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diff --git a/indra/newview/app_settings/shaders/class3/deferred/cloudsF.glsl b/indra/newview/app_settings/shaders/class3/deferred/cloudsF.glsl
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+++ b/indra/newview/app_settings/shaders/class3/deferred/cloudsF.glsl
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+/** 
+ * @file class3/deferred/cloudsF.glsl
+ *
+ * $LicenseInfo:firstyear=2005&license=viewerlgpl$
+ * Second Life Viewer Source Code
+ * Copyright (C) 2005, 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
+ * $/LicenseInfo$
+ */
+ 
+#ifdef DEFINE_GL_FRAGCOLOR
+out vec4 frag_data[3];
+#else
+#define frag_data gl_FragData
+#endif
+
+/////////////////////////////////////////////////////////////////////////
+// The fragment shader for the sky
+/////////////////////////////////////////////////////////////////////////
+
+VARYING vec4 vary_CloudColorSun;
+VARYING vec4 vary_CloudColorAmbient;
+VARYING float vary_CloudDensity;
+VARYING vec2 vary_texcoord0;
+VARYING vec2 vary_texcoord1;
+VARYING vec2 vary_texcoord2;
+VARYING vec2 vary_texcoord3;
+VARYING vec3 vary_pos;
+
+uniform sampler2D cloud_noise_texture;
+uniform sampler2D cloud_noise_texture_next;
+uniform float blend_factor;
+uniform vec4 cloud_pos_density1;
+uniform vec4 cloud_pos_density2;
+uniform vec4 cloud_color;
+uniform float cloud_shadow;
+uniform float cloud_scale;
+uniform float cloud_variance;
+uniform vec3 camPosLocal;
+uniform vec3 sun_dir;
+uniform float sun_size;
+uniform float far_z;
+
+uniform sampler2D transmittance_texture;
+uniform sampler3D scattering_texture;
+uniform sampler3D single_mie_scattering_texture;
+uniform sampler2D irradiance_texture;
+uniform sampler2D sh_input_r;
+uniform sampler2D sh_input_g;
+uniform sampler2D sh_input_b;
+
+vec3 GetSkyLuminance(vec3 camPos, vec3 view_dir, float shadow_length, vec3 dir, out vec3 transmittance);
+
+/// Soft clips the light with a gamma correction
+vec3 scaleSoftClip(vec3 light);
+
+vec4 cloudNoise(vec2 uv)
+{
+   vec4 a = texture2D(cloud_noise_texture, uv);
+   vec4 b = texture2D(cloud_noise_texture_next, uv);
+   vec4 cloud_noise_sample = mix(a, b, blend_factor);
+   return cloud_noise_sample;
+}
+
+void main()
+{
+    // Set variables
+    vec2 uv1 = vary_texcoord0.xy;
+    vec2 uv2 = vary_texcoord1.xy;
+    vec2 uv3 = vary_texcoord2.xy;
+    float cloudDensity = 2.0 * (cloud_shadow - 0.25);
+
+    if (cloud_scale < 0.001)
+    {
+        discard;
+    }
+
+    vec2 uv4 = vary_texcoord3.xy;
+
+    vec2 disturbance = vec2(cloudNoise(uv1 / 16.0f).x, cloudNoise((uv3 + uv1) / 16.0f).x) * cloud_variance * (1.0f - cloud_scale * 0.25f);
+
+    // Offset texture coords
+    uv1 += cloud_pos_density1.xy + (disturbance * 0.2); //large texture, visible density
+    uv2 += cloud_pos_density1.xy;   //large texture, self shadow
+    uv3 += cloud_pos_density2.xy; //small texture, visible density
+    uv4 += cloud_pos_density2.xy;   //small texture, self shadow
+
+    float density_variance = min(1.0, (disturbance.x* 2.0 + disturbance.y* 2.0) * 4.0);
+
+    cloudDensity *= 1.0 - (density_variance * density_variance);
+
+    // Compute alpha1, the main cloud opacity
+    float alpha1 = (cloudNoise(uv1).x - 0.5) + (cloudNoise(uv3).x - 0.5) * cloud_pos_density2.z;
+    alpha1 = min(max(alpha1 + cloudDensity, 0.) * 10 * cloud_pos_density1.z, 1.);
+
+    // And smooth
+    alpha1 = 1. - alpha1 * alpha1;
+    alpha1 = 1. - alpha1 * alpha1;  
+
+    if (alpha1 < 0.001f)
+    {
+        discard;
+    }
+
+    // Compute alpha2, for self shadowing effect
+    // (1 - alpha2) will later be used as percentage of incoming sunlight
+    float alpha2 = (cloudNoise(uv2).x - 0.5);
+    alpha2 = min(max(alpha2 + cloudDensity, 0.) * 2.5 * cloud_pos_density1.z, 1.);
+
+    // And smooth
+    alpha2 = 1. - alpha2;
+    alpha2 = 1. - alpha2 * alpha2;  
+
+    vec3 view_ray = vary_pos.xyz + camPosLocal;
+
+    vec3 view_direction = normalize(view_ray);
+    vec3 sun_direction  = normalize(sun_dir);
+    vec3 earth_center   = vec3(0, 0, -6360.0f);
+    vec3 camPos = (camPosLocal / 1000.0f) - earth_center;
+
+    vec3 transmittance;
+    vec3 radiance_sun  = GetSkyLuminance(camPos, view_direction, 1.0 - alpha1, sun_direction, transmittance);
+
+    vec3 sun_color = vec3(1.0) - exp(-radiance_sun * 0.0001);
+
+    // Combine
+    vec4 color;
+
+    vec4 l1tap = vec4(1.0/sqrt(4*3.14159265), sqrt(3)/sqrt(4*3.14159265), sqrt(3)/sqrt(4*3.14159265), sqrt(3)/sqrt(4*3.14159265));
+
+    vec4 l1r = texture2D(sh_input_r, vec2(0,0));
+    vec4 l1g = texture2D(sh_input_g, vec2(0,0));
+    vec4 l1b = texture2D(sh_input_b, vec2(0,0));
+
+    vec3 sun_indir = vec3(-view_direction.xy, view_direction.z);
+    vec3 amb = vec3(dot(l1r, l1tap * vec4(1, sun_indir)),
+                    dot(l1g, l1tap * vec4(1, sun_indir)),
+                    dot(l1b, l1tap * vec4(1, sun_indir)));
+
+
+    amb = max(vec3(0), amb);
+
+    color.rgb = sun_color * cloud_color.rgb * (1. - alpha2);
+    color.rgb = pow(color.rgb, vec3(1.0 / 2.2));
+    color.rgb += amb;
+
+    frag_data[0] = vec4(color.rgb, alpha1);
+    frag_data[1] = vec4(0);
+    frag_data[2] = vec4(0,1,0,1);
+}
+