|   | Name | Type | Identifier | Description | Constraints | 
| Input | Elevation | Grid (input) | ELEVATION | - | - | 
| Output | Visibility | Grid (output) | VISIBILITY | - | - | 
| Options | Grid System | Grid system | PARAMETERS_GRID_SYSTEM | - | - | 
 | Height | Floating point | HEIGHT | Height of the light source above ground. | Default: 100.000000 | 
 | Unit | Choice | METHOD | - | Available Choices: [0] Visibility [1] Shade [2] Distance [3] Size Default: 1 | 
 | Multiple Observer | Boolean | MULTIPLE_OBS | Allow multiple observer positions. | Default: 0 |