Abstract：To achieve line burning trajectory calculations within a simple polygon, the concept of direction visible is proposed under the condition of line view, eight types of visible lines are found firstly, and seven kinds of bridge structure models are summarized to achieve direction visible division for a simple polygon. Polygonal interior is divided into two point visible areas and two line visible areas under direction projection and the bridges are constructed to complete boundary direction division by using the block relationship between main line and secondary line. Then, combined with point visible division algorithm, the polygon is divided into deep direction visible sub-polygons. Using these sub-polygons, the shortest path from any point to any line is derived within original polygon. Finally, the proposed algorithm is applied to line burning trajectory calculation in a polygon and obtains a good performance.
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2012, Vol. 25 
