After the horribly rainy day its been today I figured I was “feeling the physics” as Gilland said, so thought I’d make some rain. I started off with a tutorial that showed me how to make a refractive material. I made a texture with alpha that was a kind of fuzzy raindrop shape. This went into the opacity, while it was multiplied by itself and then one minused for the refraction. What this did was create a stronger, more contrasted version of the texture, then all the values were turned negative so that the most see though areas will be the most refractive. Metallic was set to 1, to give a shiney, reflective style to the material. Roughness was set to 0.01, making it very smooth. This means that you get a mirror like reflection from the surface, with a sharp reflection and tight specular highlight.
The emitter for the dripping water was a fairly simple set of particles that stream with a downwards velocity. The couple of points of note would be the use of PSA Velocity, to keep the particles facing the camera and player movement at all times, and the use of the light module, to add some additional specularity.
Its quite hard to see in stills but this is how it was looking at this point. (You can just about see the distortion in the tiles)
I then needed to create the splash at the bottom. This was similar emitter that had a cone velocity and velocity over life that started high and dropped over about 3 seconds.
So at this point I have a water fx – but it is not particularly inspired. This was really just learning about the tech that drives it.