Making a Winter Storm

[ares2101]

My brother-in-law recently took notice of some of my Terragen 2 works and asked me if it would be possible to make a "scenery of a crazy winter storm, lots of snow in a forest with lightning in the back?".

To my knowledge, lightning could be done with a luminous model of such, anyone know of any good ones.  Might it be possible to make falling snow with a suitably manipulated cloud layer?  I've never seen any images on the forums with precipitation or lightning, can this be done?

[bla bla 2]

Si c'est possible, avec un cloud layer, pour faire de la neige qui tombe.

http://forums.planetside.co.uk/index.php?topic=12916.0

http://forums.planetside.co.uk/index.php?topic=10691.0

[ares2101]

Si c'est possible, avec un cloud layer, pour faire de la neige qui tombe.

http://forums.planetside.co.uk/index.php?topic=12916.0

http://forums.planetside.co.uk/index.php?topic=10691.0

OK, I like how the last image in the second link looks, now how do make that for myself?  Also, my French is nowhere near good enough to follow instructions, I had to look up the second half of that sentence above.

[TheBadger]

@bla bla 2: I would like to hear how you made the snow too.

[dandelO]

Here's a test I did about a week ago while trying to work out some snow on a tree I had, it worked but I didn't post anywhere as it was pretty horrible really so, ignore the nasty render. It seems to fit this thread fine, though as an example.

Make a cloud layer, set the height to the same as your camera Y level so you're in the centre of the cloud, make the density fractal suitably small to make tiny clouds. Try scales of 0.1 or even 0.01 all round. Make the colour contrast in the fractal high, you can go higher than '1' if needed. Now open the shader preview window and zoom to the desired view, reduce 'colour offset' untill you can see the amount of specks you like. Sharpen and soften this fractal with the cloud layer controls for density and sharpness. Snow!

[dandelO]

Oh, and just for the sake of it, here's shots of the tree I was playing with, if anyone cares to see it without all that blur ^^.
I had these lying around as we've been trying to sort out Ade's tree models to accept snow layers recently and these were saved as progress previews.

[TheBadger]

@dandelO,

Hey man,

So its like making dust, only you make it white? I guess the trick here is to work in layers so that some spots in the render are thicker than others. Also, detail is really important, to avoid or carefully control noise, to avoid a white noise look.

@ares2101 hi, you can look for a thread titled "blowing dust and mist" (something like that). In that thread there is instructions from T-U that you may be able to convert to snow. Its just an idea, may work for you.

[dandelO]

You could easily just make a uniformly noised fractal with more cover than you need then use a secondary, bigger fractal to apply the density blending to that one. I'd only use one cloud layer.

A low detail for clouds can be good for stills but, if animating, you might, indeed, suffer the 'white noise' effect and a bit more work might be needed.

Here's a couple of videos I made, the first was my first TG2 animation, the second is a rethink of that with much nicer results, I think(although, the falling snow could use some more work in both)...

http://vimeo.com/11672106

http://vimeo.com/24686841

[Dune]

In the case of falling snow it would be good if we could transform (world space transform shader) by function. So every speck of snow, location determined by a PF, could be moved down/sideways by a warped Y stretched fractal. Maybe it is possible.... something to explore one day.

[bla bla 2]

Je vous passe mon fichier, désolé si je parle pas bien anglais,  ares2101.

[dandelO]

Here's another variation I made a time ago in 2008, this time the snow flakes are individual objects in a populator.

[ares2101]

Here's another variation I made a time ago in 2008, this time the snow flakes are individual objects in a populator.

OK, how did you do that?  I'm currently rendering something with a cloud method, but it is taking a very long time.  The idea of a population had occurred to me, but I don't know a way to arrange stuff in three dimensions.

[ares2101]

Je vous passe mon fichier, désolé si je parle pas bien anglais,  ares2101.

Oops, I didn't see the file there the first time around.  Damn translating site screwed up and didn't clue me in. 

Merci

[dandelO]

Hi, Ares. If you take a look on Ashundar, you'll find some files called 'dandelO's Public Library' for download. This is, I think, the only place these files are available now, I removed them from my site and a couple of other places, too, because they were either out of date and some were just plain embarrassing things from my early days of tinkering with TG2!
You might find some decent things buried in there that are still somewhat useful today, though. Eclipses, fire, stones, underwater, caves etc...

I think there's around 20 something projects in total with all 3 volumes. The populated snowflake files are in the 'vol1. update' download, basically, the flakes sit on top of an invisible 'sawtooth-shaped' terrain that isn't connected to the main planet. Might be a good idea to reopen this actually, since ray-traced objects has been introduced to TG. Play around with it.

All 3 volumes are still available here; http://www.terragen.org/index.php?action=tpmod;dl=cat184

*Edit* Just checked and at over five and a half thousand downloads, they must have been of some use to people at some point!

[dandelO]

Actually, the population sits on the default planet, which has 'render surface' unchecked. The visible terrain is a separate plane object. I just had a look again and might play around with it later...

* Check all the settings before rendering, especially in the render node. It appears to be set to only use 2 threads, and lots of new settings have also been added since then, too like microvertex and detail jitter, bloom etc, also, drop 'detail blending' to '0' to speed up rendering x2...