Flood

This is my first piece for the year, and second year of dabbling with Blender. It’s inspired by a shot from South Korea last year.

The guy is made by HumGen3d, the plants from Botaniq, but everything else I modelled myself. The car is fairly clumsy, but I hope it works enough.

The rain is made via geometry nodes (huge number of instances with camera/water bounds culling), with a water droplet moving through the scene for motion blur. The rain is done in a separate pass and brought in via compositing. I had done an entire separate simulation of water splashes, rendered as impostors, and scattered across the surface of the water, but it just did not show up with the lighting, no matter what I did. Simulating via dynamic paint on the large plane of water would have been prohibitively expensive. I even tried a separate dynamic paint simulation with particles to add as a bump texture to the water, but it didn’t make enough of an impact.

I liked that this allowed for the rain near the top windows, and as it comes down to the street, to pick up the light and make the rain visible. Close to no rain is visible near the surface of the water, which drives me nuts.

There is a huge volume scatter in the atmosphere, and the water has principled volume scatter. I could not for the life of me get the same muddy water, so my rendition looks more still.

There’s a little bit of fake lighting to show what the umbrellas are, and to highlight the guy a little more. Most of the lighting is emission from textures. The image before denoising is noisy as all get out, even up to 8192 samples with loads of bounces. The compositor’s denoiser made a decent plate.


I omitted a bunch of the noisy street wiring and signage, but maybe it makes my scene too clear.

I simplified the skyline out of laziness and to give the guy on the car more focus.

I tried to align some elements to draw the eye down to the guy, and in the end, wanted a traffic light, and that made it even more explicit.

In compositing I bumped up the exposure by 0.4, and added some glare and lens distortion.

I’d be grateful for any feedback on the piece.

2 Likes

First of all, good job on completing this piece! I think it works quite well already. It has a somewhat simple style, but it works as a stylized image.

There are a few points I would like to bring.

  • The final render has a rather high lens distortion and a massive amount of dispersion. There are few cameras that would have that much dispersion in real life.

  • One of the reasons the original photo works so well is because most of the light is behind the man, allowing his dark silhouette to be obvious against the brightest light rays in the background. However, your image has lights that distract away from the character, especially the car’s lights, which are the brightest part of the image and catch the eye a lot.

  • The traffic light is a good idea, but I would move it a little so it doesn’t overlap the character’s silhouette, as that makes him a bit harder to notice.

  • The building in the background could be made more convincing easily: just remove the top row of windows and replace it with solid wall. Buildings often have a top section that looks different from the rest.

  • For the rain: if you want a water material to be visible, it needs stuff to reflect and lots of glossy bounces for internal reflections. Go in the render settings and increase the max glossy bounces (make sure the max bounces are at least as high or it will have no effect). Then, add a few wide but relatively weak emissive objects or lights off camera, to the sides of the image and behind. If you want the rain drops to reflect light, you need to simulate the city lights all around them.

  • For the noise and number of samples: this is a very difficult scene to render. The scene is largely lit by emissive materials, which are noisier than light objects and lots of them are either inset into some enclosed corner or affect just a small portion of the scene. The volumetrics also makes the scene harder to render. Those are all factors that contribute to the noise. But those things also make me think your scene would greatly benefit from path guiding. Even though you have to use the CPU for it, the render might be so much cleaner that you could use way fewer samples. You could also try rendering the fog as a separate pass and then composite it in, it would probably denoise better. If these tricks works, you could also try increasing the number of volume bounces: it would make your fog react more to the lights and your water volume brighter and more obvious.

2 Likes

Thanks very much. This is really useful advice, and verified some of my newbie assumptions. Fixing it might require me to dismantle too much, but it’s great advice to take on to future work.

Thanks again.

1 Like