Horizon blur and noise modulation model based on aloft visibility and weather variability for Atmospheric Light Scattering
This commit is contained in:
Thorsten Renk
parent
f1bee8b5ab
commit
bdd9520ca5
3 changed files with 348 additions and 315 deletions
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@ -4,16 +4,17 @@
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<parameters>
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<mie><use>/sim/rendering/mie</use></mie>
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<rayleigh><use>/sim/rendering/rayleigh</use></rayleigh>
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<density><use>/sim/rendering/dome-density</use></density>
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<overcast><use>/rendering/scene/overcast</use></overcast>
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<saturation><use>/rendering/scene/saturation</use></saturation>
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<scattering><use>/rendering/scene/scattering</use></scattering>
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<visibility><use>/environment/ground-visibility-m</use></visibility>
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<avisibility><use>/environment/visibility-m</use></avisibility>
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<lthickness><use>/environment/ground-haze-thickness-m</use></lthickness>
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<terminator><use>/environment/terminator-relative-position-m</use></terminator>
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<terrain_alt><use>/environment/mean-terrain-elevation-m</use></terrain_alt>
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<density><use>/sim/rendering/dome-density</use></density>
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<overcast><use>/rendering/scene/overcast</use></overcast>
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<saturation><use>/rendering/scene/saturation</use></saturation>
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<scattering><use>/rendering/scene/scattering</use></scattering>
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<visibility><use>/environment/ground-visibility-m</use></visibility>
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<avisibility><use>/environment/visibility-m</use></avisibility>
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<lthickness><use>/environment/ground-haze-thickness-m</use></lthickness>
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<terminator><use>/environment/terminator-relative-position-m</use></terminator>
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<terrain_alt><use>/environment/mean-terrain-elevation-m</use></terrain_alt>
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<cloud_self_shading><use>/environment/cloud-self-shading</use></cloud_self_shading>
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<horizon_roughness><use>/local-weather/config/small-scale-persistence</use></horizon_roughness>
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</parameters>
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<technique n="8">
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<predicate>
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@ -56,52 +57,57 @@
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<name>density</name>
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<type>float</type>
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<value><use>density</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>overcast</name>
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<type>float</type>
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<value><use>overcast</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>saturation</name>
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<type>float</type>
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<value><use>saturation</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>scattering</name>
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<type>float</type>
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<value><use>scattering</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>visibility</name>
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<type>float</type>
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<value><use>visibility</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>hazeLayerAltitude</name>
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<type>float</type>
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<value><use>lthickness</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>terminator</name>
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<type>float</type>
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<value><use>terminator</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>avisibility</name>
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<type>float</type>
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<value><use>avisibility</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>terrain_alt</name>
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<type>float</type>
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<value><use>terrain_alt</use></value>
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</uniform>
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</uniform>
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<uniform>
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<name>cloud_self_shading</name>
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<type>float</type>
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<value><use>cloud_self_shading</use></value>
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</uniform>
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<uniform>
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<name>horizon_roughness</name>
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<type>float</type>
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<value><use>horizon_roughness</use></value>
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</uniform>
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</pass>
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</technique>
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@ -2,27 +2,28 @@
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// Atmospheric scattering shader for flightgear
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// Written by Lauri Peltonen (Zan)
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// Implementation of O'Neil's algorithm
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// Implementation of O'Neil's algorithm
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// Ground haze layer added by Thorsten Renk
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varying vec3 rayleigh;
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varying vec3 mie;
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varying vec3 eye;
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varying vec3 hazeColor;
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varying float ct;
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//varying float cosphi;
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varying float delta_z;
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varying float alt;
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varying vec3 eye;
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varying vec3 hazeColor;
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varying float ct;
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varying float cphi;
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varying float delta_z;
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varying float alt;
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varying float earthShade;
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uniform float overcast;
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uniform float saturation;
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uniform float visibility;
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uniform float avisibility;
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uniform float scattering;
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uniform float cloud_self_shading;
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const float EarthRadius = 5800000.0;
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uniform float overcast;
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uniform float saturation;
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uniform float visibility;
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uniform float avisibility;
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uniform float scattering;
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uniform float cloud_self_shading;
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uniform float horizon_roughness;
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const float EarthRadius = 5800000.0;
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float miePhase(in float cosTheta, in float g)
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{
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@ -41,172 +42,215 @@ float rayleighPhase(in float cosTheta)
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return 1.5 * (2.0 + 0.5*cosTheta*cosTheta);
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}
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float rand2D(in vec2 co){
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return fract(sin(dot(co.xy ,vec2(12.9898,78.233))) * 43758.5453);
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}
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float simple_interpolate(in float a, in float b, in float x)
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{
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return a + smoothstep(0.0,1.0,x) * (b-a);
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}
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float interpolatedNoise2D(in float x, in float y)
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{
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float integer_x = x - fract(x);
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float fractional_x = x - integer_x;
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float integer_y = y - fract(y);
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float fractional_y = y - integer_y;
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float v1 = rand2D(vec2(integer_x, integer_y));
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float v2 = rand2D(vec2(integer_x+1.0, integer_y));
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float v3 = rand2D(vec2(integer_x, integer_y+1.0));
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float v4 = rand2D(vec2(integer_x+1.0, integer_y +1.0));
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float i1 = simple_interpolate(v1 , v2 , fractional_x);
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float i2 = simple_interpolate(v3 , v4 , fractional_x);
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return simple_interpolate(i1 , i2 , fractional_y);
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}
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float Noise2D(in vec2 coord, in float wavelength)
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{
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return interpolatedNoise2D(coord.x/wavelength, coord.y/wavelength);
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}
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void main()
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{
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{
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vec3 shadedFogColor = vec3(0.65, 0.67, 0.78);
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float cosTheta = dot(normalize(eye), gl_LightSource[0].position.xyz);
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// position of the horizon line
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float lAltitude = alt + delta_z;
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float radiusEye = EarthRadius + alt;
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float radiusLayer = EarthRadius + lAltitude;
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float cthorizon;
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float ctterrain;
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if (radiusEye > radiusLayer) cthorizon = -sqrt(radiusEye * radiusEye - radiusLayer * radiusLayer)/radiusEye;
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else cthorizon = sqrt(radiusLayer * radiusLayer - radiusEye * radiusEye)/radiusLayer;
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ctterrain = -sqrt(radiusEye * radiusEye - EarthRadius * EarthRadius)/radiusEye;
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// position of the horizon line
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float lAltitude = alt + delta_z;
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float radiusEye = EarthRadius + alt;
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float radiusLayer = EarthRadius + lAltitude;
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float cthorizon;
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float ctterrain;
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if (radiusEye > radiusLayer) cthorizon = -sqrt(radiusEye * radiusEye - radiusLayer * radiusLayer)/radiusEye;
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else cthorizon = sqrt(radiusLayer * radiusLayer - radiusEye * radiusEye)/radiusLayer;
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ctterrain = -sqrt(radiusEye * radiusEye - EarthRadius * EarthRadius)/radiusEye;
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vec3 color = rayleigh * rayleighPhase(cosTheta);
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color += mie * miePhase(cosTheta, -0.8);
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vec3 black = vec3(0.0,0.0,0.0);
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float ovc = overcast;
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float sat = 1.0 - ((1.0 - saturation) * 2.0);
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if (sat < 0.3) sat = 0.3;
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// float wscale = 1.732;
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// an overexposure filter, the log() seems to be pretty expensive though
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// if (color.x > 0.8) color.x = 0.8 + 0.8* log(color.x/0.8);
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// if (color.y > 0.8) color.y = 0.8 + 0.8* log(color.y/0.8);
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// if (color.z > 0.8) color.z = 0.8 + 0.8* log(color.z/0.8);
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// a different exposure filter
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//color.x = 1.0 - exp(-1.3 * color.x);
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//color.y = 1.0 - exp(-1.3 * color.y);
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//color.z = 1.0 - exp(-1.3 * color.z);
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if (color.r > 0.58) color.r = 1.0 - exp(-1.5 * color.r);
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if (color.g > 0.58) color.g = 1.0 - exp(-1.5 * color.g);
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if (color.b > 0.58) color.b = 1.0 - exp(-1.5 * color.b);
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// reduce the whiteout near the horizon generated by the single scattering approximation
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//if (ct > cthorizon) color = mix(color, black ,smoothstep(0.2+cthorizon, -0.2+cthorizon, ct));
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//else color = mix (color, black, smoothstep(0.2+cthorizon,-0.2+cthorizon, cthorizon));
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// fog computations for a ground haze layer, extending from zero to lAltitude
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float transmission;
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float vAltitude;
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float delta_zv;
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float costheta = ct;
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float vis = min(visibility, avisibility);
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// hack - in an effect volume the visibility only may be reduced, so we take care here
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//if (avisibility < visibility){vis = avisibility;}
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if (delta_z > 0.0) // we're inside the layer
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{
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if (costheta>0.0 + ctterrain) // looking up, view ray intersecting upper layer edge
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{
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transmission = exp(-min((delta_z/max(costheta,0.1)),25000.0)/vis);
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//transmission = 1.0;
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vAltitude = min(vis * costheta, delta_z);
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delta_zv = delta_z - vAltitude;
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}
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else // looking down, view range intersecting terrain (which may not be drawn)
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{
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transmission = exp(alt/vis/costheta);
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vAltitude = min(-vis * costheta, alt);
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delta_zv = delta_z + vAltitude;
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}
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}
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else // we see the layer from above
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{
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if (costheta < 0.0 + cthorizon)
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{
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transmission = exp(-min(lAltitude/abs(costheta),25000.0)/vis);
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transmission = transmission * exp(-alt/avisibility/abs(costheta));
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transmission = 1.0 - (1.0 - transmission) * smoothstep(0+cthorizon, -0.02+cthorizon, costheta);
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vAltitude = min(lAltitude, -vis * costheta);
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delta_zv = vAltitude;
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}
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else
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{
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transmission = 1.0;
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delta_zv = 0.0;
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}
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}
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// combined intensity reduction by cloud shading and fog self-shading, corrected for Weber-Fechner perception law
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//float scattering = ground_scattering + (1.0 - ground_scattering) * smoothstep(avisibility, 1.5 * avisibility, -alt/costheta);
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float eqColorFactor = 1.0 - 0.1 * delta_zv/vis - (1.0 - min(scattering,cloud_self_shading));
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// there's always residual intensity, we should never be driven to zero
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if (eqColorFactor < 0.2) eqColorFactor = 0.2;
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// postprocessing of haze color
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vec3 hColor = hazeColor;
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// high altitude desaturation
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float intensity = length(hColor);
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hColor = intensity * normalize (mix(hColor, intensity * vec3 (1.0,1.0,1.0), 0.7* smoothstep(5000.0, 50000.0, alt)));
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// blue hue
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hColor.x = 0.83 * hColor.x;
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hColor.y = 0.9 * hColor.y;
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// further blueshift when in shadow, either cloud shadow, or self-shadow or Earth shadow, dependent on indirect
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// light
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float fade_out = max(0.65 - 0.3 *overcast, 0.45);
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intensity = length(hColor);
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vec3 oColor = hColor;
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oColor = intensity * normalize(mix(oColor, shadedFogColor, (smoothstep(0.1,1.0,ovc))));
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color = ovc * mix(color, oColor * earthShade ,smoothstep(-0.1+ctterrain, 0.0+ctterrain, ct)) + (1-ovc) * color;
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hColor = intensity * normalize(mix(hColor, 1.5 * shadedFogColor, 1.0 -smoothstep(0.25, fade_out,earthShade) ));
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hColor = intensity * normalize(mix(hColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,eqColorFactor))));
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//hColor = intensity * normalize(mix(hColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,cloud_self_shading)) ));
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hColor = hColor * earthShade;
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// accounting for overcast and saturation
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color = sat * color + (1.0 - sat) * mix(color, black, smoothstep(0.4+cthorizon,0.2+cthorizon,ct));
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// the terrain below the horizon gets drawn in one optical thickness
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vec3 terrainHazeColor = eqColorFactor * hColor;
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color = mix(color, terrainHazeColor ,smoothstep(0.01 + ctterrain, 0.0+ctterrain, ct));
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// mix fog the skydome with the right amount of haze
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color = transmission * color + (1.0-transmission) * eqColorFactor * hColor;
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vec3 black = vec3(0.0,0.0,0.0);
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float ovc = overcast;
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float sat = 1.0 - ((1.0 - saturation) * 2.0);
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if (sat < 0.3) sat = 0.3;
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// float wscale = 1.732;
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// an overexposure filter, the log() seems to be pretty expensive though
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// if (color.x > 0.8) color.x = 0.8 + 0.8* log(color.x/0.8);
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// if (color.y > 0.8) color.y = 0.8 + 0.8* log(color.y/0.8);
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// if (color.z > 0.8) color.z = 0.8 + 0.8* log(color.z/0.8);
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// a different exposure filter
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//color.x = 1.0 - exp(-1.3 * color.x);
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//color.y = 1.0 - exp(-1.3 * color.y);
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//color.z = 1.0 - exp(-1.3 * color.z);
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if (color.r > 0.58) color.r = 1.0 - exp(-1.5 * color.r);
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if (color.g > 0.58) color.g = 1.0 - exp(-1.5 * color.g);
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if (color.b > 0.58) color.b = 1.0 - exp(-1.5 * color.b);
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// reduce the whiteout near the horizon generated by the single scattering approximation
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//if (ct > cthorizon) color = mix(color, black ,smoothstep(0.2+cthorizon, -0.2+cthorizon, ct));
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//else color = mix (color, black, smoothstep(0.2+cthorizon,-0.2+cthorizon, cthorizon));
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// fog computations for a ground haze layer, extending from zero to lAltitude
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float transmission;
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float vAltitude;
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float delta_zv;
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float costheta = ct;
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float vis = min(visibility, avisibility);
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// hack - in an effect volume the visibility only may be reduced, so we take care here
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//if (avisibility < visibility){vis = avisibility;}
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if (delta_z > 0.0) // we're inside the layer
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{
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if (costheta>0.0 + ctterrain) // looking up, view ray intersecting upper layer edge
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{
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transmission = exp(-min((delta_z/max(costheta,0.1)),25000.0)/vis);
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//transmission = 1.0;
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vAltitude = min(vis * costheta, delta_z);
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delta_zv = delta_z - vAltitude;
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}
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else // looking down, view range intersecting terrain (which may not be drawn)
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{
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transmission = exp(alt/vis/costheta);
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vAltitude = min(-vis * costheta, alt);
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delta_zv = delta_z + vAltitude;
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}
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}
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else // we see the layer from above
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{
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if (costheta < 0.0 + cthorizon)
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{
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transmission = exp(-min(lAltitude/abs(costheta),25000.0)/vis);
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transmission = transmission * exp(-alt/avisibility/abs(costheta));
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transmission = 1.0 - (1.0 - transmission) * smoothstep(0+cthorizon, -0.02+cthorizon, costheta);
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vAltitude = min(lAltitude, -vis * costheta);
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delta_zv = vAltitude;
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}
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else
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{
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transmission = 1.0;
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delta_zv = 0.0;
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}
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}
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// combined intensity reduction by cloud shading and fog self-shading, corrected for Weber-Fechner perception law
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//float scattering = ground_scattering + (1.0 - ground_scattering) * smoothstep(avisibility, 1.5 * avisibility, -alt/costheta);
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float eqColorFactor = 1.0 - 0.1 * delta_zv/vis - (1.0 - min(scattering,cloud_self_shading));
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// there's always residual intensity, we should never be driven to zero
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||||
if (eqColorFactor < 0.2) eqColorFactor = 0.2;
|
||||
|
||||
|
||||
// postprocessing of haze color
|
||||
vec3 hColor = hazeColor;
|
||||
|
||||
|
||||
// high altitude desaturation
|
||||
float intensity = length(hColor);
|
||||
hColor = intensity * normalize (mix(hColor, intensity * vec3 (1.0,1.0,1.0), 0.7* smoothstep(5000.0, 50000.0, alt)));
|
||||
|
||||
// blue hue
|
||||
hColor.x = 0.83 * hColor.x;
|
||||
hColor.y = 0.9 * hColor.y;
|
||||
|
||||
|
||||
|
||||
// further blueshift when in shadow, either cloud shadow, or self-shadow or Earth shadow, dependent on indirect
|
||||
// light
|
||||
|
||||
float fade_out = max(0.65 - 0.3 *overcast, 0.45);
|
||||
intensity = length(hColor);
|
||||
vec3 oColor = hColor;
|
||||
oColor = intensity * normalize(mix(oColor, shadedFogColor, (smoothstep(0.1,1.0,ovc))));
|
||||
color = ovc * mix(color, oColor * earthShade ,smoothstep(-0.1+ctterrain, 0.0+ctterrain, ct)) + (1-ovc) * color;
|
||||
hColor = intensity * normalize(mix(hColor, 1.5 * shadedFogColor, 1.0 -smoothstep(0.25, fade_out,earthShade) ));
|
||||
hColor = intensity * normalize(mix(hColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,eqColorFactor))));
|
||||
//hColor = intensity * normalize(mix(hColor, shadedFogColor, (1.0 - smoothstep(0.5,0.9,cloud_self_shading)) ));
|
||||
hColor = hColor * earthShade;
|
||||
|
||||
// accounting for overcast and saturation
|
||||
|
||||
|
||||
|
||||
color = sat * color + (1.0 - sat) * mix(color, black, smoothstep(0.4+cthorizon,0.2+cthorizon,ct));
|
||||
|
||||
|
||||
// the terrain below the horizon gets drawn in one optical thickness
|
||||
vec3 terrainHazeColor = eqColorFactor * hColor;
|
||||
|
||||
// determine a visibility-dependent angle for how smoothly the haze blends over the skydome
|
||||
|
||||
float hazeBlendAngle = max(0.01,1000.0/avisibility + 0.3 * (1.0 - smoothstep(5000.0, 30000.0, avisibility)));
|
||||
float altFactor = smoothstep(-300.0, 0.0, delta_z);
|
||||
float altFactor2 = 0.2 + 0.8 * smoothstep(-3000.0, 0.0, delta_z);
|
||||
hazeBlendAngle = hazeBlendAngle + 0.1 * altFactor;
|
||||
hazeBlendAngle = hazeBlendAngle + (1.0-horizon_roughness) * altFactor2 * 0.1 * Noise2D(vec2(0.0,cphi), 0.3);
|
||||
|
||||
|
||||
color = mix(color, terrainHazeColor ,smoothstep(hazeBlendAngle + ctterrain, 0.0+ctterrain, ct));
|
||||
|
||||
|
||||
// mix fog the skydome with the right amount of haze
|
||||
|
||||
color = transmission * color + (1.0-transmission) * eqColorFactor * hColor;
|
||||
|
||||
|
||||
gl_FragColor = vec4(color, 1.0);
|
||||
gl_FragDepth = 0.1;
|
||||
gl_FragDepth = 0.1;
|
||||
|
||||
}
|
||||
|
||||
|
|
|
|||
|
|
@ -6,29 +6,29 @@
|
|||
|
||||
|
||||
uniform mat4 osg_ViewMatrix;
|
||||
uniform mat4 osg_ViewMatrixInverse;
|
||||
uniform float hazeLayerAltitude;
|
||||
uniform float terminator;
|
||||
uniform float avisibility;
|
||||
uniform mat4 osg_ViewMatrixInverse;
|
||||
uniform float hazeLayerAltitude;
|
||||
uniform float terminator;
|
||||
uniform float avisibility;
|
||||
uniform float visibility;
|
||||
uniform float terrain_alt;
|
||||
uniform float terrain_alt;
|
||||
|
||||
varying vec3 rayleigh;
|
||||
varying vec3 mie;
|
||||
varying vec3 eye;
|
||||
varying vec3 hazeColor;
|
||||
varying float ct;
|
||||
//varying float cosphi;
|
||||
varying float delta_z;
|
||||
varying float alt;
|
||||
varying float earthShade;
|
||||
varying vec3 eye;
|
||||
varying vec3 hazeColor;
|
||||
varying float ct;
|
||||
varying float cphi;
|
||||
varying float delta_z;
|
||||
varying float alt;
|
||||
varying float earthShade;
|
||||
|
||||
// Dome parameters from FG and screen
|
||||
const float domeSize = 80000.0;
|
||||
const float realDomeSize = 100000.0;
|
||||
const float groundRadius = 0.984503332 * domeSize;
|
||||
const float altitudeScale = domeSize - groundRadius;
|
||||
const float EarthRadius = 5800000.0;
|
||||
const float EarthRadius = 5800000.0;
|
||||
|
||||
// Dome parameters when calculating scattering
|
||||
// Assuming dome size is 5.0
|
||||
|
|
@ -43,25 +43,25 @@ const float fSamples = float(nSamples);
|
|||
uniform float rK = 0.0003; //0.00015;
|
||||
uniform float mK = 0.003; //0.0025;
|
||||
uniform float density = 0.5; //1.0
|
||||
//vec3 rayleighK = rK * vec3(5.602, 7.222, 19.644);
|
||||
//vec3 rayleighK = rK * vec3(5.602, 7.222, 19.644);
|
||||
vec3 rayleighK = rK * vec3(4.5, 8.62, 17.3);
|
||||
vec3 mieK = vec3(mK);
|
||||
vec3 sunIntensity = 10.0*vec3(120.0, 125.0, 130.0);
|
||||
|
||||
// light_func is a generalized logistic function fit to the light intensity as a function
|
||||
// of scaled terminator position obtained from Flightgear core
|
||||
|
||||
float light_func (in float x, in float a, in float b, in float c, in float d, in float e)
|
||||
{
|
||||
x = x - 0.5;
|
||||
|
||||
// use the asymptotics to shorten computations
|
||||
if (x > 30.0) {return e;}
|
||||
if (x < -15.0) {return 0.0;}
|
||||
|
||||
return e / pow((1.0 + a * exp(-b * (x-c)) ),(1.0/d));
|
||||
}
|
||||
|
||||
|
||||
// light_func is a generalized logistic function fit to the light intensity as a function
|
||||
// of scaled terminator position obtained from Flightgear core
|
||||
|
||||
float light_func (in float x, in float a, in float b, in float c, in float d, in float e)
|
||||
{
|
||||
x = x - 0.5;
|
||||
|
||||
// use the asymptotics to shorten computations
|
||||
if (x > 30.0) {return e;}
|
||||
if (x < -15.0) {return 0.0;}
|
||||
|
||||
return e / pow((1.0 + a * exp(-b * (x-c)) ),(1.0/d));
|
||||
}
|
||||
|
||||
|
||||
// Find intersections of ray to skydome
|
||||
// ray must be normalized
|
||||
|
|
@ -76,8 +76,8 @@ float intersection (in float cheight, in vec3 ray, in float rad2)
|
|||
|
||||
// Return the scale function at height = 0 for different thetas
|
||||
float outscatterscale(in float costheta)
|
||||
{
|
||||
|
||||
{
|
||||
|
||||
|
||||
float x = 1.0 - costheta;
|
||||
|
||||
|
|
@ -115,11 +115,11 @@ void main()
|
|||
// Make it so that 0.0 is ground level and 1.0 is 100km (space) level
|
||||
float altitude = distance(groundPoint, vec4(0.0, 0.0, 0.0, 1.0));
|
||||
float scaledAltitude = altitude / realDomeSize;
|
||||
|
||||
// the local horizon angle
|
||||
float radiusEye = EarthRadius + altitude;
|
||||
float ctterrain = -sqrt(radiusEye * radiusEye - EarthRadius * EarthRadius)/radiusEye;
|
||||
|
||||
|
||||
// the local horizon angle
|
||||
float radiusEye = EarthRadius + altitude;
|
||||
float ctterrain = -sqrt(radiusEye * radiusEye - EarthRadius * EarthRadius)/radiusEye;
|
||||
|
||||
|
||||
// Camera's position, z is up!
|
||||
float cameraRealAltitude = groundLevel + heightScale*scaledAltitude;
|
||||
|
|
@ -133,7 +133,7 @@ void main()
|
|||
// We are in space, calculate correct positiondelta!
|
||||
relativePosition -= space * normalize(relativePosition);
|
||||
}
|
||||
|
||||
|
||||
|
||||
vec3 positionDelta = relativePosition / fSamples;
|
||||
float deltaLength = length(positionDelta); // Should multiply by something?
|
||||
|
|
@ -147,20 +147,20 @@ void main()
|
|||
// If sample is above camera, reverse ray direction
|
||||
if(positionDelta.z < 0.0) cameraCosTheta = -positionDelta.z / deltaLength;
|
||||
else cameraCosTheta = positionDelta.z / deltaLength;
|
||||
|
||||
|
||||
float cameraCosTheta1 = -positionDelta.z / deltaLength;
|
||||
|
||||
|
||||
|
||||
float cameraCosTheta1 = -positionDelta.z / deltaLength;
|
||||
|
||||
|
||||
// Total attenuation from camera to skydome
|
||||
float totalCameraScatter = outscatter(cameraCosTheta, scaledAltitude);
|
||||
|
||||
|
||||
// Do numerical integration of scattering function from skydome to camera
|
||||
vec3 color = vec3(0.0);
|
||||
|
||||
// no scattering integrations where terrain is later drawn
|
||||
if (cameraCosTheta1 > (ctterrain-0.05))
|
||||
vec3 color = vec3(0.0);
|
||||
|
||||
// no scattering integrations where terrain is later drawn
|
||||
if (cameraCosTheta1 > (ctterrain-0.05))
|
||||
{
|
||||
for(int i = 0; i < nSamples; i++)
|
||||
{
|
||||
|
|
@ -179,7 +179,7 @@ void main()
|
|||
// Again, reverse the direction if vertex is over the camera
|
||||
float cameraScatter;
|
||||
if(relativePosition.z < 0.0) { // Vertex is over the camera
|
||||
cameraCosTheta = -dot(normalize(positionDelta), normalize(sample));
|
||||
cameraCosTheta = -dot(normalize(positionDelta), normalize(sample));
|
||||
|
||||
cameraScatter = totalCameraScatter - outscatter(cameraCosTheta, sampleAltitude);
|
||||
} else { // Vertex is below camera
|
||||
|
|
@ -196,13 +196,13 @@ void main()
|
|||
sample += positionDelta;
|
||||
}
|
||||
}
|
||||
color *= sunIntensity;
|
||||
color *= sunIntensity;
|
||||
ct = cameraCosTheta1;
|
||||
rayleigh = rayleighK * color;
|
||||
mie = mieK * color;
|
||||
eye = gl_NormalMatrix * positionDelta;
|
||||
|
||||
|
||||
|
||||
|
||||
// We need to move the camera so that the dome appears to be centered around earth
|
||||
// to make the dome render correctly!
|
||||
float moveDown = -altitude; // Center dome on camera
|
||||
|
|
@ -210,82 +210,65 @@ void main()
|
|||
moveDown += scaledAltitude * altitudeScale; // And move correctly according to altitude
|
||||
|
||||
// Vertex transformed correctly so that at 100km we are at space border
|
||||
vec4 finalVertex = realVertex - vec4(0.0, 0.0, 1.0, 0.0) * moveDown;
|
||||
|
||||
// prepare some stuff for a ground haze layer
|
||||
|
||||
delta_z = hazeLayerAltitude - altitude;
|
||||
alt = altitude;
|
||||
|
||||
|
||||
// establish coordinates relative to sun position
|
||||
vec4 ep = gl_ModelViewMatrixInverse * vec4(0.0,0.0,0.0,1.0);
|
||||
vec3 lightFull = (gl_ModelViewMatrixInverse * gl_LightSource[0].position).xyz;
|
||||
vec3 lightHorizon = normalize(vec3(lightFull.x,lightFull.y, 0.0) );
|
||||
|
||||
|
||||
vec3 relVector = normalize(finalVertex.xyz - ep.xyz);
|
||||
|
||||
// and compute the twilight shading
|
||||
|
||||
|
||||
// yprime is the coordinate from/towards terminator
|
||||
float yprime;
|
||||
|
||||
if (alt > hazeLayerAltitude) // we're looking from above and can see far
|
||||
{
|
||||
if (ct < 0.0)
|
||||
{
|
||||
yprime = -dot(relVector,lightHorizon) * altitude/-ct;//(ct-0.001);
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * hazeLayerAltitude);
|
||||
}
|
||||
else // the only haze we see looking up is overcast, assume its altitude
|
||||
{
|
||||
yprime = -dot(relVector,lightHorizon) * avisibility;
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * 10000.0);
|
||||
}
|
||||
}
|
||||
else
|
||||
{yprime = -dot(relVector,lightHorizon) * avisibility;
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * hazeLayerAltitude);
|
||||
}
|
||||
|
||||
if (terminator > 1000000.0){yprime = -sqrt(2.0 * EarthRadius * hazeLayerAltitude);}
|
||||
|
||||
//float edgeAlt = max(hazeLayerAltitude - (alt-terrain_alt)/avisibility * visibility, terrain_alt);
|
||||
|
||||
//yprime = yprime -sqrt(2.0 * EarthRadius * edgeAlt);
|
||||
|
||||
float terminator_width = 200000.0;
|
||||
earthShade = 0.9 * smoothstep((terminator_width+ terminator), (-terminator_width + terminator), yprime) + 0.1;
|
||||
|
||||
|
||||
//hazeColor = vec3 (gl_LightSource[0].diffuse.x, gl_LightSource[0].diffuse.y, gl_LightSource[0].diffuse.z);
|
||||
|
||||
//hazeColor.x = hazeColor.x * 0.83;
|
||||
//hazeColor.y = hazeColor.y * 0.9;
|
||||
|
||||
float lightArg = (terminator-yprime)/100000.0;
|
||||
vec4 light_diffuse;
|
||||
light_diffuse.b = light_func(lightArg, 1.330e-05, 0.264, 2.527, 1.08e-05, 1.0);
|
||||
light_diffuse.g = light_func(lightArg, 3.931e-06, 0.264, 3.827, 7.93e-06, 1.0);
|
||||
light_diffuse.r = light_func(lightArg, 8.305e-06, 0.161, 3.827, 3.04e-05, 1.0);
|
||||
light_diffuse.a = 0.0;
|
||||
hazeColor = light_diffuse.xyz;
|
||||
|
||||
float intensity = length(hazeColor.xyz);
|
||||
float mie_magnitude = 0.5 * smoothstep(350000.0, 150000.0, terminator -sqrt(2.0 * EarthRadius * terrain_alt));
|
||||
float mie_angle = (0.5 * dot(normalize(relVector), normalize(lightFull)) ) + 0.5;
|
||||
hazeColor = intensity * ((1.0 - mie_magnitude) + mie_magnitude * mie_angle) * normalize(mix(hazeColor, vec3 (0.5, 0.58, 0.65), mie_magnitude * (0.5 - 0.5 * mie_angle)) );
|
||||
|
||||
|
||||
// high altitude desaturation - would be best here this causes a box-like bug for some reason
|
||||
// so it moved to the fragment shader where it has no issues
|
||||
|
||||
//float intensity = length(hazeColor.xyz);
|
||||
//hazeColor = intensity * normalize (mix(hazeColor, intensity * vec3 (1.0,1.0,1.0), 0.8* smoothstep(5000.0, 50000.0, alt)));
|
||||
|
||||
|
||||
vec4 finalVertex = realVertex - vec4(0.0, 0.0, 1.0, 0.0) * moveDown;
|
||||
|
||||
// prepare some stuff for a ground haze layer
|
||||
|
||||
delta_z = hazeLayerAltitude - altitude;
|
||||
alt = altitude;
|
||||
|
||||
|
||||
// establish coordinates relative to sun position
|
||||
vec4 ep = gl_ModelViewMatrixInverse * vec4(0.0,0.0,0.0,1.0);
|
||||
vec3 lightFull = (gl_ModelViewMatrixInverse * gl_LightSource[0].position).xyz;
|
||||
vec3 lightHorizon = normalize(vec3(lightFull.x,lightFull.y, 0.0) );
|
||||
|
||||
|
||||
vec3 relVector = normalize(finalVertex.xyz - ep.xyz);
|
||||
|
||||
// and compute the twilight shading
|
||||
|
||||
|
||||
// yprime is the coordinate from/towards terminator
|
||||
float yprime;
|
||||
|
||||
if (alt > hazeLayerAltitude) // we're looking from above and can see far
|
||||
{
|
||||
if (ct < 0.0)
|
||||
{
|
||||
yprime = -dot(relVector,lightHorizon) * altitude/-ct;//(ct-0.001);
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * hazeLayerAltitude);
|
||||
}
|
||||
else // the only haze we see looking up is overcast, assume its altitude
|
||||
{
|
||||
yprime = -dot(relVector,lightHorizon) * avisibility;
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * 10000.0);
|
||||
}
|
||||
}
|
||||
else
|
||||
{yprime = -dot(relVector,lightHorizon) * avisibility;
|
||||
yprime = yprime -sqrt(2.0 * EarthRadius * hazeLayerAltitude);
|
||||
}
|
||||
|
||||
if (terminator > 1000000.0){yprime = -sqrt(2.0 * EarthRadius * hazeLayerAltitude);}
|
||||
|
||||
float terminator_width = 200000.0;
|
||||
earthShade = 0.9 * smoothstep((terminator_width+ terminator), (-terminator_width + terminator), yprime) + 0.1;
|
||||
|
||||
float lightArg = (terminator-yprime)/100000.0;
|
||||
vec4 light_diffuse;
|
||||
light_diffuse.b = light_func(lightArg, 1.330e-05, 0.264, 2.527, 1.08e-05, 1.0);
|
||||
light_diffuse.g = light_func(lightArg, 3.931e-06, 0.264, 3.827, 7.93e-06, 1.0);
|
||||
light_diffuse.r = light_func(lightArg, 8.305e-06, 0.161, 3.827, 3.04e-05, 1.0);
|
||||
light_diffuse.a = 0.0;
|
||||
hazeColor = light_diffuse.xyz;
|
||||
|
||||
float intensity = length(hazeColor.xyz);
|
||||
float mie_magnitude = 0.5 * smoothstep(350000.0, 150000.0, terminator -sqrt(2.0 * EarthRadius * terrain_alt));
|
||||
cphi = dot(normalize(relVector), normalize(lightHorizon));
|
||||
float mie_angle = (0.5 * dot(normalize(relVector), normalize(lightFull)) ) + 0.5;
|
||||
hazeColor = intensity * ((1.0 - mie_magnitude) + mie_magnitude * mie_angle) * normalize(mix(hazeColor, vec3 (0.5, 0.58, 0.65), mie_magnitude * (0.5 - 0.5 * mie_angle)) );
|
||||
|
||||
|
||||
// Transform
|
||||
gl_Position = gl_ModelViewProjectionMatrix * finalVertex;
|
||||
|
|
|
|||
Loading…
Reference in a new issue