When working with Virtual Surveyor, you may notice a certain tools taking longer than normal. A common cause of this can be the spatiality of your boundary item(s).

The shape and vertices density of a boundary influence can influence Virtual Surveyor's processing performance. The most affected workflows are Cut/Fill maps, Volume Calculation and Export. The simpler a boundary, the better the software will perform.

In this article, we compare the processing performances between simple boundary and complex boundary using the same Virtual Surveyor tools.

## Cut/Fill map

We will analyze the time to produce a Cut/Fill map using two similar boundaries. The boundaries have the same 2D shape. The complex boundary has been densified with a point every 10ft.

Simple boundary | Complex boundary | |
---|---|---|

Boundary area | 28.1 acre | 28.1 acre |

Boundary 3D length | 6004 ft | 8071 ft |

# vertices | 62 | 632 |

Computation time | 3.4 sec | 13.2 sec |

In that case, there is absolutely no value the use a very dense boundary. The boundary is only used to defined the area of interest. The cut/fill results are exactly the same.

## Volume calculation

We perform the same exercise when calculating the volume of a stockpile. The boundaries have the same 2D shape. The complex boundary has been regularly densified at 0.5m.

Simple boundary | Complex boundary | |
---|---|---|

Boundary area | 1192 m2 | 1192 m2 |

Boundary 3D length | 131.5 m | 132.7 m |

# vertices | 30 | 277 |

Computation time | 0.95 sec | 2.14 sec |

For stockpile volumes, you need to assess the boundary density while considering the refence surface accuracy. Remember, the boundary is used to create that surface. If you utilize too simple a boundary, the reference surface can be inaccurate, leading to a miscalculation of the volume results.

## Export

More important than the number of vertices, the shape of a boundary has a significant influence on the performance of image and elevation exports. These two boundaries cover approximately the same area. The Yellow boundary has a larger 2D surface, but a simpler shape.

Simple boundary | Complex boundary | |
---|---|---|

Boundary area | 18371 m2 | 15331 m2 |

Boundary 3D length | 638 m | 661m |

# vertices | 12 | 88 |

Export Image time | 23.3 sec | 41.3 sec |

Export Elevation time | 12.0 sec | 29.1 sec |

To maintain quick exporting performance, try to use the simplest boundary possible. Even if the simple boundary covers a larger 2D area, the export is generally two times quicker.