private void WireframeHelper(GeometryModel3D model, Matrix3DStack matrixStack)
{
var geometry = model.Geometry;
var mesh = geometry as MeshGeometry3D;
if (mesh == null)
{
return;
}
var positions = new Point3D[mesh.Positions.Count];
mesh.Positions.CopyTo(positions, 0);
matrixStack.Peek().Transform(positions);
var indices = mesh.TriangleIndices;
if (indices.Count > 0)
{
var limit = positions.Length - 1;
for (int i = 2, count = indices.Count; i < count; i += 3)
{
var i0 = indices[i - 2];
var i1 = indices[i - 1];
var i2 = indices[i];
// WPF halts rendering on the first deformed triangle. We should
// do the same.
if ((0 > i0 || i0 > limit) ||
(0 > i1 || i1 > limit) ||
(0 > i2 || i2 > limit))
{
break;
}
AddTriangle(positions, i0, i1, i2);
}
}
else
{
for (int i = 2, count = positions.Length; i < count; i += 3)
{
var i0 = i - 2;
var i1 = i - 1;
var i2 = i;
AddTriangle(positions, i0, i1, i2);
}
}
}
