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When working with point clouds within Autodesk Infrastructure Design Suite, specifically within AutoCAD Civil 3D, it is important to know what a point cloud is so that we can properly understand how the data will act as we use it with different Autodesk environments.

In its simplest description, a point cloud is a collection of millions or billions of individual x, y, and z coordinates, potentially accompanied by some colorization information. That’s right, nothing more than billions of ‘nodes’ that have no intelligence other than their geometric location, their intensity value, and perhaps a true color derived from photographs taken at the time of scanning.

The communication of this data is typically based on proprietary file formats as structured by different scanner manufacturers. Although every manufacturers ‘generic format’ is different, such as Leica’s .PTS format or Faro’s .FLS format, they typically communicate the same information.

Below is an example of the data formatted within a Leica .PTS file:

Point Clouds within the Autodesk Product Families

In order to accommodate the multiple formats in which point clouds might be submitted to a design firm, Autodesk supplies tools to import, convert, and index point cloud data from almost all scanner manufacturers in the market today. This allows the design firm consuming the data flexibility in the formats they can accept from their scanning providers. Pictured to the right is a list of the file types that can be imported into Autodesk ReCap.

When any of these formats are imported and indexed into Autodesk ReCap, the data is converted into Autodesk’s proprietary formats of .RCP and .RCS files. Each individual raw file imported will create an individual .RCS, ReCap Scan file. As we import multiple files and arrange them with each other, ReCap will save the multi-file configuration as an .RCP, ReCap Project file.

In This Issue

Autodesk ReCap Point Clouds in Civil 3DPoint Cloud Basics

X Coordinate (Easting)

Y Coordinate (Northing)

Z Coordinate (Elevation)

Point Intensity

R (Color)

G(Color)

B(Color)

-30.66595 78.445989 45.923507 -1063 243 248 234-30.664548 78.442084 45.875648 -1018 243 248 234-30.472211 78.413849 45.903482 -948 252 249 217-30.474514 78.419456 45.873745 -963 252 241 200-29.531755 78.313225 45.892969 -1093 255 254 224-30.29249 78.417353 45.916798 -1075 253 252 221-30.100054 78.386315 45.906386 -1007 254 247 209

Point Clouds within the Autodesk Product Families

Autodesk Point Clouds vs. Civil 3D Point Cloud Objects

In This Issue

Autodesk Point Clouds vs. Civil 3D Point Cloud Objects

The .RCP and .RCS products of Autodesk ReCap are sets of point cloud data formatted to be accepted within multiple Autodesk products. These Autodesk formatted point clouds are accepted within basic

AutoCAD (including any AutoCAD-based products such as Civil 3D or Plant 3D), Revit, Infraworks, and more.

These ReCap files can be easily attached and indexed into the AutoCAD environment from the Insert tab of AutoCAD’s ribbon interface, or by typing the ‘POINTCLOUD’ command. Attaching a point cloud with these tools will prompt you to navigate and select your point cloud files. Acceptible formats include ReCaps’ .RCP & .RCS formats, as well as AutoCAD’s .PCG format and Civil 3D’s .ISD point cloud format.

These Autodesk level point clouds can be inserted, viewed, and snaped to using native AutoCAD functionality. AutoCAD gives us the ability to apply visualization decimation of the point cloud to balance the amount of data we see and the performance levels our workstations can handle.

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Additionally, the AutoCAD Properties palette gives us colorization options to change the display of the Point cloud. We can

choose to view the point cloud based on a color mapping upon it’s intesity values, it’s point normals, the point clouds object (layer) color, or the true colors as derived from the photography applied to the point cloud. Viewing the point cloud by intesity values also allows us to chose to map those intensities by greyscale, a full color spectrum, or monochomaticly in red, blue, or green.

Civil 3D, on the other hand, as an object-based modeling system does not recognize an AutoCAD point cloud as an intelligent Civil 3D object. To Civil 3D, an AutoCAD point cloud is a simple entitiy similar to a polyline or a block. The AutoCAD point cloud does not get recognition within the Prospector tab of our toolspace, nor does it have styles applied to it. It can easilly be converted, or recognized, by Civil 3D with a single button pictured above, “Add Civil 3D Properties”. This process prompts Civil 3D to recognize the point cloud as a Civil 3D object, which in turn prompts you to give the Point Cloud a name and a Style. The resulting point cloud then resides within Civil 3D’s Prospector and can be treated as any other Civil 3D Point Cloud.

As in Civil 3D 2011, the ability to ‘create a point cloud’ still exists natively in the software. This process allows you to create an .ISD point cloud database and insert a Civil 3D level pointcloud directly from the raw manufacturer’s generic point cloud format, such as the Leica .PTS or Faro .FLS files.

Once the point cloud is recognized as a Civil 3D object, regardless of insertion method, we’ve got some pretty great Civil 3D based tools available to us.

One of the most exciting tools here is the ‘Add Points to Surface’ tool. Unfortunately, we do not yet have tools of Point Cloud classification; therefore, this tool currently looks to add all the points within the point cloud into the resulting Civil 3D Surface. Unless we’ve done cleanup work in specific point cloud processing software, such as Leica’s Cyclone or Trimble’s Realworks, we will potentially have points on vegetation, street signs, traffic, and all other points in the point cloud included in our surface definition. Currently, this is a huge problem that neither Civil 3D or ReCap can address.

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Unfortunately, this process continues to use the less efficient Autodesk Point Cloud engine that Autodesk employed prior to their acquisition of AllPoint Systems in February of 2013.

The performance differences are significantly noticeable and it is strongly recommended to take the extra step in Autodesk ReCap in order to convert the raw point cloud data into a format that is consumable by our various products within the Autodesk Infrastructure Design Suite as opposed to Civil 3D exclusively.