Using Point Cloud Files in a Project

Video: Using Point Cloud Data in Revit

In projects involving existing buildings, the need to capture the existing condition of a building is often a critical project task. Laser scanners can be used to sample points from the surface of an existing physical object, such as a building, and save this data as a point cloud. The amount of data produced by this specialized laser scanner is typically huge (hundreds of millions to billions of points), so a Revit model links a point cloud as a reference rather than embedding the file. For efficiency and improved performance, Revit uses only a limited subset of points for display and selection at any given time. Multiple point clouds can be linked and multiple instances of each link can be created.

A point cloud:

• generally behaves like a model object within Revit.
• displays in various modeling views, such as 3D, plans, and sections.
• can be selected, moved, rotated, copied, deleted, mirrored, and so on.
• is cut by plans, sections, and section boxes, allowing you to easily isolate sections of the cloud.

Controlling visibility: Control the visibility of the point cloud on the Imported Categories tab of the Visibility/Graphics Overrides dialog, as well as on a per-element basis. You can switch the visibility of the point cloud on or off, but you cannot change graphical settings, such as Lines, Patterns, or Halftone.

Creating geometry: A snapping feature simplifies model creation based on point cloud data. Geometry creation or modification tools in Revit (such as wall, line, grid, rotate, move, etc.) can snap to implicit planar surfaces that are dynamically detected in the point cloud. Revit only detects planes that are perpendicular to the current workplane (in plan, section, or 3D) and only in a small vicinity of the cursor. However, after the workplane is detected, it is used as a global reference until the view is zoomed in or out.

Managing linked point clouds: The Manage Links dialog includes a Point Clouds tab that lists the status of all point cloud links (types) and provides standard Reload/Unload/Remove functionality similar to other kinds of links.

Using point clouds in a worksharing environment: To improve performance and reduce network traffic, the recommended workflow for users who need to work with the same point cloud files is to copy the files locally. As long as the relative path to the local copies of the point cloud files is the same for each user, the link will remain valid when you synchronize with Central. The relative path is displayed as the Saved Path in the Manage Links dialog and is relative to the Point Cloud Root Path specified on the File Locations tab of the Options dialog.