I made a real-time volumetric space portal that's only visible from one side. It has settings like portal size, cloud forms, colors, twist and roll speed. It fades and dissapears completely when looked from the other way. The portal can be set to project another camera to allow seamless transitioning.
REALLY cool effect. Any breakdowns?
Thanks! There's a whole lot of mathematics inside the shader to create a torus with the correct UVs and using that to project a cloud texture in there with proper opacity masking based on the mathematical shape. Then I rolled that mathematically created torus to use it as UVs for the cloud texture. After all the UVs are set, I simply twisted the (0,0,0) position of volume with distance so it looks like the portal is sucking in the clouds.