Circular frame expressed in canvas cells. radius_cols and
radius_rows differ because a character cell is taller than wide.
| Type | Visibility | Attributes | Name | Initial | |||
|---|---|---|---|---|---|---|---|
| integer, | public | :: | center_row | = | 0 | ||
| integer, | public | :: | center_col | = | 0 | ||
| integer, | public | :: | radius_rows | = | 0 | ||
| integer, | public | :: | radius_cols | = | 0 |