So how did they do this? I know the reason rain went thru roofs and over hangs before was because it was an animated sprite that surrounded the player to create the illusion of it raining in the world. So a player would walk under the overhang and the rain would still be falling thru the structure.

So how do you think Bethesda finally fixed this (after 10 years of this being an issue in their games)?

I mean it is still basically gameboy engine. Could it be a particle effect where the particle is disabled from the game once it hits a surface?

I did notice some rain popping through the edge of roofs as I slowly moved from outside to under the roof.

But then the rain drops disappeared immediately before traveling more than a few inches under the roof.

Also, the ground got WET!

I could even see reflections of light sources on the pavement and ground as it got wet!

GOOD JOB Bethesda!

Gameboy engine, lol.

"Rain Occlusion", the new setting controls this, i believe? I haven't tried it off to see if it still rains inside without it.

Characters also get wet. It's a nice touch.

Hear, hear, the first time it rained I went indoors to test it, and yep, sure enough, no rain...But the PC/NPCs were still soaked, and raindrops still soak my power armor visor even when indoors...

BTW It's Gamebryo..:^)

So actors get wet when it rains even if they never go outside? oh well... this is still better than rain through the roof that we had for so many years.

Right ... Gamebryo, sorry, just a typo.

So are you a programmer? I am wondering how they finally were able to fix this (the basic layman's over all concept). I mean if it was simple they would have done it years ago...

Modders have managed to fix it in previous Beth games, so it isn't really a new thing.

Still appreciated, as are many of the other "mod imports" to be found in FO4.

I noticed this, too and it is nice touch to have in the game. Pavement gets wet when it rains and my character stays nice and dry indoors!

Sometimes it's the little things that make me appreciate what the developers do. Thanks Bethesda.

I don't think the rain was ever a Gamebryo thing in the past, was it? It was just a screen-space pixel shader, so nothing to do with rendering of meshes and textures... unless I'm horribly confused (wouldn't be the first time ).

I've no idea how it works now. I think mods replaced the pixel shader with a number of cubes with animated (non-colliding) meshes that looked like rain, and used trigger-boxes under roofed areas to switch off a cube of rain around the player, leaving distant cubes unaffected. But from the description above this seems a lot more precise, with the rain coming right up to the edge (or indeed, just inside the edge) of the roof, which itself is a dynamically placed thing.

I still haven't purchased Fallout 4, but I think I have a idea how it works.

Can someone go play Fallout 4 and test my idea see if it's true?

Like spookyfx.com said pay very close attention to the water droplets when it rains. I mean look very close and see if they are actually sprites or 3D.

Then see if they cast shadows at all. I'm wondering if they are real-time volumetric particles? Bethesda Softworks did say in the technology thing on Bethesda.net that Bethesda Game Studios is using volumetric fog or height fog too.

See if there are also forward lit particles.

Then if they are 3D and volumetric we might know why the rain droplets don't go through the roofs of buildings.

STALKER and other games figured this out in 2005. Bethesda is WAAAAY behind other developers on a lot of engine issues.

True, although to be fair to Bethesda, in Fallout 4 the roofs are now (in settlements) dynamically placed, so they can't use any optimisations that games with fixed structures could use. I don't know how many other games with dynamically placed roofs there are. Does anybody know?

Although, even if Bethesda have taken a tiny lead over other developers here, that doesn't exactly undo the slight embarrassment that was Skyrim (I say "slight" because the issue cropped up so rarely, with so many interiors having load doors, that I only found it immersion-breaking a couple of times).

Todd mentions in an interview that rather than being a shader, the fog is now a physical volumetric effect which uses dynamic tessellation, so that it actually moves through the world. If rain was now handled the same way, it would be straightforward to deal with object-based occlusion. Given that there is now a setting for Rain Occlusion, I assume that this is the case.

Ah yes, I knew the fog was volumetric. I thought I read that wrong on the Bethesda.net technology thing.

I'm still wondering if rain droplets are sprites though or 3D can someone look closer to them? And are particles forward lit? Do they cast their own shadows?

spookyfx.com says the rain droplets are sprites, but it would be nice to take a closer look at them, like really close when it rains.

no no no... I said the rain was sprites in their previous games.

In Oblivion some mods were made to simply turned off the rain "sprites" effect once you were detected to be under a roof or ledge. I did this myself with an invisible actor looking down at you to get line of sight. Then a fake rain would be turn on outside as you looked out the door. But the illusion rain that surrounded the player was turned off.

Very crude, but it worked. However it requires hard edits of EVERY location that this could happen in. So it would not work for new locations made by other modders unless they adopted the same idea for their locations in their mod.

In Fallout 4 to my eye it seems like the drop of rain are some kind of particle that is told to disappear once it hits geometry. But in some cases it takes a moment so the rain still; falls thru for a split second.

If the rain is all individual droplets I bet again the rain only happens around the player and not actually in the "world".

But it looks/feels more realistic now than in their past games. The Gamebryo engine could not do this because of the way geometry collisions worked (so I was told).

That is why I was wondering what they could have changed in the Gamebryo to make it work now and what new technology made this possible that they did not have before, otherwise I am sure they would have done it before now.

It could be as simple as "dynamic shelter detection", where if something above meets the collision requirements, there is to be no rain below. Checking it dynamically (where new structures have to be capable of the same feature) in a sandbox, especially in an engine where the feature didn't previously exist, normally has a negative effect on performance - hence why it doesn't usually make it in. Then again, they could have coded "rain collision" into every available structure from the beginning this time around.

Although I don't know that much about it taking place in other games, as very few games are comparable with the TES and FO series. I don't know much about this topic in general.

And way ahead on a lot of others.

I was wondering how the rain occlusion worked as well, but many games have this nowadays so I assume there is a common method. Just not sure what it is.

This is why I get annoyed when people blame every problem on the game engine. For years I have heard ignorant people say the rain issue was a game engine issue and that Bethesda would need to get a new engine if they ever expected to fix it. Once again, the Netimmerse / Gamebryo / Creation engine haters club has been proved wrong.

Render the world from a camera looking straight down, with RGB disabled. The resulting Z buffer tells you where raindrops will collide as they fall. It is essentially the same algorithm as shadow mapping except instead of light collision, you are finding raindrop collision. Bioshock, 2007. Great water effects in that game.