The PCA was initially designed for Geosun point cloud data. The highlight of PCA is automatic processing, such as filtering, classification, and single-tree segmentation. Users don’t need much operation or interaction with PCA. PCA has two parts, PCA Toolbox and PCA Viewer. PCA Toolbox is only for automatic data processing, and PCA Viewer is mainly for data visualization. Extremely high density, massive data, precise location, penetration of vegetation, fusion of RGB and point cloud,...