Environmental Visual Enhancements Redux CKAN

This is a build of EVE which improves performance. FPS can improve anywhere from +20% to +200% based on clouds config and PC specs, check the forum thread for performance comparisons: https://forum.kerbalspaceprogram.com/index.php?/topic/196411-19-111x-eve-redux-performance-enhanced-eve-build-v11121-31012021/

A few modern rendering tricks are used to improve performance:

• Cloud shadows are rendered using the depth buffer instead of re-rendering most of the scene's geometry with a projector (saves a lot of CPU time, culling the scene+sending draw calls)

• Celestial shadows are also rendered using the depth buffer instead of re-rendering most of the scene's geometry with a projector (saves a lot of CPU time, culling the scene+sending draw calls)

• All the particles in a volumetric cloud layer are rendered at once in a single draw-call, instead of one draw-call per particle, saving CPU time

• One MeshRenderer and one GameObject per volumetric layer instead of one per particle

• Volumetric particles are rendered at 1/4 the screen resolution then upsampled with a depth-aware filter and composited into the scene, saving GPU power