Imported existing code

indra/newview/app_settings/shaders/class2/windlight/atmosphericsF.glsl

@@ -0,0 +1,24 @@
+/** 
+ * @file atmosphericsF.glsl
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+//////////////////////////////////////////////////////////
+// The fragment shader for the terrain atmospherics
+//////////////////////////////////////////////////////////
+
+vec3 getAdditiveColor();
+vec3 getAtmosAttenuation();
+
+uniform sampler2D cloudMap;
+uniform vec4 cloud_pos_density1;
+
+vec3 atmosLighting(vec3 light)
+{
+	light *= getAtmosAttenuation().r;
+	light += getAdditiveColor();
+	return (2.0 * light);
+}
+

indra/newview/app_settings/shaders/class2/windlight/atmosphericsHelpersV.glsl

@@ -0,0 +1,41 @@
+/**
+ * @file atmosphericsHelpersV.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+// Output variables
+vec3 getSunlitColor();
+vec3 getAmblitColor();
+vec3 getAdditiveColor();
+vec3 getAtmosAttenuation();
+vec3 getPositionEye();
+
+uniform float scene_light_strength;
+
+vec3 atmosAmbient(vec3 light)
+{
+	return getAmblitColor() + light / 2.0;
+}
+
+vec3 atmosAffectDirectionalLight(float lightIntensity)
+{
+	return getSunlitColor() * lightIntensity;
+}
+
+vec3 atmosGetDiffuseSunlightColor()
+{
+	return getSunlitColor();
+}
+
+vec3 scaleDownLight(vec3 light)
+{
+	return (light / scene_light_strength );
+}
+
+vec3 scaleUpLight(vec3 light)
+{
+	return (light * scene_light_strength);
+}
+

indra/newview/app_settings/shaders/class2/windlight/atmosphericsV.glsl

@@ -0,0 +1,137 @@
+/**
+ * @file atmosphericsV.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+// varying param funcs
+void setSunlitColor(vec3 v);
+void setAmblitColor(vec3 v);
+void setAdditiveColor(vec3 v);
+void setAtmosAttenuation(vec3 v);
+void setPositionEye(vec3 v);
+
+vec3 getAdditiveColor();
+
+//varying vec4 vary_CloudUVs;
+//varying float vary_CloudDensity;
+
+// Inputs
+uniform vec4 morphFactor;
+uniform vec3 camPosLocal;
+//uniform vec4 camPosWorld;
+
+uniform vec4 lightnorm;
+uniform vec4 sunlight_color;
+uniform vec4 ambient;
+uniform vec4 blue_horizon;
+uniform vec4 blue_density;
+uniform vec4 haze_horizon;
+uniform vec4 haze_density;
+uniform vec4 cloud_shadow;
+uniform vec4 density_multiplier;
+uniform vec4 distance_multiplier;
+uniform vec4 max_y;
+uniform vec4 glow;
+
+void calcAtmospherics(vec3 inPositionEye) {
+
+	vec3 P = inPositionEye;
+	setPositionEye(P);
+	
+	//(TERRAIN) limit altitude
+	if (P.y > max_y.x) P *= (max_y.x / P.y);
+	if (P.y < -max_y.x) P *= (-max_y.x / P.y);
+
+	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 * 1.0 + vec4(haze_density.r) * 0.25) * (density_multiplier.x * max_y.x);
+		//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.r);
+	blue_weight = blue_density / temp1;
+	haze_weight = vec4(haze_density.r) / 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.x;
+
+	// Transparency (-> temp1)
+	// ATI Bugfix -- can't store temp1*temp2.z*distance_multiplier.x in a variable because the ati
+	// compiler gets confused.
+	temp1 = exp(-temp1 * temp2.z * distance_multiplier.x);
+
+	//final atmosphere attenuation factor
+	setAtmosAttenuation(temp1.rgb);
+	//vary_AtmosAttenuation = distance_multiplier / 10000.;
+	//vary_AtmosAttenuation = density_multiplier * 100.;
+	//vary_AtmosAttenuation = vec4(Plen / 100000., 0., 0., 1.);
+
+	//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.x * 0.5;
+
+	//haze color
+	setAdditiveColor(
+		vec3(blue_horizon * blue_weight * (sunlight*(1.-cloud_shadow.x) + tmpAmbient)
+	  + (haze_horizon.r * haze_weight) * (sunlight*(1.-cloud_shadow.x) * temp2.x
+		  + tmpAmbient)));
+
+	//brightness of surface both sunlight and ambient
+	setSunlitColor(vec3(sunlight * .5));
+	setAmblitColor(vec3(tmpAmbient * .25));
+	setAdditiveColor(getAdditiveColor() * vec3(1.0 - temp1));
+
+	// vary_SunlitColor = vec3(0);
+	// vary_AmblitColor = vec3(0);
+	// vary_AdditiveColor = vec4(Pn, 1.0);
+
+	/*
+	const float cloudShadowScale = 100.;
+	// Get cloud uvs for shadowing
+	vec3 cloudPos = inPositionEye + camPosWorld - cloudShadowScale / 2.;
+	vary_CloudUVs.xy = cloudPos.xz / cloudShadowScale;
+
+	// We can take uv1 and multiply it by (TerrainSpan / CloudSpan)
+//	cloudUVs *= (((worldMaxZ - worldMinZ) * 20) /40000.);
+	vary_CloudUVs *= (10000./40000.);
+
+	// Offset by sun vector * (CloudAltitude / CloudSpan)
+	vary_CloudUVs.x += tmpLightnorm.x / tmpLightnorm.y * (3000./40000.);
+	vary_CloudUVs.y += tmpLightnorm.z / tmpLightnorm.y * (3000./40000.);
+	*/
+}
+

indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsF.glsl

@@ -0,0 +1,34 @@
+/** 
+ * @file atmosphericVars.glsl
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+varying vec3 vary_PositionEye;
+
+varying vec3 vary_SunlitColor;
+varying vec3 vary_AmblitColor;
+varying vec3 vary_AdditiveColor;
+varying vec3 vary_AtmosAttenuation;
+
+vec3 getPositionEye()
+{
+	return vary_PositionEye;
+}
+vec3 getSunlitColor()
+{
+	return vary_SunlitColor;
+}
+vec3 getAmblitColor()
+{
+	return vary_AmblitColor;
+}
+vec3 getAdditiveColor()
+{
+	return vary_AdditiveColor;
+}
+vec3 getAtmosAttenuation()
+{
+	return vary_AtmosAttenuation;
+}

indra/newview/app_settings/shaders/class2/windlight/atmosphericsVarsV.glsl

@@ -0,0 +1,60 @@
+/** 
+ * @file atmosphericVars.glsl
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+varying vec3 vary_PositionEye;
+
+varying vec3 vary_SunlitColor;
+varying vec3 vary_AmblitColor;
+varying vec3 vary_AdditiveColor;
+varying vec3 vary_AtmosAttenuation;
+
+vec3 getPositionEye()
+{
+	return vary_PositionEye;
+}
+vec3 getSunlitColor()
+{
+	return vary_SunlitColor;
+}
+vec3 getAmblitColor()
+{
+	return vary_AmblitColor;
+}
+vec3 getAdditiveColor()
+{
+	return vary_AdditiveColor;
+}
+vec3 getAtmosAttenuation()
+{
+	return vary_AtmosAttenuation;
+}
+
+
+void setPositionEye(vec3 v)
+{
+	vary_PositionEye = v;
+}
+
+void setSunlitColor(vec3 v)
+{
+	vary_SunlitColor = v;
+}
+
+void setAmblitColor(vec3 v)
+{
+	vary_AmblitColor = v;
+}
+
+void setAdditiveColor(vec3 v)
+{
+	vary_AdditiveColor = v;
+}
+
+void setAtmosAttenuation(vec3 v)
+{
+	vary_AtmosAttenuation = v;
+}

indra/newview/app_settings/shaders/class2/windlight/cloudsF.glsl

@@ -0,0 +1,76 @@
+/** 
+ * @file WLCloudsF.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+/////////////////////////////////////////////////////////////////////////
+// The fragment shader for the sky
+/////////////////////////////////////////////////////////////////////////
+
+varying vec4 vary_CloudColorSun;
+varying vec4 vary_CloudColorAmbient;
+varying float vary_CloudDensity;
+
+uniform sampler2D cloud_noise_texture;
+uniform vec4 cloud_pos_density1;
+uniform vec4 cloud_pos_density2;
+uniform vec4 gamma;
+
+/// Soft clips the light with a gamma correction
+vec3 scaleSoftClip(vec3 light) {
+	//soft clip effect:
+	light = 1. - clamp(light, vec3(0.), vec3(1.));
+	light = 1. - pow(light, gamma.xxx);
+
+	return light;
+}
+
+void main()
+{
+	// Set variables
+	vec2 uv1 = gl_TexCoord[0].xy;
+	vec2 uv2 = gl_TexCoord[1].xy;
+
+	vec4 cloudColorSun = vary_CloudColorSun;
+	vec4 cloudColorAmbient = vary_CloudColorAmbient;
+	float cloudDensity = vary_CloudDensity;
+	vec2 uv3 = gl_TexCoord[2].xy;
+	vec2 uv4 = gl_TexCoord[3].xy;
+
+	// Offset texture coords
+	uv1 += cloud_pos_density1.xy;	//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
+
+
+	// Compute alpha1, the main cloud opacity
+	float alpha1 = (texture2D(cloud_noise_texture, uv1).x - 0.5) + (texture2D(cloud_noise_texture, 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;	
+
+
+	// Compute alpha2, for self shadowing effect
+	// (1 - alpha2) will later be used as percentage of incoming sunlight
+	float alpha2 = (texture2D(cloud_noise_texture, 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;	
+
+	// Combine
+	vec4 color;
+	color = (cloudColorSun*(1.-alpha2) + cloudColorAmbient);
+	color *= 2.;
+
+	/// Gamma correct for WL (soft clip effect).
+	gl_FragColor.rgb = scaleSoftClip(color.rgb);
+	gl_FragColor.a = alpha1;
+}
+

indra/newview/app_settings/shaders/class2/windlight/cloudsV.glsl

@@ -0,0 +1,163 @@
+/** 
+ * @file WLCloudsV.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+//////////////////////////////////////////////////////////////////////////
+// The vertex shader for creating the atmospheric sky
+///////////////////////////////////////////////////////////////////////////////
+
+// Output parameters
+varying vec4 vary_CloudColorSun;
+varying vec4 vary_CloudColorAmbient;
+varying float vary_CloudDensity;
+
+// Inputs
+uniform vec3 camPosLocal;
+
+uniform vec4 lightnorm;
+uniform vec4 sunlight_color;
+uniform vec4 ambient;
+uniform vec4 blue_horizon;
+uniform vec4 blue_density;
+uniform vec4 haze_horizon;
+uniform vec4 haze_density;
+
+uniform vec4 cloud_shadow;
+uniform vec4 density_multiplier;
+uniform vec4 max_y;
+
+uniform vec4 glow;
+
+uniform vec4 cloud_color;
+
+uniform vec4 cloud_scale;
+
+void main()
+{
+
+	// World / view / projection
+	gl_Position = ftransform();
+
+	gl_TexCoord[0] = gl_MultiTexCoord0;
+
+	// Get relative position
+	vec3 P = gl_Vertex.xyz - camPosLocal.xyz + vec3(0,50,0);
+
+	// Set altitude
+	if (P.y > 0.)
+	{
+		P *= (max_y.x / P.y);
+	}
+	else
+	{
+		P *= (-32000. / P.y);
+	}
+
+	// Can normalize then
+	vec3 Pn = normalize(P);
+	float  Plen = length(P);
+
+	// Initialize temp variables
+	vec4 temp1 = vec4(0.);
+	vec4 temp2 = vec4(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 * 1.0 + haze_density.x * 0.25) * (density_multiplier.x * max_y.x);
+
+	// Calculate relative weights
+	temp1 = blue_density + haze_density.x;
+	blue_weight = blue_density / temp1;
+	haze_weight = haze_density.x / temp1;
+
+	// Compute sunlight from P & lightnorm (for long rays like sky)
+	temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
+	temp2.y = 1. / temp2.y;
+	sunlight *= exp( - light_atten * temp2.y);
+
+	// Distance
+	temp2.z = Plen * density_multiplier.x;
+
+	// Transparency (-> temp1)
+	// ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
+	// compiler gets confused.
+	temp1 = exp(-temp1 * temp2.z);
+
+
+	// Compute haze glow
+	temp2.x = dot(Pn, lightnorm.xyz);
+	temp2.x = 1. - temp2.x;
+		// temp2.x is 0 at the sun and increases away from sun
+	temp2.x = max(temp2.x, .001);	
+		// 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;
+	tmpAmbient += (1. - tmpAmbient) * cloud_shadow.x * 0.5; 
+
+	// Dim sunlight by cloud shadow percentage
+	sunlight *= (1. - cloud_shadow.x);
+
+	// Haze color below cloud
+	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
+				+ (haze_horizon.r * haze_weight) * (sunlight * temp2.x + tmpAmbient)
+			 );	
+
+	// CLOUDS
+
+	sunlight = sunlight_color;
+	temp2.y = max(0., lightnorm.y * 2.);
+	temp2.y = 1. / temp2.y;
+	sunlight *= exp( - light_atten * temp2.y);
+
+	// Cloud color out
+	vary_CloudColorSun = (sunlight * temp2.x) * cloud_color;
+	vary_CloudColorAmbient = tmpAmbient * cloud_color;
+	
+	// Attenuate cloud color by atmosphere
+	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
+	vary_CloudColorSun *= temp1;
+	vary_CloudColorAmbient *= temp1;
+	vec4 oHazeColorBelowCloud = additiveColorBelowCloud * (1. - temp1);
+
+	// Make a nice cloud density based on the cloud_shadow value that was passed in.
+	vary_CloudDensity = 2. * (cloud_shadow.x - 0.25);
+
+
+	// Texture coords
+	gl_TexCoord[0] = gl_MultiTexCoord0;
+	gl_TexCoord[0].xy -= 0.5;
+	gl_TexCoord[0].xy /= cloud_scale.x;
+	gl_TexCoord[0].xy += 0.5;
+
+	gl_TexCoord[1] = gl_TexCoord[0];
+	gl_TexCoord[1].x += lightnorm.x * 0.0125;
+	gl_TexCoord[1].y += lightnorm.z * 0.0125;
+
+	gl_TexCoord[2] = gl_TexCoord[0] * 16.;
+	gl_TexCoord[3] = gl_TexCoord[1] * 16.;
+
+	// Combine these to minimize register use
+	vary_CloudColorAmbient += oHazeColorBelowCloud;
+
+	// needs this to compile on mac
+	//vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
+
+	// END CLOUDS
+}
+

indra/newview/app_settings/shaders/class2/windlight/gammaF.glsl

@@ -0,0 +1,24 @@
+/** 
+ * @file gammaF.glsl
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+uniform vec4 gamma;
+
+vec3 getAtmosAttenuation();
+
+/// Soft clips the light with a gamma correction
+vec3 scaleSoftClip(vec3 light) {
+	//soft clip effect:
+	light = 1. - clamp(light, vec3(0.), vec3(1.));
+	light = 1. - pow(light, gamma.xxx);
+
+	return light;
+}
+
+vec3 fullbrightScaleSoftClip(vec3 light) {
+	return mix(scaleSoftClip(light.rgb), light.rgb, getAtmosAttenuation());
+}
+

indra/newview/app_settings/shaders/class2/windlight/skyF.glsl

@@ -0,0 +1,41 @@
+/** 
+ * @file WLSkyF.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+/////////////////////////////////////////////////////////////////////////
+// The fragment shader for the sky
+/////////////////////////////////////////////////////////////////////////
+
+varying vec4 vary_HazeColor;
+
+uniform sampler2D cloud_noise_texture;
+uniform vec4 gamma;
+
+/// Soft clips the light with a gamma correction
+vec3 scaleSoftClip(vec3 light) {
+	//soft clip effect:
+	light = 1. - clamp(light, vec3(0.), vec3(1.));
+	light = 1. - pow(light, gamma.xxx);
+
+	return light;
+}
+
+void main()
+{
+	// Potential Fill-rate optimization.  Add cloud calculation 
+	// back in and output alpha of 0 (so that alpha culling kills 
+	// the fragment) if the sky wouldn't show up because the clouds 
+	// are fully opaque.
+
+	vec4 color;
+	color = vary_HazeColor;
+	color *= 2.;
+
+	/// Gamma correct for WL (soft clip effect).
+	gl_FragColor.rgb = scaleSoftClip(color.rgb);
+	gl_FragColor.a = 1.0;
+}
+

indra/newview/app_settings/shaders/class2/windlight/skyV.glsl

@@ -0,0 +1,138 @@
+/** 
+ * @file WLSkyV.glsl
+ *
+ * Copyright (c) 2005-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+// SKY ////////////////////////////////////////////////////////////////////////
+// The vertex shader for creating the atmospheric sky
+///////////////////////////////////////////////////////////////////////////////
+
+// Output parameters
+varying vec4 vary_HazeColor;
+
+// Inputs
+uniform vec3 camPosLocal;
+
+uniform vec4 lightnorm;
+uniform vec4 sunlight_color;
+uniform vec4 ambient;
+uniform vec4 blue_horizon;
+uniform vec4 blue_density;
+uniform vec4 haze_horizon;
+uniform vec4 haze_density;
+
+uniform vec4 cloud_shadow;
+uniform vec4 density_multiplier;
+uniform vec4 max_y;
+
+uniform vec4 glow;
+
+uniform vec4 cloud_color;
+
+uniform vec4 cloud_scale;
+
+void main()
+{
+
+	// World / view / projection
+	gl_Position = ftransform();
+	gl_TexCoord[0] = gl_MultiTexCoord0;
+
+	// Get relative position
+	vec3 P = gl_Vertex.xyz - camPosLocal.xyz + vec3(0,50,0);
+	//vec3 P = gl_Vertex.xyz + vec3(0,50,0);
+
+	// Set altitude
+	if (P.y > 0.)
+	{
+		P *= (max_y.x / P.y);
+	}
+	else
+	{
+		P *= (-32000. / P.y);
+	}
+
+	// Can normalize then
+	vec3 Pn = normalize(P);
+	float  Plen = length(P);
+
+	// Initialize temp variables
+	vec4 temp1 = vec4(0.);
+	vec4 temp2 = vec4(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 * 1.0 + haze_density.x * 0.25) * (density_multiplier.x * max_y.x);
+
+	// Calculate relative weights
+	temp1 = blue_density + haze_density.x;
+	blue_weight = blue_density / temp1;
+	haze_weight = haze_density.x / temp1;
+
+	// Compute sunlight from P & lightnorm (for long rays like sky)
+	temp2.y = max(0., max(0., Pn.y) * 1.0 + lightnorm.y );
+	temp2.y = 1. / temp2.y;
+	sunlight *= exp( - light_atten * temp2.y);
+
+	// Distance
+	temp2.z = Plen * density_multiplier.x;
+
+	// Transparency (-> temp1)
+	// ATI Bugfix -- can't store temp1*temp2.z in a variable because the ati
+	// compiler gets confused.
+	temp1 = exp(-temp1 * temp2.z);
+
+
+	// Compute haze glow
+	temp2.x = dot(Pn, lightnorm.xyz);
+	temp2.x = 1. - temp2.x;
+		// temp2.x is 0 at the sun and increases away from sun
+	temp2.x = max(temp2.x, .001);	
+		// 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;
+
+
+	// Haze color above cloud
+	vary_HazeColor = (	  blue_horizon * blue_weight * (sunlight + ambient)
+				+ (haze_horizon.r * haze_weight) * (sunlight * temp2.x + ambient)
+			 );	
+
+
+	// Increase ambient when there are more clouds
+	vec4 tmpAmbient = ambient;
+	tmpAmbient += (1. - tmpAmbient) * cloud_shadow.x * 0.5; 
+
+	// Dim sunlight by cloud shadow percentage
+	sunlight *= (1. - cloud_shadow.x);
+
+	// Haze color below cloud
+	vec4 additiveColorBelowCloud = (	  blue_horizon * blue_weight * (sunlight + tmpAmbient)
+				+ (haze_horizon.r * haze_weight) * (sunlight * temp2.x + tmpAmbient)
+			 );	
+
+	// Final atmosphere additive
+	vary_HazeColor *= (1. - temp1);
+	
+	// Attenuate cloud color by atmosphere
+	temp1 = sqrt(temp1);	//less atmos opacity (more transparency) below clouds
+
+	// At horizon, blend high altitude sky color towards the darker color below the clouds
+	vary_HazeColor += (additiveColorBelowCloud - vary_HazeColor) * (1. - sqrt(temp1));
+	
+	// won't compile on mac without this being set
+	//vary_AtmosAttenuation = vec3(0.0,0.0,0.0);
+}
+

indra/newview/app_settings/shaders/class2/windlight/transportF.glsl

@@ -0,0 +1,35 @@
+/** 
+ * @file transportF.glsl
+ *
+ * Copyright (c) 2007-$CurrentYear$, Linden Research, Inc.
+ * $License$
+ */
+
+//////////////////////////////////////////////////////////
+// The fragment shader for the terrain atmospherics
+//////////////////////////////////////////////////////////
+
+vec3 getAdditiveColor();
+vec3 getAtmosAttenuation();
+
+uniform sampler2D cloudMap;
+uniform vec4 cloud_pos_density1;
+
+vec3 atmosTransport(vec3 light) {
+	light *= getAtmosAttenuation().r;
+	light += getAdditiveColor() * 2.0;
+	return light;
+}
+
+vec3 fullbrightAtmosTransport(vec3 light) {
+	float brightness = dot(light.rgb, vec3(0.33333));
+
+	return mix(atmosTransport(light.rgb), light.rgb + getAdditiveColor().rgb, brightness * brightness);
+}
+
+vec3 fullbrightShinyAtmosTransport(vec3 light) {
+	float brightness = dot(light.rgb, vec3(0.33333));
+
+	return mix(atmosTransport(light.rgb), (light.rgb + getAdditiveColor().rgb) * (2.0 - brightness), brightness * brightness);
+}
+