Irrlicht Engine

Some shots of the visualisation of Túcume using a DTM derived from aerial photographs and the orthophotos used as texture.

http://n.ethz.ch/~dnovak/download/tucume1.jpg
http://n.ethz.ch/~dnovak/download/tucume2.jpg
http://n.ethz.ch/~dnovak/download/tucume3.jpg

The paper I linked just describes the way to convert from a cartographic projection (X,Y,Z (h)) system into the WGS-84 (long,lat,H) system and back. These formulas are limited to Switzerland because of the oblateness of the wgs-84 ellipsoid (and the gravitational anomalies). For a different country ...

The question is: What kind of reference object do you want to use? Long/Lat coordinates always refer to either a sphere or an ellipsoid. So the first question you have to ask yourself is, which kind of reference sphere/ellipsoid you want to have. There's different formulas depending which reference ...

I was expecting the 1/3 bigger size because of the mip maps - what I didn't know was that the texture is basically 'uncompressed' again, taking the same amount of space like a bitmap. That's why I was surprised by the size. I have another question, that goes roughly into the same direction: When I f...

I suppose the only solution would be to use some form of texture compression like DXT1 or similar to save memory space - just open source (FXT?).

Well if you fill up the GPU ram and still need more textures then textures will have to be switched in and out as necessary which is a costly procedure, so that will kill your performance. Textures are stored in memory uncompressed. So you may have some lovely super compressed JPGs which are tiny o...

I have a dataset which consists of a 3D Model with an aerial photograph attached to it. The texture is made of around 1000 256x256 texture tiles. On my laptop with 512 MiB GPU RAM it runs fine (~500'000 triangles with ~45 FPS). On my working computer (256 MiB GPU RAM) it slows down to 1 FPS. With Ri...

You mihgt want to check the typical 3d scanner models, such as the stanford bunny. Should be available in obj or stl, you can convert the latter into .obj with the Irrlicht Mesh writer interface :) Ah right! You could also just go to the Stanford 3D Scanning Repository: http://graphics.stanford.edu...

glad it helped you. could you possibly give a link to the 500.000 polys mesh ? i'd like to try it with VBOs in with my card too I'd really like to help you out but the thing is that this head was scanned by us with a structured-light system in a museum. Thus I can't distribute it freely as I want (...

I did test VBO's just now. Well - what can I say? That was one hell of a hint

FPS went from 21 to 102 on the 500k mesh (that was on my laptop using a Core2 Duo and a Quadro FX 570M). Incredible! Thanks a lot!

Thank you very much - I will try that out :) kinda offtopic, but if you use VBOs your 23 FPS for a 500.000 polys mesh will become much higher. Do you mean Vertex Buffer Objects? I have no idea how to do them but I'm searching around a bit. Would be awesome to have even higher Frames per Second :)

This is great news :) I am able to load the OBJ models without problem now. But it seems like the OBJ export of Geomagic & Deep Exploration has a bug or the Irrlicht Import imports it differently. (Maybe triangle-sorting?) That's how the 3DS file looks like in Irrlicht: http://n.ethz.ch/~dnovak/...

Thank you very much for the detailed explanation. So I guess I either have to wait for 1.5 or to make groups to export them into OBJ-Files (or just wait for Deep Exploration to convert the files into 3DS-Files ).

I'm trying to see how many polygons the engine can handle on one of our machines. For this I have a reconstructed sand-stone head consisting of 3.8 million triangles. I've converted the file in Deep Exploration into a 3DS file (because Geomagic somehow only allows 65536 vertices for 3DS files). I ca...