New Demo for Testing Unreal Engine 4 in Linux Using Vulkan

July 09, 2018

New Demo for Testing Unreal Engine 4 in Linux Using Vulkan

After posting a video about Unreal Engine 4 working on Linux yesterday, I decided to bite the bullet and release a demo project. This is a really quick, slapdash attempt at a demo. It may not run on your PC. It might crash it, or make it spontaneously burst into flames or speak in tongues or something, so there is no warranty either expressed or implied.

The demo only runs in Linux. You have two options for starting it. The first is is to locate the VulkanTest.sh file and run it without any switches. This should start the project using the OpenGL 4 renderer. This will give you a baseline of what performance looks like on using the OpenGL renderer on a reasonably complex project.

The second option is what everyone is here for: using the engine with Vulkan. The key here is to run the same VulkanTest.sh file and add the "-vulkan" switch on the command line. If it works and the demo starts, you should be running the Vulkan renderer. I've tested the demo on the AMDVLK drivers as well as the RADV/Mesa backend, and they both work, though the RADV drivers seem buggier and there are a lot of visual artifacts. I have not tested the demo using an Nvidia card.

When the demo starts up you can use the "e" key to bring up the menu. Here it will let you turn on some performance monitors such as the show fps command. It will also let you quit the demo. If you want, the regular console is available by pressing the ~ key. Edit: Also you can disable V-Sync by using the console command t.Maxfps.

In general, I am now getting about 10 FPS less using the Vulkan renderer, so I think there is probably a lot of optimization to be done on both sides. Also, the Soul Cave demo, which this demo is derived from, has some pretty heavy shaders in it, so this may be what is causing the performance deficit.