Rocket Exhaust VFX breakdownfiled in creative

I used Blender (and the Cycles render engine) to make rocket exhaust VFX.

In the past, I’ve experimented with mesh-based exhaust, but that’s not a good fit for (pseudo)-photorealistic renders, and it’s hard to make it look good from all angles. For this shader, I wanted a single material that could blend seamlessly through all throttle levels and all altitudes.

Here’s what I ended up on for the renders you see here:

There are many other minor effects, such as a strong brightness boost near the nozzle, and a group of nodes that simulate severe underexpansion (simulating an engine burning in a vacuum.) But those are all just simple distortion node groups, applied to the polar coordinates.

The Method

Since most rocket engines are circular, I decided to use polar coordinates to represent the exhaust. Using Blender’s Texture Coordinate node, I use the Object coordinate to get the coordinate of the 3D point currently under evaluation. Then, I convert this to polar coordinates with a bit of math: X corresponds to distance from center, Y corresponds to angle (not currently used), and Z corresponds to distance along the engine exhaust, with positive numbers being above the nozzle exit plane, and negative numbers being below the nozzle exit plane.

Apogee SSG