Could lastool convert .txt to .obj?

[Yitong Jiang]

Hello,

Could .txt file be converted to .obj using lastool?

Thank you!

Yitong

[Martin Isenburg]

Hello,

The las2tin tool can produce TINs in the venerable OBJ mesh format. Try

las2tin -i slow.txt -o slower.obj

Martin @rapidlasso

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[Yitong Jiang]

Hi Martin,

Is there a way to convert point cloud file to .obj without making it TIN?

Thank you!

Yitong

On Wed, Feb 18, 2015 at 11:58 AM, Yitong Jiang <yito...@gmail.com> wrote:

Hi Martin,

I did las2tin, however, when I try to view the obj file, there is a lot of warnings. Please see the attachment. Do you know what might be the possible cause?

Yitong

[Yitong Jiang]

Hi Martin,

I did las2tin, however, when I try to view the obj file, there is a lot of warnings. Please see the attachment. Do you know what might be the possible cause?

Yitong

On Tue, Feb 17, 2015 at 10:37 AM, Martin Isenburg <martin....@gmail.com> wrote:

[Martin Isenburg]

Hello,

It worked correctly (so it seems to me) but you cannot load and view the resulting mesh in OBJ format with lasview ... the lasview tool can only display points (and do some neat tricks on them).

Martin

Martin

[Martin Isenburg]

Hello Yitong,

it is my understanding that the OBJ format [1] is mainly used for meshes and TINs that are optionally textured or have normals. Ten years back we wrote a paper why such indexed formats are not well suited for storing the massive meshes we see today and suggested the use of "streaming formats" [2] instead.

However, you can generate an OBJ file containing only vertices as follows:

D:\LAStools\bin>las2txt -i ..\data\fusa.laz -parse Exyz -extra v -o fusa.obj

D:\LAStools\bin>more fusa.obj

v 277999.97 6122342.20 64.35

v 277999.97 6122342.53 64.30

v 277999.52 6122339.74 63.09

v 277999.55 6122340.05 62.88

v 277999.53 6122340.41 63.00

v 277999.53 6122340.75 63.04

v 277999.55 6122341.07 62.86

v 277999.48 6122341.81 63.46

[...]

or - to avoid creating a file on disk - like this

D:\LAStools\bin>las2txt -i ..\data\fusa.laz -parse Exyz -extra v -stdout | more

v 277999.97 6122342.20 64.35

v 277999.97 6122342.53 64.30

v 277999.52 6122339.74 63.09

v 277999.55 6122340.05 62.88

v 277999.53 6122340.41 63.00

v 277999.53 6122340.75 63.04

v 277999.55 6122341.07 62.86

v 277999.48 6122341.81 63.46

v 277999.85 6122342.39 60.07

v 277999.64 6122343.30 61.93

[...]

Regards,

Martin @rapidlasso

[1] http://en.wikipedia.org/wiki/Wavefront_.obj_file
[2] http://www.cs.unc.edu/~isenburg/sm/