Is it actually possible to visualise glass refraction with OpenGL in the viewport?

Almost positive it's not. I think you'd need one of those RTX cards with raytracing to accomplish real-time refraction.

Don't want to believe that, maybe with a custom GLSL shader? It's so simple in Unreal Engine …

frdf
Don't want to believe that, maybe with a custom GLSL shader? It's so simple in Unreal Engine …

It's not possible without multipass rendering, i.e. not gonna happen in Houdini GL

Blender EEVEE can do it.

Come on guys, it's 2020….this stuff should be easy to implement!

Yeah, EEVEE for Houdini would be awesome.
In the 18.5 presentation I saw a few OpenGL improvements which gives me some hope …

I watched the 18.5 presentation as well and it doesn't even seem close when it comes to the Viewport/OpenGL stuff. I think this would all be somewhat mitigated if Karma functioned as an IPR within the OBJ context instead of requiring to go into the Solaris context which, even a year later and with the new updates, still seems like a clunky implementation and one that many artists look at while scratching their heads.


Sorry for sounding a bit negative, but overall I found the 18.5 presentation to be quite disappointing in several ways.

frdf - are you on a mac? You probably know that the GL viewport on macs with AMD GPUs is still stuck in the dark ages. I doubt they would be getting any of the new viewport GL features announced in 18.5, let alone any of the fancy realtime GPU effects that games use.