Water shader

[lmoureaux]

I'd like to admire the Sun being reflected by animated waves.

This can be either vertex+fragment or fragment only. Rivers could use the same logic without waves.

[ghost]

I have added a water shader based on the Three.js webgl_shaders_ocean example: https://threejs.org/examples/webgl_shaders_ocean.html

It is only available to the high quality graphics setting since it will require a good graphics card.

https://github.com/freeciv/freeciv-web/commit/67458bdf0ffc88ef9bbe9dfcf579d9a96bd98f4e

I'm leaving this issue open still, as there could be some tuning and improvements to be made to the water shader still. Perhaps you have some suggestions Louis?

[lmoureaux]

• Maybe we could test medium quality without mirrors. But I don't fully understand how it works...
• At low quality, we could use a tiled normal map, and pass some dynamic offset as an uniform. Or even two maps (map + same map, rotated?) with offsets going in different directions to make it less monotonic.

Is it CPU- or GPU-bound ?

[ghost]

The current rendering in Freeciv-web WebGL is limited by the CPU (one core is running on 100%) on my computer. I'm not sure how to monitor GPU-usage. Perhaps I'll implement some kind of way to benchmark the WebGL performance in Freeciv-web so we can compare the performance impact of various rendering features.

[lmoureaux]

On Linux with Intel IGPs, you can use intel-gpu-tools (run the tools as root). GPU vendors make various programs for Windows.

[ghost]

CPU usage is 100% on one core, while GPU usage is never more than 35%, when testing the game on high quality, on Windows 10 with a NVIDIA GeForce GTX 780 Ti graphics card at 3840x2160. So the game is definitely CPU-bound. It runs in JavaScript in a browser after all. Perhaps some profiling can find things to improve.

[lmoureaux]

Closing this because we have a great water shader now. Performance discussion goes to #56. #57 opened about shader for lower resolutions.