Rendering from the Command Line

It is possible to render a FLIP Fluids simulation from the command line without opening the Blender interface. This document will detail how to render your .blend file from the command line. You will need to have basic knowledge of how to use your OS command line utility to follow this document.

Rendering from the command line has been found to be the most stable way to render large amounts of simulation data and can prevent crashes, issues involving missing transformations and incorrect display, and other odd rendering behavior.

The FLIP Fluids Helper > Command Line Tools menu can help you automatically set up command line rendering or baking.

Automatically Starting a Command Line Render

The FLIP Fluids addon contains command line tool operators to automatically launch a command line window to start rendering the animation.

1. Save your .blend file
2. Open the FLIP Fluids sidebar helper menu (Hotkey N).
3. In the Command Line Tools section, click the Launch Render operator.

Manually Starting a Command Line Render

This method will render your .blend file exactly as if you had pressed the Animation operator within the Blender render properties panel.

To begin an animation render, open your command line utility and run the following command:

blender -b file.blend -a

Your render should now be running! Blender will display animation progress to the command line.

Example Command

Here is an example of how to use the command in the above section on the Windows operating system using CMD. Let's assume that:

1. Your Blender executable is located here:
   C:\Program Files\Blender Foundation\Blender\blender.exe
2. Your scene file is located here:
   C:\Users\Ryan\Documents\my_simulation.blend

Then your fully formed command to render the scene would be:

"C:\Program Files\Blender Foundation\Blender\blender.exe" -b "C:\Users\Ryan\Documents\my_simulation.blend" -a

Related Links

• For instructions on how to bake a simulation from the command line, see this document: Baking from the Command Line.
• For more information on using Blender from the command line, see the Blender Command Line documentation.
• Article by Tudor Nikolav: Blender – improve render stability 100% by rendering from the command line.