Study on a computing technique suitable for true 3d modeling of complex geologic bodies

True 3D solid modeling of complex geologic bodies still face many difficulties. In this paper, a new technique of true 3D solid modeling is addressed, which incorporates the application of 2D&3D interactive aided section technology to revise scatter point aggregates, the means of two-body 3D data structure (improved B-rep 3D solid data structure) to organize data and the usage of vector shear technology for modeling. Based on such techniques, a true 3D solid model of a large hydropower engineering project in southern China was built to serve as intuitive platform for engineering survey, design, and construction. In the light of its wide application to many projects, it can be considered as a reasonable and effective method for 3D modeling of complex geologic bodies.