
var normalsList = new List <Vector3> [_vertices.Length];
var indices = Indices;
for (int i = 0; i < indices.Length; i++)
{
Int32 pindex = (Int32)indices[i];
Int32 aindex, bindex;
switch (i % 3)
{
case 0:
aindex = (Int32)indices[i + 1];
bindex = (Int32)indices[i + 2];
break;
case 1:
aindex = (Int32)indices[i + 1];
bindex = (Int32)indices[i - 1];
break;
case 2:
aindex = (Int32)indices[i - 2];
bindex = (Int32)indices[i - 1];
break;
default:
throw new ArithmeticException();
}
var vertexNormals = normalsList[pindex];
if (vertexNormals == null)
{
vertexNormals = normalsList[pindex] = new List <Vector3>(1);
}
var p = _vertices[pindex];
var a = _vertices[aindex];
var b = _vertices[bindex];
var normal = Vector3.Cross(a - p, b - p).Normalized;
vertexNormals.Add(normal);
}
for (int i = 0; i < _vertices.Length; i++)
{
_normals[i] = normalsList[i]
.Sum()
.Normalized;
}
}
else
{
for (int i = 0; i < _vertices.Length; i++)
{
var pindex = i;
int aindex, bindex;
switch (i % 3)
{
case 0:
aindex = i + 1;
bindex = i + 2;
break;
case 1:
aindex = i + 1;
bindex = i - 1;
break;
case 2:
aindex = i - 2;
bindex = i - 1;
break;
default:
throw new ArithmeticException();
}
var p = _vertices[pindex];
var a = _vertices[aindex];
var b = _vertices[bindex];
_normals[i] = Vector3
.Cross(a - p, b - p)
.Normalized;
}
}
}
