This post applies if your grid to ground conversion requires applying a horizontal scale about an origin point and is defined by:

- Horizontal Origin Northing (N
_{0}) - Horizontal Origin Easting (E
_{0}) - Horizontal Scale Factor

Scale based grid to ground transformations are probably the most common. If the origin point is not defined, it is usually implied to be 0,0 and so a simple scale can be applied. The wrinkle with this transform occurs when that scale is based on a known point instead of an undefined (0,0) origin. If the user is performing this process step by step, it requires translating the original point cloud data to the known point, applying the scale, and then translating the data back. Luckily, these three steps can be reduced into a single linear transform to obtain the same results by using these formulas:

E' = E * scale + (1 - scale) * E_{o}

N' = N * scale + (1 - scale) * N_{o}

Z' = Z

Now, without the need to make calculations, these can be applied directly using LP360.

## LP360 - Affine Transform LAS PCT

Create the LP360 Affine Transform LAS PCT and/or **LP360 Affine Transform Raster PCT**. Then, input the known values by enabling the Scale and, if applicable, Translate options, plus enabling the Origin.

Then, select the units for your local CRS and the Output folder. We typically recommend "Maintain Source File Structure" and to "GeoTag as Local SRS".

Then, execute the Point Cloud Task on the desired input dataset to generate a new dataset with the scale from the origin point applied.

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