How to create a moonlit ocean? Movable point light causes artifacts on surface

Development Rendering
1

I’m trying to create an ocean scene at night lit by the moon. My idea is to create a movable point light with a very large attenuation radius. The problem is that I get rectangular artifacts on my test plane. If I make the light stationary the artifacts disappear, but in my case I need the moon to move.
Is there something generally wrong with my approach, or is there just a lighting setting that I need to tweak so that the artifacts disappear?

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I think I need to use a movable point light because I want accurate specular reflections on the water surface, and the water surface should be lit dynamically by the moon. Is the correct approach?
I don’t think a directional light will work for me, since I want to achieve an effect similar to these reference images:

2

Directional light is the way to go. Point light wont give the desired effect in long distance.

3

In my project I used two separate DirectionalLightSource’s as my sun and moon light and it works great.
The second reference image is easily achievable with setup. :slight_smile:

4

First: The moon should be a directional light source, not point light. The moon is “infinitely” far away, like the sun is.
Second: Those artifacts could be many things. Bad normal maps, bad geometry, too low light map resolution, graphics driver bugs, bad shaders, …
You’ll have to experiment a little more to see what’s causing them.