基于Delaunay三角网的简单面状要素自动注记

为使地图标注中简单面状要素的自动注记更加美观且高效,提出了一套简单面状要素的注记方案.该方案先用重心法试着将文本标注在重心附近,但当重心法不能将文本标注于多边形内部时,则用改进的Delaunay三角网骨架线法将文本顺着骨架线标注,以适应绝大多数多边形.重心法以O(n)的效率快速标注文本,而改进的三角网建网算法提高了建网效率,保证了骨架线方法的可行性.实验结果表明:该方案注记视觉效果良好,注记效率高.

Automated cartographic text placement of simple area feature based on Delaunay triangulation

In order to make the text placement of simple area feature more reasonable and effective during map labeling, a labeling scheme was proposed in this paper. Firstly, this scheme tried to place text around the center of gravity. While this method could not place text in polygon correctly, the improved labeling algorithm based on Delaunay triangulation would place text along the skeleton stretch of a polygon to fit most of polygons. The center of gravity method can place text with time complexity of O(n), and the improved Delaunay triangnlatioh algorithm had high efficiency to ensure the feasibility of the skeleton method. Experimental results showed that this scheme does not only have well visual effects, but also have better efficiency.