In the fast-paced world of AEC (Architecture, Engineering, and Construction), accurate reality capture is transforming how we design, build, and manage projects. XGRIDS SLAM (Simultaneous Localization and Mapping) based scanners are at the forefront of this revolution, offering rapid and precise 3D data acquisition. But how do we leverage this rich data in our everyday BIM (Building Information Modeling) and civil design workflows?

This blog post will guide you through the process of bringing an XGRIDS SLAM-based scan into Autodesk Revit for building modeling and then seamlessly transferring it to Autodesk Civil 3D for site and infrastructure coordination.

 

Understanding XGRIDS SLAM and its Output

 

XGRIDS scanners, like their Lixel series, utilize SLAM technology to create real-time, colored point clouds. What makes them particularly exciting is their integration of 3D Gaussian Splatting (3DGS) via their Lixel CyberColor (LCC) technology, which aims to provide photorealistic 3D representations alongside geometric precision.

While XGRIDS offers plugins for direct integration with Revit (like LCC for Revit, which leverages AI for automated BIM element generation), the core output for interoperability with other Autodesk software will typically be point cloud files in industry-standard formats.

The primary export formats from XGRIDS LixelStudio software for CAD/BIM workflows are generally:

  • Autodesk ReCap Project files (.RCP/.RCS): These are the native point cloud formats for Autodesk software and are highly recommended for seamless integration.
  • LAS (.las) or LAZ (.laz): Open-standard point cloud formats that can be easily imported into Autodesk ReCap for conversion to .RCP.
  • E57 (.e57): Another common, vendor-neutral point cloud format.

For this workflow, we’ll assume your XGRIDS scan data has been processed in LixelStudio and is ready for export, ideally as an .RCP file for the smoothest transition. If you have .las or .e57, you’ll first need to import them into Autodesk ReCap Pro and save them as an .RCP file.

 

Step 1: From XGRIDS to Autodesk Revit (BIM Modeling)

 

Revit thrives on creating intelligent, parametric building models. A point cloud provides the accurate “as-built” context upon which to base your design or renovation.

1. Prepare Your Point Cloud in Autodesk ReCap (if necessary):

If your XGRIDS data is not already in .RCP format, launch Autodesk ReCap Pro:

  • Import: Select “New Project” and import your .las, .laz, or .e57 files.
  • Process: ReCap will process and index the point cloud data, converting it into an .RCP (ReCap Project) file, which references multiple .RCS (ReCap Scan) files.
  • Clean and Crop (Optional but Recommended): In ReCap, you can clean up noise, remove unwanted objects (like people or vehicles that might have been present during the scan), and crop the point cloud to focus only on the relevant building or area. This significantly improves performance in Revit.
  • Save: Save your ReCap project.

2. Link the Point Cloud into Revit:

  • Open your Revit project: Start a new project or open an existing one.
  • Go to the “Insert” Tab: In the Revit ribbon, navigate to the “Insert” tab.
  • Click “Point Cloud”: Select the “Point Cloud” button in the “Link” panel.
  • Select your .RCP file: Browse to the location of your processed .RCP file and select it.
  • Choose Positioning: This is crucial for accurate alignment:
    • Auto – Origin to Origin: If your XGRIDS scan was already tied to a specific project origin or a known coordinate system within its processing, this might be a good starting point.
    • Auto – By Shared Coordinates: This is the most robust method for coordinating multiple models and point clouds. If your Revit project has a defined Shared Coordinate System (e.g., acquired from a civil drawing), and your point cloud was georeferenced to the same system in XGRIDS/ReCap, this will align them perfectly.
    • Manual positioning: For simpler projects or if coordinate systems aren’t established, you can place it manually and then move/rotate it into position.
  • Click “Open”: The point cloud will be linked into your Revit project.

3. Model with the Point Cloud as a Reference:

  • Visibility/Graphics Overrides: In Revit, you can control the visibility of the point cloud. Go to Visibility/Graphics Overrides (VG) > Point Clouds tab. You can adjust the density, color, and even enable “Surface Normals” to help identify surfaces.
  • Section Boxes and View Ranges: Utilize section boxes and adjust view ranges in your plans and sections to slice through the point cloud, making it easier to trace existing elements like walls, columns, and MEP systems.
  • Drawing and Snapping: Use Revit’s drawing tools (walls, floors, roofs, etc.) and snap functionality to accurately model over the point cloud data. The denser and cleaner your point cloud, the easier this process will be.
  • Leverage AI (if using XGRIDS LCC for Revit Plugin): If you have the XGRIDS LCC for Revit plugin, explore its AI-assisted modeling features, which can potentially automate the creation of elements like walls, doors, and windows directly from the LCC spatial model, significantly boosting efficiency.

 

Step 2: From Autodesk Revit to Autodesk Civil 3D (Site and Coordination)

 

Now that you have your detailed building model in Revit, you’ll likely need to integrate it with the site context and infrastructure designed in Civil 3D. While you can bring the point cloud directly into Civil 3D (as shown in the next section), having the Revit model coordinated is often more beneficial.

1. Establish Shared Coordinates in Revit:

This is paramount for accurate coordination. Your Revit model and Civil 3D drawing must share a common coordinate system.

  • Acquire Coordinates from Civil 3D: The most common workflow is to link the Civil 3D drawing (containing your site survey or proposed grading) into Revit and acquire its shared coordinates.
    • In Revit, go to Manage tab > Project Location panel > Coordinates dropdown > Acquire Coordinates.
    • Select the linked Civil 3D DWG file.
    • This will align your Revit project origin and True North with the Civil 3D coordinate system.

2. Export the Revit Model for Civil 3D:

While Civil 3D can attach a Revit model directly, for coordination purposes, exporting to DWG or a similar format is often preferred.

  • Export to DWG:
    • In Revit, go to File > Export > CAD Formats > DWG.
    • In the export settings, ensure “Shared Coordinates” is selected for positioning, and choose the relevant views to export (e.g., 3D view, site plan). This will export the building geometry at its correct georeferenced location.
  • Export to IFC (Optional): For broader interoperability, you could also export the Revit model as an IFC file. Civil 3D can import IFC, retaining BIM data.
  • Publish to Autodesk Docs (Recommended for Surfaces): If you are primarily interested in sharing the Revit site topography or building pad with Civil 3D, consider publishing a linked topography from Revit to Autodesk Docs. Civil 3D can then directly link this published surface.

 

Step 3: Bringing it All into Autodesk Civil 3D (Site and Infrastructure)

 

Civil 3D is designed for large-scale infrastructure and site design. Combining the XGRIDS point cloud and your Revit model allows for comprehensive site coordination.

1. Prepare Your Point Cloud in Autodesk ReCap (if necessary):

Similar to Revit, if your XGRIDS data isn’t .RCP, bring it into ReCap Pro first. This is crucial for optimal performance in Civil 3D.

2. Set Up Your Civil 3D Drawing Coordinate System:

Before attaching any external data, ensure your Civil 3D drawing has the correct coordinate system assigned.

  • Toolspace > Settings Tab: Right-click on your drawing name and select “Edit Drawing Settings.”
  • Units and Zone Tab: Select your desired coordinate system (e.g., State Plane, UTM). This ensures all imported data aligns correctly.

3. Attach the Point Cloud in Civil 3D:

  • Go to the “Insert” Tab: In the Civil 3D ribbon, navigate to the “Insert” tab.
  • Click “Attach” in the “Point Cloud” panel.
  • Select your .RCP file: Browse to and select your processed .RCP file.
  • Choose Insertion Point:
    • Deselect “Specify on-screen”: If your point cloud is already georeferenced and your Civil 3D drawing has the correct coordinate system, the point cloud will insert at its accurate location.
  • Click “OK”: The point cloud will be attached to your Civil 3D drawing.

4. Create a Surface from the Point Cloud (Optional but Common):

One of the most frequent uses of point clouds in Civil 3D is to generate a terrain surface.

  • Select the Point Cloud: Click on the attached point cloud in your drawing.
  • Contextual Ribbon: A contextual ribbon will appear. Look for options to “Create Surface from Point Cloud.”
  • Follow the Wizard: The wizard will guide you through filtering ground points, creating breaklines, and defining the surface properties. This allows you to generate a highly accurate existing ground (EG) surface.

5. Link the Revit Model (or Exported DWG) into Civil 3D:

  • For Exported DWG:
    • Go to Insert tab > Reference panel > Attach (for external references).
    • Browse to your exported Revit DWG and attach it. Ensure the insertion point is 0,0,0 and the units match your Civil 3D drawing. The shared coordinates established earlier will ensure correct alignment.
  • For Direct Revit Link (less common for site coordination, but possible):
    • Civil 3D can directly link .RVT files. However, performance can be an issue with complex models.
    • This is generally better for visual context rather than precise design interaction.
  • For Published Topography (via Autodesk Docs):
    • Go to Insert tab > Link Topography (if using Autodesk Docs and the surface was published from Revit).
    • Select the desired surface from your Autodesk Docs project.

 

Coordination and Beyond:

 

With your XGRIDS SLAM scan, Revit building model, and Civil 3D site design all integrated, you unlock powerful coordination capabilities:

  • Clash Detection: Identify clashes between existing conditions (from the point cloud or derived surface) and proposed designs.
  • Volume Calculations: Accurately calculate cut-and-fill volumes based on existing ground from the scan and proposed grading.
  • Site Layout and Staging: Plan construction logistics with a precise understanding of the existing site and building.
  • Progress Monitoring: Conduct follow-up scans with your XGRIDS device throughout construction and compare them against your BIM and Civil 3D models to monitor progress and identify deviations.

By embracing the power of XGRIDS SLAM scanning and seamlessly integrating it into your Autodesk Revit and Civil 3D workflows, you’re not just creating models; you’re building a digital twin of your project, enabling greater accuracy, efficiency, and ultimately, better project outcomes. The future of AEC is here, and it’s built on a foundation of precise reality capture. Contact us to help find your workflows.