The HOOPOS HOOPS Visualize 3DF MVO API supported some cutting plane capability which isn’t available in HPS. Specifically, the use of manipulator handles with cutting planes is different. In 3DF, cutting planes are considered geometry to which manipulator handles could be applied.
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In HPS, cutting planes are not strictly speaking considered geometry. This articles provides code for placement and manipulation of cutting planes in HPS. Additionally, capability that was available in 3DF such as one, two and three sided sections are supported as well as a thin slice.
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