Shadow catcher, possible ? Oo

SebaSopp · October 25, 2017, 9:06am

Hey bluearc,
thanks for your input. Well I get some results with that technique. But because I have to do the SceneCapture two times per tick for two RenderTargets, this will impact the performance for my highpoly model even more. And as far as i understand it, I have to change all Materials from my normal one to a grey one (and back) per tick. I think it is easier and faster to hide the model… Or to use the Cliplane.

SebaSopp · February 20, 2018, 9:54am

Hey , I just wanted to check, if there are any news about a faster shadow catcher setup. Maybe the ARKit got a material/technique to create the shadows more efficient? (Also as far as i know it uses forward rendering…)

rasamaya · March 29, 2019, 9:30pm

Hey SebaSopp. Shadow catchers or casters are working fine with composure pipeline.

SebaSopp · April 15, 2019, 2:59pm

afaik the composure plugin only allows to create composting inside the Editor. And there you can render out videos or pics. My project has to be a stand alone application…

cchristman · January 26, 2020, 2:25pm

This should not be a chore

anonymous_user_b81f854c · March 6, 2020, 9:26pm

I highly recommend you take a look at the new Composure sample in the Epic Launcher. There is an example of a shadow catcher setup in there using proper lights. It is using the composure plugin but I also helped another person set up a shadowcatcher a few days ago without composure.

The gist of the more ‘robust’ way to do this is to instead use a white flood mesh and set that mesh to be only visible to a Scene Capture. he scene capture can be pointed down at the ground orthographically. Then you set any shadow casters to ‘cast hidden shadow’. Then you can hide them and the shadow will render onto the white shadow catcher ground.

The trick is making the shadow catcher ground not render in the main view. Technically it should be possible via the ‘owner only see’ flag, but that wasn’t working recently. So instead I just did something a bit hacky that checked if the camera vector was straight down (ie dot(CameraVector, 0,01) and check abs value), and collapsed the shadowcatcher in the vertex shader by adding negative worldposition.

Its also possible to handle that visibility problem more gracefully by manually hiding the shadow catcher every frame, then unhiding it just before the scene capture updates and then re-hiding it.

Can you go into detail with any of these, ? I tried doing the owner only see, but then it hid the shadow too.

anonymous_user_bc3ee958 · April 30, 2020, 7:31am

Could you tell more in detail about this, sir?

UElaci · August 2, 2020, 10:31am

Hey guys, so did anyone find a simple solution to do the shadowcatcher?

DanH71 · September 2, 2020, 7:34pm

Has there been any progress on a workable shadow catcher solution at all. Has Epic not implemented this yet as a Material/Plugin/ or BP?

thanks

Maxwell_77 · September 14, 2021, 10:07am

I am looking for an easy shadow catcher solution for Unreal since a year, too. I made some tests with the composure framework in the past. But it is a pain to set this up because it is really complicated.

I am also wondering that there exists no easy solution as a plug-in or as an engine feature in the meantime. It´s a pity that a shadow catcher seems to be so complcated to create in game engines.

Roman-design · January 18, 2022, 10:43am

Hi! Maybe this video is solution: Using Composure with a Backplate and HDRI | Tips & Tricks | Unreal Engine - YouTube