- It is my understanding that you want to merge both the overlapping and non-overlapping areas of the two-point clouds. For doing so, you may concatenate the two point clouds using “pccat” function and then downsample using “pcdownsample” function.
- I also understand that you want to increase the density of each cloud before merge. For doing so, you can use the original point clouds, which are dense. You may use rigid transformation in such case. You may refer the following example for reference: