The Ultimate Water Caustics Shader

[@BroSender]

Amazing Video, I have been so frustrated trying to create mostly realistic caustics that actually work underwater I've been using the built in fake caustics simulation built in to the water experimentation in UE5 but that is garbage and this tutorial definitely helped me make significantly better caustics that work in all the ways I want them to as well :) Thankyou SO MUCH for this tutorial :)

[@TechArtAlex]

Glad it helped, thanks for watching!

[@Himanshoot]

will the caustics reflect beneath the bottom surface as well....if i put the water in a glass container like an overhead swimming pool in a room?

[@TechArtAlex]

It depends on how you set the material up. If the effect is part of the water material itself, then no, it would only show up when looking through the water. But if it is a decal which is being projected over the room in question, then yes. Anywhere the decal touches should receive the effect.

[@Hotrood999]

Amazing job! Is it compatible with the panner method? I've been trying and it says they are not compatible (LWCVector2 and LWCVector3)

[@TechArtAlex]

Thanks! Yes, I have it panning in the example. To pan, just add a value*time to the texture coordinates before the texture sample. Since the coordinates are 3D (UVW) the added value also needs to be a vector 3 which is why a standard panner (vector 2) does not work.

[@medmel2160]

Well done for this one. What is the cost compared to common techniques?

[@TechArtAlex]

Great question. The full effect costs around 84 instructions. Using the volume texture alone with only the time based animation costs about the same as a flipbook alone, roughly 16 instructions.

[@ДмитрийПищалов-з5м]

tell me: where can I get Volumetric Textures?

[@TechArtAlex]

Outside of the occasional pre-made one you can find, you can usually make them using something like blender or Houdini. For the purpose of this shader, you can just use any regular looping 2D caustics flip book as if it was a volume texture.

[@Cyberex]

This looks pretty good. Any chance you can send me the shader?