A static class that holds pointer ID values.
These values are used as the values for IPointerEvent.pointerId.
| invalidPointerId | Represents an invalid pointer ID value. | 
| maxPointers | The maximum number of pointers the implementation supports. | 
| mousePointerId | The mouse pointer ID. | 
| penPointerCount | The number of pen pointers the implementation supports. | 
| penPointerIdBase | The base ID for pen pointers. | 
| touchPointerCount | The number of touch pointers the implementation supports. | 
| touchPointerIdBase | The base ID for touch pointers. |