In this tutorial, you will create some cigarette smoke. AfterBurn is often used for big puffs of smoke, but can be very fast and effective for more wispy types of effects. For this you will be using the Octane Shader as it is very fast and lends itself to this type of effect very nicely.
This scene contains a cigarette model with particles emitting from the tip. The particle system has Wind and Drag SpaceWarps bound to it so the particles have a smoke-like motion. Now you will make these particles look like smoke at render time.
- Start up 3ds max and open the AB-tut10.max scene.
Start scene opened
- Go to > Rendering Menu > Environment or press 8 on the keyboard to bring up the Environment Panel.
- Click the Add... button in the Atmosphere Rollout and add AfterBurn. This will add both the AfterBurn effect and the FusionWorks Renderer that is always needed to render out volumetrics.
- Select AfterBurn in the Effects list and go to the AfterBurn Manager Rollout. Click on the Pick Particles/Daemons button and choose Superspray01.
AfterBurn Manager rollout with particles chosen
This adds the particle system to AfterBurn
- Click the Pick Lights button in the Source Lights section and choose spot01.
AfterBurn Manager rollout with light chosen
This adds the light to AfterBurn to illuminate the smoke.
- Do a quick render of the Camera view.
Render of smoke with default AfterBurn settings
This gives you some nice volumetrics puffs but it's not quite what we are looking for. Let's adjust some settings to get this looking more like cigarette smoke. The first thing to edit is the overall size of the volumetric puffs.
- Scroll down to the Particle Shape rollout and adjust the Sph. Radius: Low Value to 1.5. Right-click on the AFC to enable it so you can set the Hi Value to 20.
Sphere Radius adjusted
This will make it so the spherical volume starts out small and gets bigger over the particles age.
- Click the Show in Viewport button in the Display section of the AfterBurn Manager Rollout so you can see the volumetric spheres.
Spherical volumes displayed in the Viewport
Now that the size is adjusted you will lower the density and change some of the noise parameters to reduce the smokes thickness and noise. By increasing the noise size and lowering the noise levels, you will smooth out the noise pattern applied to the volumetric puffs. To see this more clearly while you work, you will turn on Interactive Update.
- Scroll down to the Noise Animation rollout and click the Interactive Update button under the preview window.
Turning on Interactive Update
- Scroll down the Noise Animation Parameters Rollout and adjust these values:
Noise Size: 15.0
Noise Type: Turbulent
Turbulent rollout / Noise levels: 1.0
When adjusting the Noise parameters you should be able to see the effects in the preview window above.
- Go to frame 300 and render.
Frame 300 render
The smoke is looking better but still needs some more tweaking. Next you will change the Density so that the smoke is thicker in the middle and trails off at the end.
- In the Noise Animation rollout right click the Density AFC and enable it. Set the Hi Value to 0.25 and open up the AFC graph by clicking the AFC button.
The default graph is a linear progression form .1 to 0.25 over the particle's life. We want the smoke to have a .1 Density at the beginning and end of its life and .25 in the middle. To do this you will just adjust the graph to look more like a half circle.
- Adjust the curve in the Graph to look like the image below by adding two points in the middle and moving the endpoints.
Adjusted Density AFC graph
- Render frame 300 and see the smoke is much thicker in the middle.
Now that we have adjusted the AFC for Density, you can do the same for the Sph. Radius.
- Scroll to the Particle Shape rollout and click on the Sph. Radius AFC button. Adjust the graph to look like the image below.
Adjusted Sph. Radius AFC graph
Now the particle volumes grow and fade in both size and density over the particle's age.
- Render frame 300 to see the result.
Next you will change the rendering type from Raymarcher to Octane Shader. The Octane Shader is much faster and better suited to thin smoke of this type.
- Scroll up to the AfterBurn Manager Rollout and choose Octane Shader from the Rendering Type dropdown, and render the scene.
- Scroll down to the Noise Animation rollout and adjust the Hi threshold to 0.5 and Lo Threshold to .1.
- This should ad some contrast to the smoke. These parameters are just like the Hi and Lo in a standard 3ds Max noise map.
To give the smoke a bit more realism when you can turn on Auto stretch. This will stretch the volumetric puffs according to the particle velocity.
- Scroll to the Particle Shape rollout and click the part. Velocity button under Alignment and set the Auto Stretch value to 10.
Try to render with and without Auto stretch so you and see the difference it adds to the animation. You might also want to play with the Seed in the AfterBurn Master Rollout a bit to get the smoke you are looking for. This is a great way to reuse a setup as a preset and not have it always look exactly the same. A Seed of 3 works well.
- Render the animation.