Cycles vs. Cycles X: Blender 3.0’s Experimental Engine

by Render Pool

September 29, 2021

As of April 2021, It has been 10 years since Blender’s flagship physically-based, ray-tracing rendering engine Blender Cycles was officially announced to undergo development.

As the core development team continued to refine and master their work, they released daily builds that reflected the technology and development of the Blender software and just recently, the experimental Blender 3.0 Alpha was released. Though the official release is still a few months away, the main draw for the new build is the 10th anniversary celebration of the Cycles rendering engine and the introduction of the Cycles X engine, which is considered to be several times faster than the current Cycles engine found in official Blender builds, including the most recent 2.93 release.

Cycles vs. Cycles X

Though we have talked at length about the differences between Cycles and Eevee, Cycles X still maintains all the impressive physically-based, photo-realistic qualities that Cycles provides, but with greater rendering speed and a smoother real-time interface.

With the new architecture in this rendering engine, it boasts a rendering speed up to 10 times faster than the current Cycles build. According to the results provided by the developers in their developer’s blog, the performance comparisons were extremely drastic. The most noticeable improvements were in interior scenes with powerful lighting that led to multiple light bounces. While Cycles X’s CPU rendering performance seems to match current results, GPU rendering performance is incredibly superior.

They have also mentioned working tirelessly to improve the real-time interactivity in the rendered viewport mode of Blender. Obviously, faster final renders are taking top priority in the development of the engine, but they also want to enhance live viewport rendering by adding support for adaptive sampling and batching samples in real-time, thereby matching the speed and beauty that Eevee is capable of providing.

How to Download Cycles X

At Blender’s official website, going to the download section in the builder page will allow you to view the most recent official builds available to users. From here, scroll down to where you can “Go Experimental” and find the experimental builds.

Once there, you may still not be able to see the Cycles X download as this page will lead you to the Daily Builds page. Though experimental, these builds are still slightly more comprehensive and are the most updated versions of testing builds. To access Cycles X, you need to go to the “Branch” sub-menu (formerly labeled “Experimental”) located above in the menu provided. Here, you will find a list of the most recent experimental releases, as well as the Cycles X build. Click on your desired build to download it.

Now, it should go without saying the following list of builds found here are experimental and though they do offer early access to new features that may potentially appear in official Blender releases in the future, they are by no means complete nor are they stable in their application.

This experimental build will download as a .zip file, so you will need to extract it in order to open it. Once you have done that, you will have a folder that has its own version of Blender inside that can be used as a supplemental rendering engine.

It should open as would any version of Blender, but with the Cycles X technology available. Open it up and give it a try. Also, do not worry about having to install or update anything new to your regular Blender software. Like other third-party dev builds of other render engines like Octane, all the architecture for the Cycles X build of 3.0 is built into the source code, and the user interface is still Blender, so don’t feel intimidated. Take the opportunity to experiment and explore.

It is recommended by the Blender core development team to use caution as this build (as well as all builds found here) can potentially corrupt your files, so use at your own risk. It is also greatly suggested that you would first produce and save your scenes in a stable version of Blender (2.8x or 2.9x) and load them in the Cycles X dev build of the program separately, then you can experiment ways to get much faster renders without the risk of losing any work.

Blender’s Cycles Will Continue to Change

As Cycles X is still under development, there are many behaviors that have not been refined or even implemented yet in the new engine, such as more sophisticated processes like volume rendering, though it is expected to change as the 3.0 build is prepped for official release in the coming months.

Along with volume, further optimization and implementation is also expected to be announced and developed as well, including Shadow Catcher AOV usage and multi-device rendering. As they add, they are also expected to take away. This includes branched path tracing, since they are working on improving the pre-existing algorithms to increase the speed of the sampling of light paths from the scene’s camera.

As this version of Cycles grows in development, we will keep you up to date on its progress and share as much new information as we can provide. Happy rendering!