private void SelectTriangle(int triangleIndex)
{
if (_selectedTriangleIndex == triangleIndex)
{
return;
}
_isSelectionChangedInternally = true;
OverlayCanvas.Children.Clear();
if (triangleIndex >= 0)
{
OverviewListBox.SelectedIndex = triangleIndex;
OverviewListBox.ScrollIntoView(OverviewListBox.Items[triangleIndex]);
OverviewListBox.Focus(); // Without calling focus the blue selection is not visible
int i = triangleIndex * 3;
Point3D p1, p2, p3;
int index1 = _rootMesh.TriangleIndices[i];
int index2 = _rootMesh.TriangleIndices[i + 1];
int index3 = _rootMesh.TriangleIndices[i + 2];
p1 = _rootMesh.Positions[index1];
p2 = _rootMesh.Positions[index2];
p3 = _rootMesh.Positions[index3];
if (_rootMesh.Normals != null && _rootMesh.Normals.Count == _rootMesh.Positions.Count)
{
// we can offset the Polyline so it will not be fighting for Z-depth with the object
// This way the selection lines will be drawn on top of the selected object
Vector3D n1 = _rootMesh.Normals[index1];
n1.Normalize();
Vector3D n2 = _rootMesh.Normals[index2];
n2.Normalize();
Vector3D n3 = _rootMesh.Normals[index2];
n3.Normalize();
p1 += n1 * _selectedTriangleOffset;
p2 += n2 * _selectedTriangleOffset;
p3 += n3 * _selectedTriangleOffset;
}
SelectedTrianglePolyline.Positions = new Point3DCollection(new Point3D[] { p1, p2, p3 });
SelectedTrianglePolyline.IsVisible = true;
if (ShowSelectedIndexesCheckBox.IsChecked ?? false)
{
AddPositionIndexTextBlocks(i);
}
}
else
{
OverviewListBox.SelectedIndex = -1;
SelectedTrianglePolyline.IsVisible = false;
}
_isSelectionChangedInternally = false;
_selectedTriangleIndex = triangleIndex;
}
