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[[deleted]]

Coasts aren't implemented yet. So that's why it's a beach on anteworld.

[cameni]

Not implemented coastlines, that would make the coast shape slightly different. The elevation data should be there, looks it's a slightly different position.

[sailor]

Hello! Finally I got alpha version and tested it a little bit. 
Great job, I just LOVE the concept of Outerra. But I have a question about the accuracy of height map in Outerra. Ok, coasts aren't implemented at all, but what about other places?
Some terrain don’t seem to be very exact and detailed if compare Outerra with Google Earth. For example, I found that often canyons/mountains are not as detailed as in Google Earth. Like Outerra makes mountains and cliffs less steep, and canyons less deep (some pits and ravines are not shown at all).
A small example on Tenerife Island (Spain):
1.
Google:
http://img684.imageshack.us/img684/5921/1g1e.jpg
Outerra:
http://img268.imageshack.us/img268/5912/2o1j.jpg

2.
Google:
http://img14.imageshack.us/img14/5168/3g2l.jpg
Outerra:
http://img534.imageshack.us/img534/6619/4o2cr.jpg

I got a random point (28°20'28.4"N 16°36'27.1"W) on the bottom of small canyon. The height shown in Google Earth is 1462-1463 meters and in Outerra its about 1491 m – 30 meters higher!  It means that the canyon in Outerra was twice less deep as in reality:

3.
Google:
http://img521.imageshack.us/img521/631/5g3e.jpg
Outerra:
http://img72.imageshack.us/img72/6448/6o3r.jpg

The borders in Google Earth seem to be quite steep, about 45 degrees. In Outerra it’s more gently sloping, about 20-30 degrees.
The heights of the edges of that ravine were pretty close to the real – 1504-1512m vs 1515-1516 in Google Earth:

points
Google (edges and central bottom, heights and coordinates shown):
http://img577.imageshack.us/img577/9473/pointsk.jpg

Outerra (the same coordinates):
Left edge:
http://img15.imageshack.us/img15/5953/7o4q.jpg
central (bottom):
http://img706.imageshack.us/img706/4356/8o6p.jpg
right edge:
http://img96.imageshack.us/img96/3896/8o5k.jpg

Only the bottom point is too high in Outerra (1491 vs 1462 in Google Earth).
That is why the ravine doesn’t seem as deep as in reality, and all terrain in Outerra seems to be smoother, less detailed. I noticed it not only on Tenerife, but in other points of Earth too.
 Maybe I did something wrong (I used free version) and I should download more detailed height map? What is the source of your heightmap? I guess it should be huge amount of data. For example if you save the height for each square meter and use 2 bytes for each height (2 bytes will be enough for 1/3 meter precision - 65 536 steps = 21.8 km, enough for describing height  from the Mariana Trench -11km to Mount Everest 8.8km) it will need 4 Gigabyte for only relatively small Tenerife island.. And about 1000  Terabyte for whole Earth! O_O
Perhaps you will make like In addons/mods “ORBX/FTX terrain” for Microsoft Flight Simulator? When somebody needs extremely detailed terrain he just download some gigabytes of accurate height maps for his city/island/state and enjoy playing there?

I think it can be done automatically using Google Earth data (which is quite precise) or some other sources (your own server with 1000 Tb of storage for example .

[cameni]

There are many things that affect it.

• for example, you are comparing image data with elevation data. Image data have much higher resolution, if Google used just the available elevation data to shade the terrain, i would be even worse than in OT.
• there's no self-shadowing of terrain in OT yet, without it the ridges don't look as deep
• we are using global dataset with 90m resolution. There are better sources (30m or even better) but there's no good global 30m source yet (ASTER still needs a few more passes to cancel out the noise). A better dataset can be produced but we didn't attempt to push it for this demo version. Of course the storage and server bandwidth plays its role as well
• lack of land class variety contributes to it as well ...

[RedRiver]

I wouldn't pick on the detail level seeing how the Antarctica is free of ice and the mainland China is glaciated
this is Earth in some remote unspecified future; so close enough is good enough in my book heheh

[mctash]

Is the 30m dataset something you hope to support and include Cameni? (I'm not even sure when those passes will be done so please excuse my ignorance).

[cameni]

Probably not for Anteworld, no need in there, but for a simulator we would like to.

[Jagerbomber]

No need?!      I'm needy...

[cameni]

There are other areas that need attention *before* we can start considering how hilly it looks. Vegetation, biomes, etc.

Also, because of the bilinear filtering that's currently being used when remapping lat/lon aligned data to OT's projection, we are not even fully using the resolution of the 90m dataset.

[sailor]

"for example, you are comparing image data with elevation data. Image data have much higher resolution"
If you move mouse cursor in Google Earth in the bottom of the screen you can see current altitude, it changes every 1 meter (!), really impressive resolution. And it doesn’t change like from one point to another constantly rising or descending during 30m or 90m. It can be like this:
http://img96.imageshack.us/img96/6694/gevaluation.jpg
http://img17.imageshack.us/img17/2700/gevaluation2.jpg
They made very detailed model of a small canyon.
It seems that sometimes resolution of Google Earth elevation data can be about 10m grid– very accurate source.  I think if they used only 90m data (SRTM), the terrains would look very gentle, smooth, without so many details. But you can see – changing of altitude every 5-10 meters or even more frequently!
Google Earth has tool called “Elevation profile”:
http://support.google.com/earth/bin/answer.py?hl=en&answer=181393
Maybe it's possible to write some automatic 'grabber' that can grab Google Earth elevation data? I guess it will not be illegal
" better dataset can be produced but we didn't attempt to push it for this demo version."
Anyways it's great software with huge potential! I hope in future there will be big community making free (or not free) mods and high resolution datasets, available for downloading for some specific regions Please provide the possibility for such enthusiastic modding (something like ‘file -> open -> add elevation data’) 

[flandan]

Hey Cameni, I have been watching this project with great interest for a long time now and when I saw you had an alpha out I had to jump on board immediately. Very impressed so far, and its getting much improved with each update. I was just wondering if you had considered using a much simplified erosion algorithm (like what you find in traditional fractal engines) to take care of the lack of heightmap data. It seems to me that it would perfectly suit the post human world your going for. Also data could be extracted from this process to find the locations of land erosion and rivers to further detail the world.

My experience only comes from using tools like World Machine, but I know its possible. I just have no idea if it could be adapted to work in real-time given your rendering budget.

[cameni]

I've been actually thinking multiple times about using some sort of simplified erosion to enhance the quality of terrain data, whether during the terrain data preparation phase or in run time. There are limitations, but I have a few tests in mind that I want to run to see if it's going to be possible.

[weige]

PHDH Compare

[flandan]

I've been actually thinking multiple times about using some sort of simplified erosion to enhance the quality of terrain data, whether during the terrain data preparation phase or in run time. There are limitations, but I have a few tests in mind that I want to run to see if it's going to be possible.

This sounds really interesting, it would be very good to see a blog post on this if you get any further with it.

[chiefwhosm]

A friend just showed me this and I must say it looks very impressive, downloading the alpha as I type.

The EU download link says Link Invalid (getting it from the usa link).

Perhaps I'm dreaming, but does anteworld allow for adding in new planets etc and if so is it seriously true that it's only going to be $30 to buy?

Or do we have to get the actual engine for such modifications.

Just wondered if there was any network code being built in to either of them