Allow running the game with less visual detail to improve performance on lower-end machines

[unfa]

Ideas:

Scaling down Particle amount.
Simplifying shaders.
Reducing draw distance
Disabling dynamic shadows
Disabling postprocessing (bloom, SSAO, tonemapping etc.)

[xard-dev]

Also rendering on less than native resolution can help on fullscreen.

This can be quickly tested with editor by setting following parameters in editor:
Project Settings > Display > Window

• Mode = viewport
• Test Width = rendering pixel width
• Test Height = rendering pixel height

[xard-dev]

On higher resolutions (like 4k) the Screen Space reflections create a very heavy performance hit. When turned off water and glass surfaces lose reflectivity but I guess that's nothing which wouldn't be fixable using a cube envmap.

[unfa]

Hmm. The problem with Reflection Probes (which render cubemaps) is that their results cannot be cached, so when they are spawned in the game, they freeze the game for a while while they render their stuff. I wish I could cache their data and avoid that, but I haven't found a way to do so.