I am using Terrascan to strip vegetation of some ASCII files to create a bare earth model and also to convert the ASCII txt file into a *las (1.2) file.
However, I have noticed that Terrascan (at least visually) seems to grid the imported ASCII data. (The same happens by the way if I convert the ASCII txt file to a *las file before bringing it into Terrascan for processing.)
When I overlay the *las output file with the original ASCII file, the point cloud doesn't "match" up anymore (looks gridded), even though it tells me the number of points remained the same.
It's an xyz + intensity text file.
-10.579645 -1.290032 2131.672373 38 -10.563637 -1.288739 2131.663733 63 -10.549061 -1.287559 2131.653909 117 -10.521391 -1.285341 2131.654799 135 -10.502604 -1.283827 2131.648390 136 -10.498481 -1.283476 2131.629982 139 -10.491604 -1.282907 2131.613836 145 -10.463584 -1.280661 2131.614927 148 -10.528760 -1.285806 2131.540132 137 -10.651209 -1.295494 2131.418934 130
I am exporting out of polyworks as a point cloud (x,y,z,i; and 6 digits after decimal point). No headers, simple text file. When I convert the file to *las (via LAStools), the structure of the file is preserved, but as soon as I import into Terrascan, the file appears 'gridded'. I am not sure if Microstation or Terrascan import settings are screwing with the file. The original txt file is small coordinate numbers (not georeferenced yet).
My problem is that I will have to go to Terrascan eventually for the 'vegetation removal', so I need to find out what's causing the gridding.