Research on the Symbolization Method of Single-Line Rivers Based on the River System Structure

In traditional map, considering only the river itself, we use fine line to thick line from upstream to downstream, but without the relationship of rivers. Paper assign the width of river based on the structural model of the water system, to avoid the conflicting situation, and realize the automatic drawing of river system by using the gradient method of drawing the river. This method can reflect the overall water distribution and overall shape really, to achieve the visual expression of water, and reflects the region´s geographical features, and makes a map better expressed.