View Full Version : Looking for ideas for rain...

03-12-2009, 01:04 AM
I am trying to make a level that will have a section of rain in it. The problem is that I am having trouble coming up with a good solution

The best one I have come up with so far has been with a dark matter bar covered in emitters that kick out paintballs... They don't hurt you, but they definitely interact with your character, giving it a really real feeling...

The problem is that it eats up the thermometer like nobody's business.

Any thoughts?

03-12-2009, 09:29 AM
Okay, here are my thoughts:
Create a lot of paintballs around the size of your "section" and collect them as 1 object. then use 1 or 2 emitters.

To keep your thermo from going too crazy, make the player stick to 1 or 2 planes, and only emit on those planes.

Also, raise the speed of the paintballs, and lower the lifetime.

Use a camera to limit the field of view, and make your emitters closer to the ground, to further lower the lifetime.

For longer sections, use a proximity sensor to activate the rain on the next emitter before the camera reaches that area.

Also, you dont need as many paintballs as you think. Go with quite a few less, and use the rain, and thunder and wind sound effects to help with the realism.

For added realism, use 2 emitters, with different groups of paintballs, and make them alternate their emission using the sync option.

Hope this helps!

03-16-2009, 01:59 PM
if you want a pre-made rain/lightning generator, search for "Rain/Lightning Generator" by C---Box (might have less hyphens)

03-17-2009, 01:41 PM
I am actually working at the exact same problem. My current solution is a lot of emitters that emit one object, that consists of 5 raindrops made of glass in drop shape. Than i copied the emitter along a dark matter line and changed the settings for how fast they are emitted.

The problems that do occur, is that the drops will hit on the floor and make a loud noise. You can tweak the lifetime so it won't happen, but in an online game you will have the loud noise again due to ping issues. I found my solution good so far, but it could be better.

What I thought about but have not tried yet, is a board of white glass in the background (thin layer) falling down behind the scene. On the glass I have stickers of raindrops. This way i only have to emit the falling glass (a lot fewer emitters) and you can pretty much arrange the drops on the glass as you like, so it looks more randomly than you can ever make it with emitters. I do not know if the glass looks stupid but i'd give it a shot.

Another way of avoiding the noise issue, would be to take a complete seperate layer (the one in the background) so the drops fall behind the scene and cannot make any sound at all, but this might not be possible in every level.

If you want, you can add me to your friends list and I show you what I am working on.

03-17-2009, 10:40 PM
Cool. I am having the most success with paint so far. It has a nice sound when it hits, and it splats, and your sack interacts with it.

I have discovered that I can make a section of emitters for the rain, and it isn't so bad. I was using individual emitters for individual drops, rather than capturing a lot of drops and using one emitter. Not sure which works better.

The problem is that as soon as you make it an object and try to use more than one, forget it. You are going to get a lot of problems.

The level I am working on is based off old black and white horror movies. So before my sack gets to the castle he is trying to get into, it will start to rain.

It is mostly my thermo I am worried about.

BTW, using the drop shape will use a lot more of your thermo than using a round shape. Just more corners I guess.

I will add you to my friends when I get home.

The glass idea with the stickers might be a decent idea.

03-18-2009, 09:51 AM
I had another idea today. How about making long line shaped glass things like on this picture.


That should look a lot better than drops or circles and use less polygons. You could even make them rectangle, since they are quite small and moving no one could really recognize.

I did not get around yesterday to play around but I need to try a few ideas i have to make ther ain look just perfect.

03-19-2009, 08:41 AM
Alright, first sorry for the double post but you need to see this:

I spend some time yesterday experimenting with possible ways to make rain, here are my results:

1. Approach: Dropping raindrops (drop shaped glass on the thin layer)

This looks very comically and cute which does fit the LBP universe. The downside is, that there is no reasonable or easy way to set the emitters up so it looks not awkward, since you will always have distinctive "holes" in the rain forming a pattern, i just does not look like a constant flow of raindrops from the sky. The impact on the thermo is aceptable.

Conclusion: a possible solution, delivering the look and feel, but it does not look right and is a lot of work to tweak with an impact on the thermo that is acceptable but "just" for rain maybe a little too much.

2. Approach: Dropping rectangles (good height, small width)

This looks simply amazing! If you play around with the velocity this looks pretty awsome and fits the rain feeling spot on! Really worth seeing but ... the little downside is ... well ... for one(!) emitter emitting a set of these raindrops you lose .... hold your breath ... one third of your thermo :kz:. I am not kidding you. To make a short area of awsome rain your thermo would be FULL. I guess this is because of the free floating objects, that count as physics objects, that are all made out of glass (alpha channel) and in motion and this heats the thermo pretty well.

Conclusion: Really amazing for a technical demo and show off, but way to expensive for a real level. A shame.

3. Approach: Dropping one rectangle with small rectangle cut out (inverted version of second approach)

So what I did, i basically made one object out of the many small rectangles which counted the free floating objects down a LOT. The heat on the thermo was way better (but still some impact). It still looks pretty well but only at high velocity otherwise you SEE that it is one object instead of a lot single ones. And with the high velocity you get the problem from the first approach ... you see the break between the objects that form a pattern in the rain that make it look a little awkward ... makes it look "made". Another problem is, that the one object you are dropping is limited by the "this object is too complicated" message.

Conclusion: Still a very beautiful solution and the useable alternative to approach 2 but has the downside of the pattern and some impact on the thermo (too complex objects).

4. Approach: moving two planes of glass against each other (see picture)

This is the very best of those I tried. What I did was making one high rectangle of glass on the thin layer, sticker it with blue dots until the "maximum number of stickers on one object" message appears (didn't know there is a limit but unfortunately there is) and put it on a piston moving up and down very fast. Then I copied this very layer and moved it one thin layer up front and made the same up and down movement only exactly oposite, so that one layer goes up, one goes down. On my picture you can see how i build it, you have to sacrifice the back layer and the two thin layers to make this work. On the other layers you can build the level.
Some tweaking of the pistons (for example the movement should not be exact the same, the should be slightly off so the turning point is not visible so good), some changes in lightning of the level (night, some fog) and it looks really well. The two layers moving the opposite direction uses a problem of the human eye, that cannot distinguish the real movement when two layers move very fast in opposite directions (you can see it when a car wheel is turning very fast, at one point you think it is turning in the opposite direction). Than the human brain jumps in and thinks "rain is falling down" and you think, you can see drops falling. Looks really good and takes up almost no thermo because we do not have emitters and the object is not complex and the number of objects very limited.

Conclusion: From the things I tried I absolutely prefer the last one (hence the picture) because it is the best look for almost no thermo.

I am working on a techdemo I want to release right now where I will show the different types of rain (if I can fit them in the thermo) and offer the last solution as a price bubble.

03-20-2009, 04:25 AM
I can't wait to see a sample of your plan...

I got rain to look pretty good with paintballs. It is only a small section, but works well. it does give me a message on the level that my level is starting too complicated in a small area and should spread it out.. but it doesn't stop me.

03-20-2009, 06:51 AM
Paintballs ... nice idea, have to try this one, too.

I didn' come around my level yesterday but will do so this weekend. I drop you a message when I published it.

03-20-2009, 02:48 PM
Awesome! I can't wait. I am hoping my level will be up in a few days.

I can't wait to see what you have come up with.

03-21-2009, 02:22 PM
Alright ... I reworked my last approach again because I realized that using 2 planes does smoothen the effect but it is not necessary. I also made the dots on the planes bigger so I do not need so many stickers. Because when copying the rain effect after 4 copies or so the thermo heats up pretty fast because of all the stickers.

I published a Tech Demo called "Techdemo: Rain and Thunder" please check it out. It got a prize bubble with the technique in it or you can copy the whole level if you like.

Wonko the Sane
03-21-2009, 03:03 PM
One time, I powered a watermill with what had to look like a waterfall. If you need a real rainstorm, I suggest trying rectangles of snowpaper emitted a bit slanted to one side and at a certain speed. The don't make any noise when they hit the floor and vanish in a flurry of white dust which looks very spectacular.

03-21-2009, 04:58 PM
Do you have the name of the level where you use that?

Wonko the Sane
03-21-2009, 05:56 PM
I never released it. It didn't come out very well, but that has nothing to with the waterfall though.

03-21-2009, 08:42 PM
If you could seperate it and release some kind of demo, that would be great.