Hey all!

I was given this assignment and I did not know how to approach this. I had an idea of how I would've like to do it, but that didn't workout at all the way I wanted it to. What am I talking about? Check this out first and I'll tell you:


That's right!! You can make rain drops have a splash in Blender without having reactor particles. How? Dynamic paint!
Unfortunately, this is a feature that is a bit much for an easy QBT, so for those who don't know this feature, see Andrew's tutorial on making rain on a wet road, using this feature.

Now, for those who know a bit about this, let's continue. Set up a scene like Andrew's (basic surface for rain to fall on, raim emitter, canvas, brushes, etc).
Now, baking a second set of images, like the one Andrew made to simulate the splash, but this time make it's fade a lot quicker and give it a bit more surface area (in other words, make the particle brush area a bit bigger). This will tell our particles when and where to splash out.

Set up a new particle system on your surface (that receives the rain) and give it's velocity a bit of a random factor, so it sends particles in various directions (under Velocity), not just in straight lines along the local Z-axis. Give it a very short life-span of maybe 10 frames and add to the particle system an image texture (just click from the active particle system to the texture tab). Here is where you apply the second image sequence we baked.

Only set it to influence the lifetime of the particles. Setting it to density selects only a single frame and emits only from that frame's values.

Go back into your particle settings and set your amount of particles to about 1,000,000. This is to make sure you have enough particles per splash. Since our density influence doesn't work, this means even distribution over the surface and therefore less per particle collision; thus we need a higher amount of particles.

Working speed tip: Set your particle systems' display settings to be a point and not the final rendered result. It saves you hugely on speed. A good idea is to set the mesh's size to the particle, before boosting the value above 1000 particles.

Now, bake your particle system and set your render settings and see what result you get from the particles. They should now splash out wherever your brush system hits, like the above animation.

So, to recap:
- Similar scene to Andrew's, so you have a surface to receive rain and one that emits the rain
- Bake the rain particles
- Set up dynamic paint so you have around 3 systems baked to image sequences:
> Waves (form ripples in this instance)
> Paint (where the rain hits and a white dot remains for a few frames)
> Paint (larger particles than the previous, but remains for fewer frames)
- Apply the last paint system to the particles you want to use for the splashes, only on lifetime influence
- Bake the splash particles
- Apply your meshes to the particles
- Playback the animation (may be slow due to the amount of particles used)

Don't forget to share this! Don't be shy to share on Facebook what you made with this in the post's comment section!

PS, this should work in Cycles Render too.

Hope you all enjoyed this one!!!

Thank YOU!!!!!