CGSRobotics - Visibility demo

: Last Updated: Tuesday, 24 January 2012 16:25; Published: Friday, 20 January 2012 12:48

Visibility Polygon Demonstration

The visibility poligon for the point is computed by a geometrical algorithm proposed by Suri and O'Rourke This algorithm performs an angular sweep among the vertices of the polygons, avoiding the use of raycasting techniques. Its computational cost is O(n log H). Further information can be found here.


Usage draw a main polygon on the gray area at left. draw one or more polygons inside the main polygon select a point from which the visibility polygon should be computed. Note: the selected should be a point inside the main polygon and outside the internal polygons To draw the main polygon click the left mouse button on a point inside the gray area move the mouse to draw a segment click the left mouse button to confirm the current segment add any more segments in the same way close the current polygon by clicking the right mouse button	To add internal polygons click on the "Add Internal Polygon" button and do as said above. when the desired geometry has been completed click the left mouse button when the mouse pointer is on the desired point. Other Buttons "Remove Last Line": deletes the last segment of the polygon that is currently being drawn "Remove Last Polygon": deletes the last inserted polygon "Reset": clear the gray area to allow drawing a different geometry