Hi,
If we receive a very big lidar tin and it's very hard to work with, is there a way to copy/duplicate only part of the tin so a smaller one can be created, which is enough to fit purpose, instead of requesting surveyor to send smaller tin?
Regards,
Cindy Wade
Trim Tin
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Lucien West
- Posts: 1131
- Joined: Fri Oct 21, 2005 7:51 am
Re: Trim Tin
If you can get the tin to load ( I like to use a separate 12D project for the large tin).
Can use 'Grid DTM' to produce points within a polygon of the area you want. Also if you are happy to lose tin resolution can specify a bigger grid spacing)
You can then tin these new points.
May also be able to use Grid Tins , but haven't used them much myself.
Can use 'Grid DTM' to produce points within a polygon of the area you want. Also if you are happy to lose tin resolution can specify a bigger grid spacing)
You can then tin these new points.
May also be able to use Grid Tins , but haven't used them much myself.
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Lucien West
- Posts: 1131
- Joined: Fri Oct 21, 2005 7:51 am
Re: Trim Tin
ie have used this method for Wind farm roads. Lidar is for the total area site, but created a rough polygon around all the access roads at an approx 40m wide corridor to allow for road design. At a guess need 20% of the total original tin area....
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Richard Mitchell
- Posts: 238
- Joined: Tue Apr 22, 2014 11:52 am
- Location: Melbourne
Re: Trim Tin
I have this issue too.
Received a new LiDAR DEM and there are over a billion points in it (insert Austin Powers gif here). Most of them are set at RL zero and useless but still take up space. Imported as a grid tin & string fine.
Tried to create a tin from the string and 12d crashed. Tried exploding the points and filtering the data below 10mm. That was 10 hrs of processing with culminating in a crash.
I used to create faces by polygon section to make other LiDAR datasets more manageable and filter delete elements below and RL. 12d has crashed twice this weekend and twice froze the laptop with a black screen, after 8+ hours of processing. Only option is a hard reset in those instances.
My next option is to create many DEM files and hope I get the initial coordinate right for each when splitting. Scale becomes an issue when you get this as a deliverable:
ncols 23731
nrows 43973
xllcorner 321133.2687
yllcorner 6275015.0907
cellsize 0.49997804559438
NODATA_value 0
Received a new LiDAR DEM and there are over a billion points in it (insert Austin Powers gif here). Most of them are set at RL zero and useless but still take up space. Imported as a grid tin & string fine.
Tried to create a tin from the string and 12d crashed. Tried exploding the points and filtering the data below 10mm. That was 10 hrs of processing with culminating in a crash.
I used to create faces by polygon section to make other LiDAR datasets more manageable and filter delete elements below and RL. 12d has crashed twice this weekend and twice froze the laptop with a black screen, after 8+ hours of processing. Only option is a hard reset in those instances.
My next option is to create many DEM files and hope I get the initial coordinate right for each when splitting. Scale becomes an issue when you get this as a deliverable:
ncols 23731
nrows 43973
xllcorner 321133.2687
yllcorner 6275015.0907
cellsize 0.49997804559438
NODATA_value 0
RMitchell
Arup
Arup
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Phil Davies
- Posts: 922
- Joined: Mon Jun 27, 2016 2:14 pm
Re: Trim Tin
What about if you get the las file instead of the tin and import as a point cloud. Then use the option BIM | Point Cloud | Point Cloud Mesh Thinning