47
votes
Accepted
Volumetric Windows 10 logo effect
Emulate light scattering using a volumetric emission shader
Using Volumetric scatter produces the most accurate results but required a considerable number of render samples to get satisfactory ...
- 44.3k
27
votes
Accepted
Volume Gods rays are not well defined
Because your light source is too big.
God rays are just interesting/complicated shadow patterns hanging in space. If your light is throwing soft, boring shadows, the god rays of those shadows hanging ...
- 9,082
24
votes
Accepted
How to: Exponential Fall Off for Volume Density?
You can use Vector maths and Maths nodes to calculate the 'altitude' above the planet and from there the atmospheric density and use this to control the density of the Volumetric Scatter.
To achieve ...
- 44.3k
23
votes
Accepted
Create procedural spiral pattern
Final result
One method is to create a volumetric cylinder and distort it by rotating it around the origin by an amount that varies based on the distance from the origin.
First, create a volumetric ...
- 44.3k
22
votes
Accepted
Create a gradient effect, like for coffee?
This can actually be done quite easily (and efficiently) using the volume absorption shader:
You're correct that this is a volumetric effect - it's dependent on how far the light travels through the ...
- 9,082
21
votes
Accepted
Distance from the surface as an input node for use with volumetric materials
You can use an OSL shader that measures the proximity of the mesh from within a volume. It works by projecting out rays from each point in the volume to probe the surrounding mesh. Be warned that this ...
- 44.3k
19
votes
Accepted
Is there an easy way to make volumetric clouds for Cycles?
Let's use the Cloud Generator addon to make nice clouds and the new Point Density Texture to render them inside Cycles!
First enable the addon in User Preferences under Object: Cloud Generator.
...
- 50.8k
19
votes
Accepted
Question about volume samples
No, you are confusing volume samples, volume bounce depth, and ray-marching steps, which are all different controls.
To start with, a short overview of how volume rendering works. As a ray passes ...
- 9,082
17
votes
Accepted
Render semi-transparent volume with cycles
PNG images can't represent objects that emit light but not block any light, due to the way they represent transparency. For that reason, you must always have some amount of volume absorption for the ...
- 7,441
16
votes
Using image sequence of medical scans as volume data in cycles
You can use an osl shader to do that.
The code in the capture above creates an osl node. Here are its inputs and outputs :
The input slots
Vector : the mapping position (in this config, this must ...
- 53.5k
15
votes
Accepted
Using image sequence of medical scans as volume data in cycles
If you don't want to use OSL as in lemon's answer I have created a method to do this using only Cycles nodes. (Remember OSL isn't supported on GPU.) The downside to my method is that it requires the ...
- 25k
14
votes
Accepted
Creating a Fluffy Cloud
Here's what your file looks like rendered with the Sun lamp strength set to 4 (it was set to 1):
The key to having a good "fluff" is a wide dynamic range. Dynamic range is the distance between the ...
- 157k
13
votes
Accepted
How to properly render smoke on a transparent background?
It's a viewer issue only. Try compositing over a gray background using the alpha-over node.
If the result is correct, then your file output (without the gray background, of course) will be correct as ...
- 2,220
13
votes
Accepted
Why is this transparent material rendering black?
Even though you have 'Transmission' bounces set to 12 you are capping the 'Max' bounces to 4, meaning it's never doing 12 bounces. Here I have upped the 'Max' bounces to 6 and the liquid started to ...
- 29.1k
13
votes
Volumetric Windows 10 logo effect
You should look at the sunbeam node in the compositor - after render, you can add several filters and color mix nodes, but a really good way to get this effect seems to be with the sunbeam node to ...
- 8,323
12
votes
Accepted
Volume Scatter goes Black
Your cube is black because your volume scatter node is plugged into the surface input of the material output node.
From the manual page on the shader,
The Volume Shader output must be plugged into ...
- 12.3k
12
votes
Emission: Red glow while the object itself is white
If you really want to use Cycles: Add a box which encloses the entire scene, add a principled volume shader to the box and play with Density and Anisotropy:
In comp you can add a Denoise node to save ...
- 7,040
12
votes
Accepted
Emission: Red glow while the object itself is white
From a physically based rendering point of view, the problem you are running into is that Blender's HDR tone mapping is trying too hard to be helpful.
The effect you see in the reference image occurs ...
- 244
12
votes
Accepted
God Rays through window pane: Cycles
Use a cuboid to surround the scene, and use a volume scatter node as volume. Nothing shoud be connected to the surface socket.
The default value of 1 for volume scatter is way too dense for practical ...
- 13.9k
11
votes
Accepted
How to achieve white "fog" effect within an ice cube?
Here's a try using point density for the fog effect.
There are two cubes in the image, I just beveled them slightly, the outer cube's material is basically a glass setup, except that I used an image ...
- 12.3k
11
votes
Accepted
Create a trail effect (Meteor, Comet)
With current experimental build 2.91 you can base this on Volume Object.
create the shape from a Mesh Object.
add Volume Object and in modifiers choose Mesh to Volume, as source Object choose created ...
- 34.8k
11
votes
Accepted
Volumetric slicing in Blender
You can get a similar result with a Boolean modifier
Create your slicing planes (you can array them using Array modifier)
Add a Boolean Modifier > Intersect to your object
Target the slicing ...
- 31.2k
10
votes
Accepted
Colours in OpenVDB volumes
The Principled Volume shader automatically picks up some details from attributes (eg, 'density' or 'temperature' and the Blackbody input can use this to generate the volume. This means it's not ...
- 44.3k
9
votes
Accepted
Domain boxes show up in cycles render
It looks like you have a diffuse shader assigned to the surface of your domain. Make sure that there is nothing (or a pure white transparent shader) plugged into the surface socket on your domain ...
- 25k
9
votes
Accepted
Displaying airflow inside of an engine model
Smoke seems like the correct medium to display airflow. Since Blenders smoke does not support suction, you'll have to fake the flow using multiple Forcefield.
Model a simplified collider and mark it ...
- 25.8k
9
votes
Emission: Red glow while the object itself is white
That's actually quite challenging. I wonder if the maker of your reference image used some compositing.
At least I think separate lights were used for the background objects.
And to answer your ...
- 7,040
9
votes
Simulating neon: Find angle between two vectors with shader nodes
Much the same method as yours.. A geometry-bevelled curve for the glass, with a Solidify modifier to make it a tube. A duplicate of the curve, with a smaller bevel, for the gas.
The glass is just a ...
- 74.1k
Only top scored, non community-wiki answers of a minimum length are eligible