This tutorial explains how to create a large sky-plane, create a sky-like material using the bhodinut 2d noise shaders and explains how to create your own variations etc. I was going through the "nebula" tutorial on the maxon site and I noticed that similar techniques could be used to create normal clouds, so I simplified it all a bit and decided to write a tutorial on it, hope you find it useful!!


Heres an example of the kinda thing you can create with this technique, several layered planes in this one with various materials on them!

Heres another, I also added a visible omni light to simulate the setting sun!

OK lets get started, first we need a large plane to drop the sky material onto, 1. click objects 2. Plane and 3. Theres the flat plane...

1. Click "scale" and scale the plane up a lot, 2. Click "move" and move the plane vertically upwards a little, then 3. use the "rotate view" icon to position the camera underneath the plane as shown above!

Ok down to the material now, 1. Click "file", 2. "New material" or use ctrl+N and a new material is created as shown.

1. Double click the material to open up its settings, 2. Give it a name, 3. UNTICK specular and 4. Click "Alpha" 5. Click here and 6. Choose "Bhodinut Channel" and choose 7. "Bhodinut 2D Noise" as you can see the material has see-through bits in it now...Premultiplied can also be ticked on as well but I forgot this time ;-)

1. Click "EDIT" and bring up the shader setting window, 2. Click here to change to different types of noise, check the next part.....

Choose "Turbulence"

1. Choose "Turbulence" as meantioned above, 2. Change the Global scale to 200% then 3. drag "low clip" up a bit and 4. "high clip" down a bit, this has a similar effect to upping the contrast and as you can see there are white cloudy bits and black parts that will be see-through cus this is the alpha map! playing with the scales, low/high clips etc will achieve different effects!

1. drag the material onto the plane name and 2. as you can see it now has the material applied to it, I did a quick render and you can already see the cloud type formations, OK now to make it a bit more interesting!

1. Click the "Alpha" channel and 2. Click here and 3. Choose COPY CHANNEL

1. Click the "Luminance" channel now and 2. Click here and choose 3. PASTE CHANNEL, also very importantly 4. set the mix to "MULTIPLY" The settings for this will be changed later because with Alpha and Luminance the same it deosn't look so good!

OK lets quickly drop a background in as well, 1 Click Objects, 2. Scene and 3. Background, this creates a background object in the scene!

Right we need a quick material now, create a new material as before and UNTICK all except "Color" 1. Click it then 2. Click here and Choose 3. "Bhodinut Channel" and choose 4. "Bhodinut Gradient" from the list.

1. Click edit to open up "Gradients" settings, 2. Choose 2D-V so the gradient goes from top to bottom instead of side to side, 3. I changed this one to blue and 4. this one to white giving a nice gradient from blue down to white, 5. Click OK, Now drag and drop this material onto the background object!!!

Right now the copy of the Alpha we pasted into the Luminance channel needs some tweaking. 1. Click Luminence and 2. Choose "Wavy Turbulence" instead and I set the scale back down to 100% then 4. I also tweaked these a bit using trial and error ;-) then 5. Click OK and do a test render...

OK the actual colours affect how the clouds look, 1. The "Colour" colour was set to dull white and 2. The "Luminance" colour was set to an orange-ish colour, by changing these colours you can achieve very different looking clouds, experiment a little!

Ok after a few test renders I wanted to change the Alpha as well (its good if its different to the Luminance channel) 1. Click "Alpha" and 2. Click EDIT, 3. I changed the scale to 200% and 4. I chose "Turbulence" and 5. I tweaked these settings and did test renders. All these settings are well worth spending a lot of time experimenting with as they allow you to achive unlimited FX.

Heres a quick render, now we wanna add some light so 1. Click Add light and 2. Choose a light 3. Set as omni(default) and 4. Turn on visible light, also 5. Choose a colour for the sunlight!

Move the light into a position at the edge of the sky-plane and set the range 1. Click Light and 2. Drag the Visible Light size from small to larger, experiment with it as it depends on what kinda sky your creating!

For quick tweaking of the clouds 1. Click the plane and 2. Click the material, 3. changing the UV tiling sets the density of the clouds, setting at 2:1 or 3:1 can make them longer and stringier etc!! Experiment. Also changing the scale/low clip/high clip etc in the Alphas settings can achieve less dense cloud formations or extremely dense ones etc.

Heres the final image! Another idea is to copy the plane and move it up a little then create a copy material, tweak its colours and scales etc and drop it onto the new plane, mixing several planes of different coloured/noise clouds can achieve some great FX......Experiment!

With a little work you can also animate the sky's quite easily, see below:-

Rolling sky video - 245kbs avi

Rolling sky with setting sun video - 245kbs avi


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