1 files changed, 113 insertions, 9 deletions
diff --git a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl b/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl
index fea3cbf69b..fee1a7f311 100644
--- a/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl
+++ b/indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl
@@ -22,23 +22,127 @@
  * Linden Research, Inc., 945 Battery Street, San Francisco, CA  94111  USA
  * $/LicenseInfo$
  */
- 
-
-
-//////////////////////////////////////////////////////////
-// The fragment shader for the terrain atmospherics
-//////////////////////////////////////////////////////////
 
 vec3 getAdditiveColor();
 vec3 getAtmosAttenuation();
 
 uniform sampler2D cloudMap;
+uniform vec4 gamma;
 uniform vec4 cloud_pos_density1;
+uniform vec4 lightnorm;
+uniform vec4 sunlight_color;
+uniform vec4 ambient;
+uniform vec4 blue_horizon;
+uniform vec4 blue_density;
+uniform float haze_horizon;
+uniform float haze_density;
+uniform float cloud_shadow;
+uniform float density_multiplier;
+uniform float distance_multiplier;
+uniform float max_y;
+uniform vec4 glow;
+uniform float scene_light_strength;
+uniform mat3 ssao_effect_mat;
 
-vec3 atmosLighting(vec3 light)
+vec3 scaleFragSoftClip(vec3 light)
+{
+	//soft clip effect:
+	light = 1. - clamp(light, vec3(0.), vec3(1.));
+	light = 1. - pow(light, gamma.xxx);
+	return light;
+}
+
+vec3 atmosFragLighting(vec3 light, vec3 additive, vec3 atten)
 {
-	light *= getAtmosAttenuation().r;
-	light += getAdditiveColor();
+	light *= atten.r;
+	light += additive;
 	return (2.0 * light);
 }
 
+vec3 atmosLighting(vec3 light)
+{
+    return atmosFragLighting(light, getAdditiveColor(), getAtmosAttenuation());
+}
+
+void calcFragAtmospherics(vec3 inPositionEye, float ambFactor, out vec3 sunlit, out vec3 amblit, out vec3 additive, out vec3 atten) {
+
+	vec3 P = inPositionEye;
+	
+	vec3 tmpLightnorm = lightnorm.xyz;
+
+	vec3 Pn = normalize(P);
+	float Plen = length(P);
+
+	vec4 temp1 = vec4(0);
+	vec3 temp2 = vec3(0);
+	vec4 blue_weight;
+	vec4 haze_weight;
+	vec4 sunlight = sunlight_color;
+	vec4 light_atten;
+
+	//sunlight attenuation effect (hue and brightness) due to atmosphere
+	//this is used later for sunlight modulation at various altitudes
+	light_atten = (blue_density + vec4(haze_density * 0.25)) * (density_multiplier * max_y);
+		//I had thought blue_density and haze_density should have equal weighting,
+		//but attenuation due to haze_density tends to seem too strong
+
+	temp1 = blue_density + vec4(haze_density);
+	blue_weight = blue_density / temp1;
+	haze_weight = vec4(haze_density) / temp1;
+
+	//(TERRAIN) compute sunlight from lightnorm only (for short rays like terrain)
+	temp2.y = max(0.0, tmpLightnorm.y);
+	temp2.y = 1. / temp2.y;
+	sunlight *= exp( - light_atten * temp2.y);
+
+	// main atmospheric scattering line integral
+	temp2.z = Plen * density_multiplier;
+
+	// Transparency (-> temp1)
+	// ATI Bugfix -- can't store temp1*temp2.z*distance_multiplier in a variable because the ati
+	// compiler gets confused.
+	temp1 = exp(-temp1 * temp2.z * distance_multiplier);
+
+	//final atmosphere attenuation factor
+	atten = temp1.rgb;
+	
+	//compute haze glow
+	//(can use temp2.x as temp because we haven't used it yet)
+	temp2.x = dot(Pn, tmpLightnorm.xyz);
+	temp2.x = 1. - temp2.x;
+		//temp2.x is 0 at the sun and increases away from sun
+	temp2.x = max(temp2.x, .03);	//was glow.y
+		//set a minimum "angle" (smaller glow.y allows tighter, brighter hotspot)
+	temp2.x *= glow.x;
+		//higher glow.x gives dimmer glow (because next step is 1 / "angle")
+	temp2.x = pow(temp2.x, glow.z);
+		//glow.z should be negative, so we're doing a sort of (1 / "angle") function
+
+	//add "minimum anti-solar illumination"
+	temp2.x += .25;
+	
+	//increase ambient when there are more clouds
+	vec4 tmpAmbient = ambient + (vec4(1.) - ambient) * cloud_shadow * 0.5;
+	
+	/*  decrease value and saturation (that in HSV, not HSL) for occluded areas
+	 * // for HSV color/geometry used here, see http://gimp-savvy.com/BOOK/index.html?node52.html
+	 * // The following line of code performs the equivalent of:
+	 * float ambAlpha = tmpAmbient.a;
+	 * float ambValue = dot(vec3(tmpAmbient), vec3(0.577)); // projection onto <1/rt(3), 1/rt(3), 1/rt(3)>, the neutral white-black axis
+	 * vec3 ambHueSat = vec3(tmpAmbient) - vec3(ambValue);
+	 * tmpAmbient = vec4(RenderSSAOEffect.valueFactor * vec3(ambValue) + RenderSSAOEffect.saturationFactor *(1.0 - ambFactor) * ambHueSat, ambAlpha);
+	 */
+	tmpAmbient = vec4(mix(ssao_effect_mat * tmpAmbient.rgb, tmpAmbient.rgb, ambFactor), tmpAmbient.a);
+
+	//haze color
+        additive =
+		vec3(blue_horizon * blue_weight * (sunlight*(1.-cloud_shadow) + tmpAmbient)
+     	          + (haze_horizon * haze_weight) * (sunlight*(1.-cloud_shadow) * temp2.x
+		  + tmpAmbient));
+
+	//brightness of surface both sunlight and ambient
+	sunlit = vec3(sunlight * .5);
+	amblit = vec3(tmpAmbient * .25);
+	additive *= vec3(1.0 - temp1);
+}
+