@solo said:
Got a dropbox account? they are free, safe and private.
No but I can get one. Where do you reccommend?
@solo said:
Got a dropbox account? they are free, safe and private.
No but I can get one. Where do you reccommend?
@solo said:
If you can upload it, or part of it, I'd like to try something with Terragen.
I tried uploading it earlier and it was rejected because the file was too large.
@solo said:
Got that in a DEM file? or even .obj, dxf.
Yes. I am actually using a DEM file as the source for the sample DXF I uploaded.
@mac1 said:
Other filtering approaches using MeshLab again but this time doing Vertex Clustering Decimation. SU edges 25625,16900 faces and file size 2599K. The filters it includes are some developers have incorporated in their apps. .Vertex Clustering Decimation.jpg[/attachment]
IMO trying to take this model and editing is not the way to go based on the goal of your OP. To create a virtual tour you must get to the point of selective editing only portions of the map along the lines bjornkn discusses This can be in the decimation or interpolation sense
Next step, layers and selective edits?
Those results look quite promising and seem to retain much of the fine detail.
I completely agree about only editing certain portions along the line. Given the sample I uploaded, a true sense of perspective is lost. Here is a set of 3 meter contours for the entire area involved. I would upload the full resolution version but the file size exceeds the attachment limits. The small patch I uploaded is located near the lower portion of the midpoint. See attachment:
@solo said:
No, remove 90 percent. see file size from 35MB to 2.6MB
see image:
Then there is hope for it still. I am doing the same, or so I thought, but the results are not like yours. I wonder what it could be? My version comes out with strange patches or blotches all over it..
@solo said:
Sure.
Open dxf in SU, then save as SU6 version.
Open it up in DE, and select reduce, process and select 90 percent. Then select heal and save as SU model.That's all.
Oh, I see. So you were only removing 10% of the triangles. No wonder I was having issues, I was clicking 10%, thus removing 90% of the triangles.
@solo said:
The earlier one was Deep exploration, the above was Vue, I simply imported the dxf and painted terrain by elevation. No need to reduce as Vue can handle billions of poly's without glitch. However I can reduce in Vue and export to SU if needed.
I have Deep Exploration and have tried to replicate the reduction results you achieved earlier but without success. Can you tell me how you did it?
@solo said:
Vue9 can import the dxf, dem, ect, then assign material based on slope, height, orientations or even selected with paint brush tool.
Here is a very fast example.
I'm a bit confused... So you used Vue to do the reduction shown earlier? I thought you had used Deep Exploration but when I tried a 90% reduction, it it didn't look very good.
@bjornkn said:
Do you really have any choice? Even though DE may do a good job reducing the mes it will not add any detail where there is none. Neither will it use different rules in selected areas (my version doesn't anyway).
Have you actually tried the GP/Triangulate method? It is actually quite fast, and allows you to add detail exactly where you need it, and it allows you to add some edges/creases where there are only ssoft dunes in the dxf mesh.
Like on this little 100 faces patch elevated 50cm to make it visible entirely above the ground. 5mins?
What is GP?
@bjornkn said:
Thanks for the coordinates.
After having a look I'm even more confused why you insist on having all the details in the mountains, with ridge lines etc, when they are not visible at all because of all the trees?
The perceived landscape is even much smoother in the hilly areas than on my simplified versions. Not only will a more detailed version contain way too many faces, but it will also look wrong because you should really "model" the forests instead of the ground below, as it isn't visible anyway.
And at the same time you have the ground level with Lidar clutter, too little details and too smoothed. I think you'd be much better off with making this by hand. That way you may even end up with a full model that is managable in SU
While the primary purpose of the terrain will be to display various scenes from the area, it will also be used to show mining and other activity which requires that some level of detail remain in tact. The mountains do not have to have much detail, other than the general shape, but the lower elevations absolutely must have crisp boundaries because of the proximity of homes, roads, streams, and railroad lines, all tightly packed in among the mountains. You would have to see the area up close to understand fully because satellite images just don't do it justice.
Drawing an area of this size by hand is not a task that I would want to even contemplate doing. Especially with the terrain involved.
This is slightly off topic but I just had to say that I had a look at your website... NICE WORK!
@solo said:
Hey guys, I have not read this whole thread, I just jumped in here, I'm guessing it's about using large terrains, if not please ignore everything from here.
The first example (hand sketch) you posted reminds me of an idea that I had originally considered, where I thought about "tracing" over the grouped contour lines to capture all the major details (shape) of the mountains. After some brief experimentation, I quickly discovered that it would have taken forever to do because I wish to maintain as much detail as possible in the lower elevations and especially in the stream beds. It is still an interesting notion, however.
@bjornkn said:
@dbwv69 said:
That's probably a good idea because debating "free" v/s "paid" isn't doing a thing to help me achieve my goal. BTW: Did I detect a note of sarcasm there?
I'm afraid I couldn't hide it completely
Nevertheless I couldn't resist wasting another hour+ on this terrain after you posted that "little" dxf detail.
All free tools (I think there are free guide point tools? Although I did use the one in Amorph)
I will not post the Amorph version... It didn't have a chance trying to polyreduce that beast of a terrain in any reasonable amount of time, but could easily build a terrain on top of the dxf.
[attachment=0:2qr61cuc]<!-- ia0 -->dxfterrs.jpg<!-- ia0 -->[/attachment:2qr61cuc]
I obtained similar results using the method mentioned earlier. The face counts are still high but it is definitely a step in the right direction. I'm thinking I can get a reduction of around 90% and still maintain just enough detail in the valleys to make it useable.
It may take some tweaking to get it just right but I am more convinced than ever that it can be achieved.
@mac1 said:
Thanks for the file, I have SU7 free with the dxf import add on so was able to open file, used TIGS obj exporter to create obj file for MeshLab. In my dabbling https://sites.google.com/site/sagesuwiki/tutorials/tips#TOC-MeshLab:-Centric-View-of-Polygon-Me I have convinced my self the export by kmz is better than dae alone and that I seem to run into problems with dae and MeshLab declaring self intersecting faces. I have also noted the axis issue and scaling but previous apps I did not worry too much because of the relative small components I was dealing with.
For your case in MeshLab ( obj file) there was 479K+ duplicate vertices deleted. ( I don't merge vertices because the model can get distorted. For terrain probably Ok but not component model. Zero self intersecting faces, zero non manifold vertices and edges I could see (ML paints them red so for large mesh they get hard to see). Did quad collapse decimation and at Ml recommended value collapsed down to 49k+ vertices and 98k+ faces. Will dabble some more but for what it is worth here is the dxf file exported from MeshLab file[attachment=0:24kp526k]<!-- ia0 -->Baseline ML.zip<!-- ia0 -->[/attachment:24kp526k]
Very good work! The results you achieved are exactly what I am looking for. How did you do it?
@solo said:
Hey guys, I have not read this whole thread, I just jumped in here, I'm guessing it's about using large terrains, if not please ignore everything from here.
I say do not do it, SU buckles at it's knees, use a third party app like Terragen or Geo control, even the new Vue can do it great these days.
If you do need to the use a good reducing app like deep exploration (very expensive).
Here is your sample, brought directly into SU was 35MB, reduced to 2.6MB, can go lower but this was a good balance as nothing much in detail was lost, I reduced it by 90%.
[attachment=1:20afzex3]<!-- ia1 -->sample section reduced by 90 percent.jpg<!-- ia1 -->[/attachment:20afzex3]
Softened:
@charly2008 said:
Hello Geo specialists,
I am a beginner in terms of geographic information systems. But I am very interested in this subject.
I have a question and would be delighted to receive a response from you. Is it possible to produce a TIN from SRTM 90m Digital Elevation Data and how is it done?. I own Global Mapper 11. Thanks in Advance.Charly
For the best results, using Global Mapper, you can export the data to either a DXF Mesh file or a DXF 3D Face file but you will need Sketchup Professional to import it.
Alternatively, using Global Mapper, you can export the elevation data to a DEM (Digital Elevation Model) and import that into the free version of Sketchup but the results (in my opinion) aren't as good.
Another method is, using Global Mapper, export the elevation data to an XYZ file and import that into Sketchup as a point cloud with the Cloud plugin. You will then have to triangulate it with either the Cloud plugin or another plugin designed for that purpose.
Lastly, using Global Mapper, you can generate contour lines and export them as Vector data to a DXF file and import that into Sketchup then convert the contours to a mesh using the Sandbox tools but again, you will need Sketchup Professional to import the DXF file.
Whichever method you choose, it is still possible to have problems with the amount of data involved, depending on the size of the area you are using. If you have problems, try changing the sample spacing to a higher number in Global Mapper, prior to export. It will reduce the amount of data but the resolution will suffer as a result.
@mac1 said:
dbwv69
I have had some what similar problem with Su=>Collada=>MeshLab=< Su( Collada) and then see a number of self intersecting faces and the obj works much better. Belnder has bug reports, ref. Collada import, my check of latest stable release shows the patch is not yet included but fix is known.
Ploy reduction is one of the easier filters in MeshLab to apply ,but as I am sure you know there are many more. I was thinking the Poisson smoothing could help your problem. I dabble with MeshLab so if you can post even a section I'll take a look. May not get any where but will at least try.
G day and good luck
Thanks for the help, I appreciate it.
I was reading about the Poisson smoothing and while I have not yet experimented with it, the reports I read do sound promising. So far, using MeshLab I have been able to achieve decent results by applying a Quadric Edge Collapse Decimation filter, which produced a TIN that closely resembled the original symmetrical mesh, only at a greatly reduced polygon count.
However, I did notice one thing that could potentially cause problems with proper alignment of the completed terrain meshes. The mesh somehow gets rotated on it's axis when it's imported back into Sketchup. I don't know if it's caused by MeshLab or some part of the convoluted import/export process needed between the various programs.
I extracted a small sample of the area I am working with from the original 3 meter Lidar data, and exported that to a DXF 3D mesh file at full resolution. I can convert it to other formats if needed. See attachment: Sample Section DXF.zip
@bjornkn said:
But then you already have the solution then? Your 25 sq miles should be around 5-6 million triangles at 3x3m resolution, which should convert to around 150k faces in SU, which might work. Then you just have to figure out how to texture it with a 70+ Mpx orthophoto to get 1x1m resolution (which isn't much btw)...
Texturing with the orthophoto no longer a concern to me because I have already solved that problem and it's resolution isn't critical because it will only be used as a background texture on the mountains.
@unknownuser said:
OK. As you don't seem to be interested in advice along that road (if it costs anything at all) I think I'll stop spending my time on this "journey" of yours.
Looking forward to see the results though.
That's probably a good idea because debating "free" v/s "paid" isn't doing a thing to help me achieve my goal. BTW: Did I detect a note of sarcasm there?
I had no idea if you were the one who made the plugin or not but after your having mentioned it several times, even after I made it clear that I wanted to seek free alternatives, it certainly began to look like you either had an agenda or were affiliated in some way.
As for using hammers and screwdrivers...
My problem is somewhat unique and as a direct result, it requires creative and innovative solutions. Fortunately, there are no deadlines so I can spend as much time as I like while trying to find an adequate solution.
How do you think that all these nifty plugins and addons for Sketchup were created in the first place? Quite simply, because someone took the time to do the hard work while trying to find a solution to a problem, whatever that problem might have been. Besides, some of us simply like the challenge.
Speaking of test results, using Meshlab and a variety of other tools, as mentioned earlier I was able to take a terrain mesh containing over 400,000 faces and reduce it down to a mere 10,000 faces while still being able to maintain an appearance that was very close to what I am seeking. All without the need to purchase anything. Plugins are great but they can't "fix" everything.
We aren't talking about a small flat patch of land around a house or even a small sub-division here. I am planning to model an area of over 25 square miles in mountainous terrain and knew very well that it would not be easy before I even began the project. Sure, I could have simply used CAD or one of the other miriad of paid-products made specifically for a project such as mine, but what fun would that have been?
Sometimes it isn't about the destination but about the journey itself.
@bjornkn said:
I have no idea what makes you think that I will get any bucks by advicing you to buy a plugin?
I make no plugins or programs currently, and I will not receive any royalties or any other "bucks" by pointing at any non-free plugins.I don't use Meshlab (free?) or Global Mapper ($350+?), but have bought Amorph and Artisan, and am very happy that I did because it saves me tons of time and makes it possible to do things in SU that would be impossible without them. BTW I have also bought that Mootools/Polygon Cruncher as well as Okinos NuGraf/Polytrans (which will also poly-reduce) and many other tools.
When I need to screw a screw into a wall I prefer to buy a (cheap) screwdriver instead of trying to use a hammer, or to spend hours/days looking for a free screwdriver or make one myself.
BTW, I just did a little test on that handmade terrain I posted earlier. By downsampling selected areas with Amorph (10secs) it looks identical at a distance, and is now 4000 faces, and with the ortho photo intact. Even at <2000 faces it looks pretty good. As you're not interested in solutions that costs a few bucks I won't bother to post the results though.But, by all means, it would be great if you could write a free polygon reducer plugin that makes it possible to do local/area(/altitude?) reductions, and will allow you to stitch the parts together easily afterwards. I'm sure you could even charge a few bucks for such a plugin - and I would probably buy it too
@mac1 said:
Can you post your model. It will probably not fit the 3d ware house limit and probably not the Google docs but possibly one of the free ftp sites or post a section. Thinking you may not have not spent enough time with MeshLab? Check drop box it gives a large file size upload
Unfortunately, I don't really have a model yet, at least not one of the full area involved. Originally, I tried creating one and it killed Sketchup so I was forced to seek out alternatives that could simplify the poly counts of the terrain mesh while maintaining an acceptable level of detail. Ultimately, I decided to split the terrain mesh into several segments but again, each of them alone is more than Sketchup can handle without significant poly reduction.
I have managed to make some progress using Mesh lab, after considerable efforts were made to determine why the program kept crashing. As it turns out, it was the file format (Collada) that I had been using to get the data into Mesh Lab. I switched to using OBJ files and the program appears to be much more stable now.
For example, using Mesh Lab I was able to take a terrain mesh containing 400,000 faces and reduce it down to a mere 10,000 faces while mataining a relatively nice appearance. Granted, that was an overall poly reduction, which doesen't exactly achieve my goal of maintaining high levels of detail in the valleys and low levels of detail in the mountains, but it is closer than any previous methods I have tried.
By dividing the mesh, using poly reduction, and careful trimming of unnecessary areas, I am now convinced that I will eventually be able to create a nice terrain mesh for use with the model(s) I am planning. It is only a matter of time now.
@bjornkn said:
It's not so much lack of horsepower as getting used to driving with a manual shift
But if you want to drive at top gear everywhere you'll not gonna make it work for you.
If you absolutely need to have a 3x3m res in all of your terrain then SU is not the program for the job. 5-6 million polys can probably easily be handled with Blender, and so can most other non-free 3D programs, like LightWave, which is what I'm using when I need thousands of instanced 3D trees, rocks, grass and lots of polys.
In SU you have to "adapt to the terrain" and keep your polycount as low as possible wherever there's no need for lots of detail.
The SU community is so spoilt by all the great free plugins available, as well as lots of affordable ones. Sometimes you can't do without them, but sometimes you can spend a few days/weeks working hard instead of spending $39/$149.
In my case, it was a matter of getting used to driving an automatic. I could achieve this with any number of other 3D programs, including AutoCAD, but none of them offer the simplicity or ease of use that Sketchup offers. For a model of this nature, the precision such as that offered by AutoCAD simply isn't necessary and would be akin to using a construction crew to build a park bench.
As stated previously, I do not need high resolution in the entire model and am trying to achchieve some level of compromise between high resolution in the valleys and low resolution in the mountains.
What I am trying to do is possible and one way or another, I will achieve my goal, even if it means learning Ruby and writing my own plugin. I am a programmer ya know, just not in Ruby.
@bjornkn said:
As advertised on this page currently there is {SNIP}
I can appreciate that you want to make a few bucks but I've already made it very clear that I am not interested in buying a plugin at this time. Using pretense to lead into a sales pitch isn't going to change my mind. Besides, I am not fully convinced that your plugin will do exactly what I need to do.
Finding free solutions may not be easy, especially when they are buried under a mountain of advertisements or misleading "free" solutions that aren't really free but don't tell you that until you download and try them, but truly free solutions are out there and I fully intend to find them.