Flickering Polygons in large objects (with example)

[jellix]

Hi,

in the following example: http://www.babylonjs-playground.com/#ZV0MS#0 you can see that the sides of the tube are flickering, although the mesh is thick enough and i shouldn't give a problem.

In line 3 there's a size value of 1000000 (one million). Reduce it to 100.000 and everything's fine.

Of course a cylinder with a radius of 1000000 centimeters(?) is very large. I could scale down my project but I would like to work in "real dimensions", for what I don't want to scale down by factor 10.

Does anybody know a possibility to get the rendering fine in that dimensions?

[RaananW]

Hi jellix,

I was wondering why you use such large numbers. Without thinking much about this I don't have a reason for that not to work with huge numbers, but - http://www.babylonjs-playground.com/#ZV0MS#4 works much better  

[jellix]

Hi RaananW,

thanks for the reply. Well yeah, with a size of 100 it's running better :-) Even with a size of 100.000 it's running well.

There is a simple reason why I want to use a size of a million: The model should become a huge space station with a "real" size diameter of 2.000.000 cm. This is just 2 kilometers which in my opinion is not SOOOO large ...

It's okay when the engine gets in troble with that huge dimensions. By sacling down by a factor of 10 there is no problem anymore. But it just would be nice to be able to work in a real scaled scene because then I could model everything in real-scale, I can zoom into small details and the VR-View gives the correct feeling of the huge size.

I just don't want to scale everything down before asking if anybody knows a solution for the large scenario :-)

[V!nc3r]

You have to set a minZ for the camera

camera.minZ = 10;

but of course this works only if you stand at least at 10 units far from any objects...

As for handle a very large scene, it may be not simple. Of course there will be a lot of work into LODs and divide your scene into chunks, that will be a start

You're not the only one who ask about it, read and test ! https://encrypted.google.com/search?q=game+handle+large+scene

I think you can play to the game Halo for example, to look at how they handle level design when you see all the ring.

Edited August 2, 2016 by V!nc3r

[jellix]

Hi @V!nc3r,

thank you very much - this is the answer I hoped for!

When I am close to an object I can lower the minZ dynamically. The flickering will not appear anymore because the ring is small enought to no get out of my maxZ. Not sure about it, but nevertheless, this is the way to go for now :-)

[Kesshi]

using a logarithmic z-buffer also helps: http://www.babylonjs-playground.com/#ZV0MS#5  (line 38)
https://doc.babylonjs.com/tutorials/Using_logarithmic_depth_buffer

[jellix]

@Kesshi -  very nice - thanks for that!