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, 55 insertions, 0 deletions

diff --git a/indra/newview/app_settings/shaders/class1/windlight/gammaF.glsl b/indra/newview/app_settings/shaders/class1/windlight/gammaF.glsl
new file mode 100644
index 0000000000..027bfb866f
--- /dev/null
+++ b/indra/newview/app_settings/shaders/class1/windlight/gammaF.glsl
@@ -0,0 +1,55 @@
+/** 
+ * @file class2\wl\gammaF.glsl
+ *
+ * $LicenseInfo:firstyear=2007&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2007, Linden Research, Inc.
+ * 
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation;
+ * version 2.1 of the License only.
+ * 
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ * 
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
+ * 
+ * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
+ * $/LicenseInfo$
+ */
+
+ // DEPRECATED
+
+//soft clip effect has been moved to postDeferredGammaCorrect legacyGamma, this file is effectively dead
+// but these functions need to be removed from all existing shaders before removing this file
+
+vec3 scaleSoftClipFrag(vec3 light)
+{
+    return light;
+}
+
+vec3 scaleSoftClipFragLinear(vec3 light)
+{ // identical to non-linear version and that's probably close enough
+    return light;
+}
+
+vec3 scaleSoftClip(vec3 light)
+{
+    return light;
+}
+
+vec3 fullbrightScaleSoftClipFrag(vec3 light, vec3 add, vec3 atten)
+{
+    return light;
+}
+
+vec3 fullbrightScaleSoftClip(vec3 light)
+{
+    return light;
+}
+