DRTVWR-559 Revert skies to be very close to release and disable tone mapping when probe ambiance is zero.

Hack for desaturating legacy materials has been removed for performance and quality reasons.

Adds a new setting for auto adjusting legacy skies.  This is the PBR "opt out" button.  If disabled, legacy skies will disable tonemapping, automatic probe ambiance, and HDR/exposure.  If enabled, legacy skies will behave as if probe ambiance and HDR scale are 1.0, and ambient will be cut in half.  

HDR scale will act as a sky brightener, but will automatically adjust dynamic exposure so the sky will be properly exposed.  If you want relatively even exposure all the time, set HDR Scale to 1.0.  If you want a high range of exposures between indoor/dark areas and outdoor/bright areas, increase HDR Scale.

Also tuned up SSAO (thanks Rye!).

Reviewed with Brad.

1 files changed, 2 insertions, 1 deletions

diff --git a/indra/newview/llreflectionmapmanager.cpp b/indra/newview/llreflectionmapmanager.cpp
index 5dc93dbeb8..15d41c4161 100644
--- a/indra/newview/llreflectionmapmanager.cpp
+++ b/indra/newview/llreflectionmapmanager.cpp
@@ -915,7 +915,8 @@ void LLReflectionMapManager::updateUniforms()
     LLSettingsSky::ptr_t psky = environment.getCurrentSky();
 
     static LLCachedControl<F32> cloud_shadow_scale(gSavedSettings, "RenderCloudShadowAmbianceFactor", 0.125f);
-    F32 minimum_ambiance = psky->getTotalReflectionProbeAmbiance(cloud_shadow_scale);
+    static LLCachedControl<bool> should_auto_adjust(gSavedSettings, "RenderSkyAutoAdjustLegacy", true);
+    F32 minimum_ambiance = psky->getTotalReflectionProbeAmbiance(cloud_shadow_scale, should_auto_adjust);
 
     F32 ambscale = gCubeSnapshot && !isRadiancePass() ? 0.f : 1.f;
     F32 radscale = gCubeSnapshot && !isRadiancePass() ? 0.5f : 1.f;