The main problem faced here was setting the region for the line control.

面临的主要问题是这里设置的在线控制的地区。

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Figure 1. The blue line represents the boundary of the clickable region.

图1：蓝色线框是可点击范围的边界。

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Figure 1. The blue line represents the boundary of the clickable region.

图1：蓝色线框是可点击范围的边界。

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