/**
* Starts a compound shape operation.
*
* Any shape that is defined in terms of other shape operations must use this method, and use Endgroup() to end the definition.
*
* public static DiamondShapeInfo<TCell> MyCustomShape(this DiamondOp<TCell> op)
* {
* return
* BeginGroup()
* .Shape1()
* .Union()
* .Shape2()
* .EndGroup(op);
* }
*
* @since 1.1
*/
public DiamondOp <TCell> BeginGroup()
{
return(DiamondGrid <TCell> .BeginShape());
}