/// <summary>
/// Calculates normals for all triangles specifyed by the given parameters.
/// </summary>
/// <param name="startVertex">The vertex index on which to start.</param>
/// <param name="vertexCount">Total count of vertices to be updated.</param>
public void CalculateNormals(int startVertex, int vertexCount)
{
if ((startVertex < 0) || (startVertex >= m_vertices.Count))
{
throw new ArgumentException("startVertex");
}
if (vertexCount + startVertex > m_vertices.Count)
{
throw new ArgumentException("vertexCount");
}
for (int actVertexIndex = startVertex; actVertexIndex < startVertex + vertexCount; actVertexIndex++)
{
// Find all triangles connected to this vertex and get normals from them
Vector3 finalNormalHelper = Vector3.Zero;
Vector3 finalNormalHelper2 = Vector3.Zero;
int normalCount = 0;
int surfaceCount = m_surfaces.Count;
for (int actSurfaceIndex = 0; actSurfaceIndex < surfaceCount; actSurfaceIndex++)
{
VertexStructureSurface actSurface = m_surfaces[actSurfaceIndex];
int triangleCount = actSurface.CountTriangles;
for (int loopTriangle = 0; loopTriangle < triangleCount; loopTriangle++)
{
int triangleStartIndex = loopTriangle * 3;
if ((actSurface.IndicesInternal[triangleStartIndex] == actVertexIndex) ||
(actSurface.IndicesInternal[triangleStartIndex + 1] == actVertexIndex) ||
(actSurface.IndicesInternal[triangleStartIndex + 2] == actVertexIndex))
{
Vertex v1 = m_vertices[actSurface.IndicesInternal[triangleStartIndex]];
Vertex v2 = m_vertices[actSurface.IndicesInternal[triangleStartIndex + 1]];
Vertex v3 = m_vertices[actSurface.IndicesInternal[triangleStartIndex + 2]];
finalNormalHelper += Vector3Ex.CalculateTriangleNormal(v1.Geometry.Position, v2.Geometry.Position, v3.Geometry.Position, false);
normalCount++;
}
}
}
// Calculate final normal
if (normalCount > 0)
{
Vertex actVertex = m_vertices[actVertexIndex];
actVertex.Normal = finalNormalHelper / finalNormalHelper.Length();
m_vertices[actVertexIndex] = actVertex;
normalCount = 0;
}
}
}
/// <summary>
/// Calculates normals for the given treangle.
/// </summary>
/// <param name="actTriangle">The triangle for which to calculate the normal (flat).</param>
public void CalculateNormalsFlat(Triangle actTriangle)
{
var v1 = m_owner.RawGeometry[actTriangle.Index1];
var v2 = m_owner.RawGeometry[actTriangle.Index2];
var v3 = m_owner.RawGeometry[actTriangle.Index3];
Vector3 normal = Vector3Ex.CalculateTriangleNormal(v1.Position, v2.Position, v3.Position);
v1 = v1.Copy(v1.Position, normal);
v2 = v2.Copy(v2.Position, normal);
v3 = v3.Copy(v3.Position, normal);
m_owner.RawGeometry[actTriangle.Index1] = v1;
m_owner.RawGeometry[actTriangle.Index2] = v2;
m_owner.RawGeometry[actTriangle.Index3] = v3;
}
/// <summary>
/// Calculates normals for the given treangle.
/// </summary>
/// <param name="actTriangle">The triangle for which to calculate the normal (flat).</param>
public void CalculateNormalsFlat(Triangle actTriangle)
{
Vertex v1 = m_owner.VerticesInternal[actTriangle.Index1];
Vertex v2 = m_owner.VerticesInternal[actTriangle.Index2];
Vertex v3 = m_owner.VerticesInternal[actTriangle.Index3];
Vector3 normal = Vector3Ex.CalculateTriangleNormal(v1.Geometry.Position, v2.Geometry.Position, v3.Geometry.Position);
v1 = v1.Copy(v1.Geometry.Position, normal);
v2 = v2.Copy(v2.Geometry.Position, normal);
v3 = v3.Copy(v3.Geometry.Position, normal);
m_owner.VerticesInternal[actTriangle.Index1] = v1;
m_owner.VerticesInternal[actTriangle.Index2] = v2;
m_owner.VerticesInternal[actTriangle.Index3] = v3;
}
