Clouds

How do I make semi-realistic clouds?
I am currently confuzzled
:expressionless:

You could make clouds with particles.

  1. Make a box.
  2. Subdivide it a lot.
  3. Use proportional editing to make it more cloud-like. (Select/Random is very useful in this phase.)
  4. Make a halo texture for the cloud. (Shaded on gives you darker clouds)
  5. Tweak the cloud and the texture till you get the result you want.

This could be also done by making planes and assigning a cloud procedural texture to them. Remember to set color to procedural and set alpha of the texture on in the material settings.

Planes Are MUCH slower than particles and blender seems only to support transperency up to a 30 transparent planes or soā€¦

you canā€™t. simple as. trust me Iā€™ve been trying for 3 years.

Hi pencil productions,

Take a look at this thread :-

https://blenderartists.org/forum/viewtopic.php?t=42633&highlight=clouds+cog

I shall be releasing a Cogā€™s Quick Tutorial on cloud creation this month but do look at some of my concept work on my website:-

www.cogfilms.com

It really depends on what you want to create however. Nothing is impossible but some techniques are not easy in Blender (at the moment).

Cog

okā€¦Iā€™ll bite. Realistic clouds are currently impossible. Semi realistic clouds are currently impossible. Passable clouds are just about doable, but it really is a scrapeā€¦

this was my main motivation when creating all those skymaps. I was tired of the turd output that blender was generating (cloud wise) and I was tired of using the same static backgrounds that donā€™t change when you rotate your camera around the model.

Hi again M@dcow,

I wonā€™t bite. Clouds are impossible to bite they leave a damp smokey taste in the mouth.

Cog

Yeahh,ā€¦ thanks for posting, I tried putting layers of planes in the sky and then applying clouds textures to them. The only thing is how do i get it to shine through where it is dark, so it actually looks like clouds

Have you set the alpha of the texture on? (found in Shading/Map To/Alpha) Remember to set Colorband of the cloud procedural texture so that the alpha of the left end is 0 and the right end is white and itā€™s alpha is more than 0.

ZTransp in F5, Mirror Transp tab.

%<

Is it possible that future versions will tweak the new fluid simulator to provide ā€œgasā€ features? It was the first thing I tried to accomplish when I downloaded the new beta. Didnā€™t get any good results but it seems like a big piece is now there.

Is it possible that future versions will tweak the new fluid simulator to provide ā€œgasā€ features? It was the first thing I tried to accomplish when I downloaded the new beta. Didnā€™t get any good results but it seems like a big piece is now there.[/quote]

I sure hope so, Iā€™m hurting for this too, and if somebody could make it work. WOW.

hello everybody, this is the first cloud I made that is not a plain, it looks almost perfect :stuck_out_tongue: in certain circumstances (distance from camera is big factor) but it can look grainy when you get far away :-? . Oh well any constructive criticism would be outstandingā€¦

Please go to [>] pencilproductions.blog.com to see cloud picture

thank you [!]

One way I found is to use multiple planes or curved surfaces (a simple NURBS surface will suffice). Now, when I say multiple, I mean MULTIPLE, like 30 or 40. Here is how.

Create a plane and delete two vertices. Now, take the other two and rotate them to where they are placed one on top of the other. The distance between the two will decide the thickness of your clouds. Subdivide your new line till you have between 30-50 vertice (look at the top of your window for a vertex count of the currently selected object in edit mode). Move it to where you want your cloud layer to be and leave it.

Now, either create a plane or simple NURBS surface. Size it to whatever size neccessary (I found that the surfaces work well with terrains). Move the plane/surface to your line. Make the line the parent of your plane/surface. Then, select the line and use dupliverts. What you see before you should be your plane/surface multiplied and sitting one on top of the other, with fairly little distance in between them. If the layer is too thick, or the planes/surfaces are too far apart, select your line and scale it in EDIT MODE. If you do it outside of edit mode, you will scale your clouds as well.

Now comes the tricky part. Select your cloud plane/surface and give it a material. To set it up properly for shading, turn alpha all the way to 0, give it a white color, turn translucency to 1, and turn spec down to 0 as well. For preview purposes, turn all buttons related to shadowing off (trashad, shadow, and traceable). For your final render, youā€™ll want them to be on. And here is the key to making it work: Instead of using raytrans, use Z-trans for your transparency setting. It allows you to use as many surfaces for trans, with certain limitations which I will explain later on.

Now, add your cloud texture (blenderā€™s works fine), and use the color ramp of the texture to add space between your clouds, typical settings is a marker at 0.5 with white color and alpha 0 and another white marker at 1 with alpha 1. Noise depth and size are set to personal taste.

Now, under the ā€œMap Inputā€ tab, turn ā€œglobā€. BE CAREFUL! ā€œGlobā€ makes the procedural texture smaller than ā€œOrcoā€, so you might need to map it less than 1 in each dirction or turn the noise size up or both. If you render with all shadow buttons off, then you will get alot of white, but it will give you a general idea of where your clouds are. With all options on, you should get some pretty decent clouds.

http://img228.imageshack.us/img228/8053/cloudtest0kl.jpg

This was just a test render. This image was rendered with a NURBS surface, scaled to be wider and longer, but shorter at the same time, multipied along said line with 33 vertices, so there are 33 NURBS surfaces. The cloud texture is set with the color ramp settings I mentioned earlier. Noise Size is 2 and Noise Depth is 6. ā€œMap Inputā€ settings are ā€œglobā€, with an X and Y size of 0.25 and the Z size set to 0.5 (to make them look flatter).

Here are a couple of notes to remember:
These clouds will not work properly with reflections. Even though the faces are Z-trans, raytraced reflections still treat them like raytraced surfaces, so you end up with only 9 layers rendering transparent and all the rest would be solid white.

Shadows (Like reflections) wonā€™t work right either. You can get shadows from the clouds and onto the clouds, but through the clouds wonā€™t work because the shadows are raytraced.

You arenā€™t limited to only the cloud texture. Any texture (even images) will work with this trick.

If you used a sphere instead of a plane, take a line, subdivide, delete the edges in between the vertices (extrude, select one half, delete edges, select other half, delete vertices), spin it in two directions to make a sphere and voila, you have planetary clouds.

You donā€™t have to place the clouds above the camera, this trick works great for fog as well.

If you place the camera inside the clouds, it would look veryā€¦ummā€¦not cloud like. Try using planes facing the camera instead.

Most importantly, this trick has a tendency to jack up render times and eat alot of ram, so be careful!

I hope thi was helpful (although it was lengthy).

Sorry about the picture at pencilproductins.blog.com, I couldnt get it to load, maybe later.

iokua83; thank you for posting this, its exactly what I needed, thanks. I think that if i combine this and the cloud that I made earlier today, I can get really nice ā€œflying through the cloudā€ effects wich in one scene of my movie is very important!

Again thanks :smiley:

what I would like to know is: Is there someone working on clouds or something like that?

becuae I donā€™t think it should be too difficult. There is just one feature that would be enough to make realistic clouds. Particles do also ahve to cast shadows. But not the noirmal shadows, becuase theyā€™re not efficient enough. Someone should implement a feature, which enables particles to cast shadows on other particles. and voilaā€¦ there you have the most realitstic clouds in teh world :wink:

I would start working on it, If I hadnā€™t had to learn blenders interface first. But if someone tells me this is very easy and can show me the relevant parts of the source code i would try working on it ^^

that would be good, but I think that their may be way to many variables. I am not a meterologist but i think that the reason clouds look the reason they do is because of a mixture of heat, wind, updrafts, downdrafts, pressures, temp, over land, over mountains, interacting with the jet stream, evaporation, and the butterfly in China flapping its wings. But if you could simplify it, that would be excellent. Is anyone a meterologist?