public DescriptionCourseObj(Id<Special> specialId, PointF topLeft, float cellSize, SymbolDB symbolDB, DescriptionLine[] description, DescriptionKind kind, int numColumns)
: base(Id<ControlPoint>.None, Id<CourseControl>.None, specialId, 1, new CourseAppearance(), GetRect(topLeft, cellSize, symbolDB, description, kind, numColumns))
{
// Create the renderer.
renderer = new DescriptionRenderer(symbolDB);
renderer.Description = description;
renderer.DescriptionKind = kind;
renderer.Margin = cellSize / 20; // about the thickness of the thick lines.
renderer.CellSize = cellSize;
renderer.NumberOfColumns = numColumns;
aspectAnglesByColumns = ComputeAspectAngles();
}