LEGION Model Builder Help

To draw a visibility-based Analysis Zone for a point

  1. Click the visibility drawing icon (any icons and features not connected with visibility drawing are disabled).
  2. Click the Analysis Zone icon .

    You are prompted to select 'Visibility for Point or Segment? [P]/S'

  3. For a point, hit Return.
  4. Click to place the visibility point. Choose the point whose visibility you want the Analysis Zone to calculate and model. This should be the centre of the object (camera, small sign, etc.). Use the pan and zoom tools as normal if required.
    Note: You can only place your point inside the model's accessible space. A dotted line is temporarily imposed on the model, delineating areas of accessible space.

    You are prompted to 'Move mouse to change distance'.

  5. To set the distance from where you wish to calculate the visibility of the point, move the mouse to the required place and left-click to fix it. By dragging the visibility arrow, you can affect distance and direction. You can also type the distance coordinates (two figures are needed) directly into the Command bar if you prefer. This screen shot shows the point in the middle of a street Exit. The arrow has been extended to the required visibility distance.

    You can now set the low and high angles from which your point can be seen.

  6. To set the low angle, move your mouse to the required position and left-click.
  7. To set the opposite (high) angle, move your mouse to the required position and left-click.
  8. You can now review your settings and, if you need to make any adjustments, you can 'grab' the various distance and angle markers by clicking on them and moving them. They are highlighted in red, as in this screen shot.

    When you're happy with the shape of the Analysis Zone, hit Return. The ‘Edit Analysis Zone’ dialog box is displayed.

  9. Enter an appropriate name for the Analysis Zone and click OK.

    The new zone appears in the workspace and in the Object Directory, in the Analysis Layer.

  10. Repeat from step 2 for any more Visibility-based Analysis Zones you would like to place. To exit 'visibility mode', click the icon again.
Parent topic: Visibility-based Analysis Zones