So many triangles!

No pretty pictures from last night, but I’ve made it into Fiordland which is looking pretty good after correcting areas of dark and ultra bright blue-ish looking photos. The area around Oamaru is a bit of a mess – a lot of blending between different image sets, but not much I can do about that now. I’ve also removed about a thousand clouds.

One thing I’m considering is whether I replace the default mesh with a higher resolution one. This would mean that the landscape would flow a lot realistically with more detail – basically smaller triangles making up the landscape. The challenge is that I’ve not done it before, so it’s a lot of work to maybe come to a dead-end. As far as I can tell I can pay some money for a USB key with a GeoTIFF data elevation file using WGS84  / EPSG:4326 at 8 metre resolution.

I’ll release the South Island with the current resolution before moving on to improving the ortho further and adding a high fidelity mesh.

I’d love to hear if anyone thinks this is worth it, I know the lighting and shadows look much better interacting with more polygons on the landscape. Frame rate will take a high though.



Categories: Flight Simulation

13 replies

  1. If the data is available and produces better results then personally I’m all for it. I understand the issues around FPS taking a hit but over time this is something refinements in XP11 along with advances in PC capability can mitigate to a large extent.

    I dont know whether its possible to offer both mesh options but if I had to only choose one I would 100% say the high quality option. Give me a reason to upgrade my PC! 😉

    Plus given the rugged nature of NZ as a whole, not just the alps in the South Island but the various ranges in the North, this extra resolution will provide an experience that I believe will be outstanding and all the more immersive.

  2. I’ve been using the free ALOS 30m DSM data http://www.eorc.jaxa.jp/ALOS/en/aw3d30/ which has made a DRAMATIC increase in fidelity for my orthos and I was very seriously considering getting the 8m data for NZ as well, but I found that the resolution I got from ALOS with a curve tolerance of 3 in Ortho4XP gave me more than enough detail. I actually did a full comparison between default, original ortho4xp data and custom DEMs. I’ll find the link.

    • Cool – what do you have to do to process their TIF into a usable DEM for Ortho4XP? I figure once I get the ortho sorted out it won’t actually be much effort to batch process new tiles with a different mesh.

      • As long as you are running the python version of Ortho4XP it can process GeoTIFF files (which is what the ALOS ones are). Also if you’re touching up the files in the Orthophotos directory then yes, super easy to go back through and regen your tiles (I did once I found ALOS I regen’d a whole bunch for my Aussie rally).

        The only “issue” is that the ALOS files are DSM – Digital Surface Models which includes the height of things on the “surface” where as DEM – Digital Elevation Models are the height of the surface ground.

        To “get around this” the ALOS files have two versions, AVERAGE and MEDIAN. I’ve used the MEDIAN files for all of mine as I figure they are going to be “closest” to ground level.

        I’m going to be flying from Agra – Kathmandu – Lukla – Paro shortly so I’m doing (P3D) terrain for that area and the difference is DRAMATIC versus defalt mesh.

      • Cool – thanks. I guess I’ll need to learn the script commands for python. How did you tell ortho4xp to look at all the tiff tiles? Or did you processn them into a bigger tiff first?

      • No need to learn Python (I don’t) and there’s a great tutorial on setting it up completely. I’ll find it and link it here.
        Each tiff is for one latlong sector just as Ortho4XP needs so when processing a tile you point it to the tif for that tile in the custom dem section.

        Try the New Plymouth area as your test since I found that had a dramatic difference I could see immediately even as I took off from the airport and flew to the mountain.

      • Excellent – that’s what I need. I think I might exclude Auckland and Wellington if tall buildings are an issue. Fun times.

      • Other thing you can do is revist this when you get high mesh files for the different areas, like getting the lidar data for wellington and using that for that one area.

  3. OK here is the link to my gallery that compares default, ALPilotX, and Ortho4XP Custom DEM:

    • Wow, that comparison shot between base xp, AIpilot and Ortho4XP Custom DEM is amazing. The Ortho4XP Custom DEM version is incredible!

      • Yep, and there’s not really THAT much advantage for going any lower than a curve tolerance of 3 with the Custom DEMs as you’re not going to see that detail unless you are 100′ off the deck. In which was you would increase the detail for that one area when generating it as opposed to the other areas.

        To get close to the same level of detail with Ortho4XP’s default mesh source you need to go to 0.5-1 on curve tolerance, where as with the custom DEMs you’re starting around 3 and so have MUCH more scope to get even more detail.

        Highly recommended!

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