In this tutorial you will learn how to glow AfterBurn rocket exhaust.
- In 3ds Max, select File->Open, and from your /Scenes/AfterBurn/Tutorials folder, select the file AB-Tut8.max.
When the file loads, scroll the Time Slider. Zoom! You see the rocket fly past you, spewing a stream of particles behind it.
If you examine the existing AfterBurn atmospheric, you'll see that under Source Particles/Daemons, the Snow01 emitter (attached to the Rocket's tail) is picked, and the Omni04 light is in the Source Lights box.
NOTE: You should also notice that we have used the Octane Shader. This is because the rocket smoke is built out of 800 particles and we want it to render quickly.
- In the Atmosphere->Effects field, click on the FusionWorks Renderer entry and check the Create Image Channels checkbox and then Material ID and Particle Age checkbox. You must use this option to apply any of the 3ds Max program's Rendering Effects or Video Post filter effects to AfterBurn. Particle Age channel is required by AfterBurn Glow effect to be able to interpolate values by using AFFs.
- Go to Rendering->Rendering Effects dialog and within the Effects rollout, click Add.
- From the resulting dialog, choose AfterBurn Glow and click OK to add it to the effects list.
Note that most of the parameters have a birth (Low) value and a death (High) value. This is because the AfterBurn Glow can apply glowing effects based on the particle age.
- Set the Low Size value to 17.0, and the High Size value to 10.0.
- Set the Low Strength spinner to 0.2 and the High Strength spinner to 0.1.
- Left-click on the Strength AfterBurn Flow Function (AFF) button to open it and set the High Clip value to 0.5.
You use the AFF to control how the Birth and Death values will be interpolated over the particle age. The Low and High Clip values define the time interval over which the interpolation occurs. With High Clip set to 0.5 and the Snow01 emitter Particle Age set to 100, all particles will be "glowed" with some Glow Strength until the age of 50 is reached (0.5*100). For any older particles, Afterburn Glow assume that the Strength is 0.0.
- Click OK to close the AFF dialog box.
- In the AfterBurn Glow Parameters rollout, make sure the Source Channel value is set to 2 and that the Color option set to Material.
The Channel value has to correspond with the AfterBurn Material ID, and the Color option will pull the glow color from the AfterBurn effect itself.
- Scrub the frame slider to frame 90, and then render the Camera01 viewport.
If you look at the Material ID of the resulting render, you'll see that their are two MatIDs being produced by the AfterBurn atmospheric, as shown below (ID 1 is in pink, and ID 2 is in green). This kind of control is critical in creating believable explosions where you only want the hot center of the volumetric effect to glow as if on fire, while the smoke around it does not.
To set the Material IDs for each portion of the AfterBurn effect, you should go to the Color Parameters rollout and set the MatID spinners to the appropriate setting.