Export each scan to .ptx ascii files

[Christoffer.Brand]

I love to have the ability to export each scan into separate PTX files from ReCap. 

This format is so mutch better than a flat xyz-file format. 

With PTX file you can preserv the transformation information from the laserscanner.

And each point is in its local coordinate system (smaller file size), and the global coordinate relation is in the header (matrix). 

So by multiplying each point whit the global matrix you get the worldspace point.

Its easy to calculate each points normal by compute its closest neighbors (and each point is targeted from the scanner position).

Its easy to compute a image from each point useing grid cells to pick pixelcollors.

And best of all, PTX Ascii format is future proof! If you storage your scans, thay will always have all the requered information to recapture the scaned data, as long as you can read Ascii files (forevere) (as far as we know). 

Here follows a format description of the begining of a ptx-file. 

// I have added some comments after each line

12565 //lattitude grid cells, sphereic relation to the scanners position and rotation angel between cells
4700 //longitude grid cells (Cells are like engine steps for the laserscanner beam to catch each point)
752.639056999993 625.250815000385 42.085689 // x,y,z of scanner position.
-0.157309 0.987549 0 //3X3 matrix (this and the folowing 2 lines)
-0.987549 -0.157309 0 // -||-
0 0 1 // -||-
-0.157309 0.987549 0 0 // complete 4X4 matrix (this and the folowing 3 lines)
-0.987549 -0.157309 0 0 // -||-
0 0 1 0 // -||-
752.639056999993 625.250815000385 42.085689 1 // -||-
-1.300339 -1.056778 -1.678848 0.205203 116 129 101 // here starts messured coordinates 
-1.302322 -1.058395 -1.679733 0.203494 129 143 108 // each line is a point. To get the world coordinate, multiply point with the 4X4 matrix. 
-1.301895 -1.058060 -1.677505 0.215702 118 138 101 // each point is x, y, z, intensity, red, green, blue. The color is a int 0-255

0 0 0 0.5000 0 0 0 // missing points in dataset is made up like this to fill the empty cells in the format. maby laser beam hit the sky, or points removed on in editing software 

... // here follows millions of lines exluded in this example

Here follows the same ptx header whitout comments:

12565
4700
752.639056999993 625.250815000385 42.085689
-0.157309 0.987549 0
-0.987549 -0.157309 0
0 0 1
-0.157309 0.987549 0 0
-0.987549 -0.157309 0 0
0 0 1 0
752.639056999993 625.250815000385 42.085689 1
-1.300339 -1.056778 -1.678848 0.205203 116 129 101
-1.302322 -1.058395 -1.679733 0.203494 129 143 108
-1.301895 -1.058060 -1.677505 0.215702 118 138 101

...

Best Regards

/C

[cody_austin]

Do want to use the PTX for archival purposes or something else? What's the end goal?