695 lines
22 KiB
C++
695 lines
22 KiB
C++
// -*-C++-*-
|
|
|
|
// written by Thorsten Renk, Oct 2011, based on default.frag
|
|
// Ambient term comes in gl_Color.rgb.
|
|
varying vec4 diffuse_term;
|
|
varying vec3 normal;
|
|
varying vec3 relPos;
|
|
varying vec2 rawPos;
|
|
varying vec3 worldPos;
|
|
varying vec3 ecViewdir;
|
|
varying vec2 grad_dir;
|
|
|
|
|
|
uniform sampler2D texture;
|
|
uniform sampler2D detail_texture;
|
|
uniform sampler2D mix_texture;
|
|
uniform sampler2D grain_texture;
|
|
uniform sampler2D dot_texture;
|
|
uniform sampler2D gradient_texture;
|
|
|
|
|
|
|
|
//varying float yprime_alt;
|
|
//varying float mie_angle;
|
|
varying float steepness;
|
|
|
|
|
|
|
|
uniform float visibility;
|
|
uniform float avisibility;
|
|
uniform float scattering;
|
|
uniform float terminator;
|
|
uniform float terrain_alt;
|
|
uniform float hazeLayerAltitude;
|
|
uniform float overcast;
|
|
uniform float eye_alt;
|
|
uniform float snowlevel;
|
|
uniform float dust_cover_factor;
|
|
uniform float lichen_cover_factor;
|
|
uniform float wetness;
|
|
uniform float fogstructure;
|
|
uniform float snow_thickness_factor;
|
|
uniform float cloud_self_shading;
|
|
uniform float season;
|
|
uniform float air_pollution;
|
|
uniform float grain_strength;
|
|
uniform float intrinsic_wetness;
|
|
uniform float transition_model;
|
|
uniform float hires_overlay_bias;
|
|
uniform float dot_density;
|
|
uniform float dot_size;
|
|
uniform float dust_resistance;
|
|
uniform float WindE;
|
|
uniform float WindN;
|
|
uniform float landing_light1_offset;
|
|
uniform float landing_light2_offset;
|
|
uniform float osg_SimulationTime;
|
|
|
|
uniform int quality_level;
|
|
uniform int tquality_level;
|
|
uniform int wind_effects;
|
|
uniform int cloud_shadow_flag;
|
|
uniform int rock_strata;
|
|
uniform int use_searchlight;
|
|
uniform int use_landing_light;
|
|
uniform int use_alt_landing_light;
|
|
|
|
const float EarthRadius = 5800000.0;
|
|
const float terminator_width = 200000.0;
|
|
|
|
//float alt;
|
|
float eShade;
|
|
float yprime_alt;
|
|
float mie_angle;
|
|
|
|
float shadow_func (in float x, in float y, in float noise, in float dist);
|
|
float DotNoise2D(in vec2 coord, in float wavelength, in float fractionalMaxDotSize, in float dot_density);
|
|
float Noise2D(in vec2 coord, in float wavelength);
|
|
float Noise3D(in vec3 coord, in float wavelength);
|
|
float SlopeLines2D(in vec2 coord, in vec2 gradDir, in float wavelength, in float steepness);
|
|
float Strata3D(in vec3 coord, in float wavelength, in float variation);
|
|
float fog_func (in float targ, in float alt);
|
|
float rayleigh_in_func(in float dist, in float air_pollution, in float avisibility, in float eye_alt, in float vertex_alt);
|
|
float alt_factor(in float eye_alt, in float vertex_alt);
|
|
vec3 rayleigh_out_shift(in vec3 color, in float outscatter);
|
|
vec3 searchlight(in float dist);
|
|
vec3 landing_light(in float dist, in float offset);
|
|
|
|
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));
|
|
}
|
|
|
|
|
|
// a fade function for procedural scales which are smaller than a pixel
|
|
|
|
float detail_fade (in float scale, in float angle, in float dist)
|
|
{
|
|
float fade_dist = 2000.0 * scale * angle/max(pow(steepness,4.0), 0.1);
|
|
|
|
return 1.0 - smoothstep(0.5 * fade_dist, fade_dist, dist);
|
|
}
|
|
|
|
|
|
|
|
void main()
|
|
{
|
|
|
|
float alt;
|
|
|
|
yprime_alt = diffuse_term.a;
|
|
//diffuse_term.a = 1.0;
|
|
mie_angle = gl_Color.a;
|
|
float effective_scattering = min(scattering, cloud_self_shading);
|
|
|
|
// distance to fragment
|
|
float dist = length(relPos);
|
|
// angle of view vector with horizon
|
|
float ct = dot(vec3(0.0, 0.0, 1.0), relPos)/dist;
|
|
// float altitude of fragment above sea level
|
|
float msl_altitude = (relPos.z + eye_alt);
|
|
|
|
|
|
vec3 shadedFogColor = vec3(0.65, 0.67, 0.78);
|
|
// this is taken from default.frag
|
|
vec3 n;
|
|
float NdotL, NdotHV, fogFactor;
|
|
vec4 color = gl_Color;
|
|
color.a = 1.0;
|
|
vec3 lightDir = gl_LightSource[0].position.xyz;
|
|
vec3 halfVector = normalize(normalize(lightDir) + normalize(ecViewdir));
|
|
vec4 texel;
|
|
vec4 snow_texel;
|
|
vec4 detail_texel;
|
|
vec4 mix_texel;
|
|
vec4 grain_texel;
|
|
vec4 dot_texel;
|
|
vec4 gradient_texel;
|
|
vec4 foam_texel;
|
|
vec4 fragColor;
|
|
vec4 specular = vec4(0.0);
|
|
float intensity;
|
|
|
|
|
|
|
|
// Wind motion of the overlay noise simulating movement of vegetation and loose debris
|
|
|
|
vec2 windPos;
|
|
|
|
if (wind_effects > 1)
|
|
{
|
|
float windSpeed = length(vec2 (WindE,WindN)) /3.0480;
|
|
// interfering sine wave wind pattern
|
|
float sineTerm = sin(0.35 * windSpeed * osg_SimulationTime + 0.05 * (rawPos.x + rawPos.y));
|
|
sineTerm = sineTerm + sin(0.3 * windSpeed * osg_SimulationTime + 0.04 * (rawPos.x + rawPos.y));
|
|
sineTerm = sineTerm + sin(0.22 * windSpeed * osg_SimulationTime + 0.05 * (rawPos.x + rawPos.y));
|
|
sineTerm = sineTerm/3.0;
|
|
// non-linear amplification to simulate gusts
|
|
sineTerm = sineTerm * sineTerm;//smoothstep(0.2, 1.0, sineTerm);
|
|
|
|
// wind starts moving dust and leaves at around 8 m/s
|
|
float timeArg = 0.01 * osg_SimulationTime * windSpeed * smoothstep(8.0, 15.0, windSpeed);
|
|
timeArg = timeArg + 0.02 * sineTerm;
|
|
|
|
windPos = vec2 (rawPos.x + WindN * timeArg, rawPos.y + WindE * timeArg);
|
|
}
|
|
else
|
|
{
|
|
windPos = rawPos.xy;
|
|
}
|
|
|
|
|
|
// get noise at different wavelengths
|
|
|
|
// used: 5m, 5m gradient, 10m, 10m gradient: heightmap of the closeup terrain, 10m also snow
|
|
// 50m: detail texel
|
|
// 250m: detail texel
|
|
// 500m: distortion and overlay
|
|
// 1500m: overlay, detail, dust, fog
|
|
// 2000m: overlay, detail, snow, fog
|
|
|
|
// Perlin noise
|
|
|
|
float noise_10m = Noise2D(rawPos.xy, 10.0);
|
|
float noise_5m = Noise2D(rawPos.xy ,5.0);
|
|
float noise_2m = Noise2D(rawPos.xy ,2.0);
|
|
float noise_1m = Noise2D(rawPos.xy ,1.0);
|
|
float noise_01m = Noise2D(windPos.xy, 0.1);
|
|
|
|
float noisegrad_10m;
|
|
float noisegrad_5m;
|
|
float noisegrad_2m;
|
|
float noisegrad_1m;
|
|
|
|
|
|
|
|
float noise_25m = Noise2D(rawPos.xy, 25.0);
|
|
float noise_50m = Noise2D(rawPos.xy, 50.0);
|
|
|
|
|
|
float noise_250m = Noise3D(worldPos.xyz,250.0);
|
|
float noise_500m = Noise3D(worldPos.xyz, 500.0);
|
|
float noise_1500m = Noise3D(worldPos.xyz, 1500.0);
|
|
float noise_2000m = Noise3D(worldPos.xyz, 2000.0);
|
|
|
|
// dot noise
|
|
|
|
float dotnoise_2m = DotNoise2D(rawPos.xy, 2.0 * dot_size,0.5, dot_density);
|
|
float dotnoise_10m = DotNoise2D(rawPos.xy, 10.0 * dot_size, 0.5, dot_density);
|
|
float dotnoise_15m = DotNoise2D(rawPos.xy, 15.0 * dot_size, 0.33, dot_density);
|
|
|
|
float dotnoisegrad_10m;
|
|
|
|
|
|
// slope noise
|
|
|
|
float slopenoise_50m = SlopeLines2D(rawPos, grad_dir, 50.0, steepness);
|
|
float slopenoise_100m = SlopeLines2D(rawPos, grad_dir, 100.0, steepness);
|
|
|
|
float snownoise_25m = mix(noise_25m, slopenoise_50m, clamp(3.0*(1.0-steepness),0.0,1.0));
|
|
float snownoise_50m = mix(noise_50m, slopenoise_100m, clamp(3.0*(1.0-steepness),0.0,1.0));
|
|
|
|
// get the texels
|
|
|
|
|
|
|
|
float distortion_factor = 1.0;
|
|
vec2 stprime;
|
|
int flag = 1;
|
|
int mix_flag = 1;
|
|
float noise_term;
|
|
float snow_alpha;
|
|
|
|
texel = texture2D(texture, gl_TexCoord[0].st);
|
|
float local_autumn_factor = texel.a;
|
|
grain_texel = texture2D(grain_texture, gl_TexCoord[0].st * 25.0);
|
|
gradient_texel = texture2D(gradient_texture, gl_TexCoord[0].st * 4.0);
|
|
|
|
stprime = gl_TexCoord[0].st * 80.0;
|
|
stprime = stprime + normalize(relPos).xy * 0.01 * (dotnoise_10m + dotnoise_15m);
|
|
dot_texel = texture2D(dot_texture, vec2 (stprime.y, stprime.x) );
|
|
|
|
// we need to fade procedural structures when they get smaller than a single pixel, for this we need
|
|
// to know under what angle we see the surface
|
|
|
|
float view_angle = abs(dot(normalize(normal), normalize(ecViewdir)));
|
|
float sfactor = sqrt(2.0 * (1.0-steepness)/0.03) + abs(ct)/0.15;
|
|
|
|
// the snow texel is generated procedurally
|
|
if (msl_altitude +500.0 > snowlevel)
|
|
{
|
|
snow_texel = vec4 (0.95, 0.95, 0.95, 1.0) * (0.9 + 0.1* noise_500m + 0.1* (1.0 - noise_10m) );
|
|
snow_texel.r = snow_texel.r * (0.9 + 0.05 * (noise_10m + noise_5m));
|
|
snow_texel.g = snow_texel.g * (0.9 + 0.05 * (noise_10m + noise_5m));
|
|
snow_texel.a = 1.0;
|
|
noise_term = 0.1 * (noise_500m-0.5) ;
|
|
noise_term = noise_term + 0.2 * (snownoise_50m -0.5) * detail_fade(50.0, view_angle, 0.5*dist) ;
|
|
noise_term = noise_term + 0.2 * (snownoise_25m -0.5) * detail_fade(25.0, view_angle, 0.5*dist) ;
|
|
noise_term = noise_term + 0.3 * (noise_10m -0.5) * detail_fade(10.0, view_angle, 0.8*dist) ;
|
|
noise_term = noise_term + 0.3 * (noise_5m - 0.5) * detail_fade(5.0, view_angle, dist);
|
|
noise_term = noise_term + 0.15 * (noise_2m -0.5) * detail_fade(2.0, view_angle, dist);
|
|
noise_term = noise_term + 0.08 * (noise_1m -0.5) * detail_fade(1.0, view_angle, dist);
|
|
snow_texel.a = snow_texel.a * 0.2+0.8* smoothstep(0.2,0.8, 0.3 +noise_term + snow_thickness_factor +0.0001*(msl_altitude -snowlevel) );
|
|
}
|
|
|
|
// the mixture/gradient texture
|
|
mix_texel = texture2D(mix_texture, gl_TexCoord[0].st * 1.3);
|
|
if (mix_texel.a <0.1) {mix_flag = 0;}
|
|
|
|
// the hires overlay texture is loaded with parallax mapping
|
|
|
|
stprime = vec2 (0.86*gl_TexCoord[0].s + 0.5*gl_TexCoord[0].t, 0.5*gl_TexCoord[0].s - 0.86*gl_TexCoord[0].t);
|
|
distortion_factor = 0.97 + 0.06 * noise_500m;
|
|
stprime = stprime * distortion_factor * 15.0;
|
|
stprime = stprime + normalize(relPos).xy * 0.022 * (noise_10m + 0.5 * noise_5m +0.25 * noise_2m - 0.875 );
|
|
|
|
detail_texel = texture2D(detail_texture, stprime);
|
|
if (detail_texel.a <0.1) {flag = 0;}
|
|
|
|
|
|
|
|
// texture preparation according to detail level
|
|
|
|
// mix in hires texture patches
|
|
|
|
float dist_fact;
|
|
float nSum;
|
|
float mix_factor;
|
|
|
|
// first the second texture overlay
|
|
// transition model 0: random patch overlay without any gradient information
|
|
// transition model 1: only gradient-driven transitions, no randomness
|
|
|
|
|
|
if (mix_flag == 1)
|
|
{
|
|
nSum = 0.18 * (2.0 * noise_2000m + 2.0 * noise_1500m + noise_500m);
|
|
nSum = mix(nSum, 0.5, max(0.0, 2.0 * (transition_model - 0.5)));
|
|
nSum = nSum + 0.4 * (1.0 -smoothstep(0.9,0.95, abs(steepness)+ 0.05 * (noise_50m - 0.5))) * min(1.0, 2.0 * transition_model);
|
|
mix_factor = smoothstep(0.5, 0.54, nSum);
|
|
texel = mix(texel, mix_texel, mix_factor);
|
|
local_autumn_factor = texel.a;
|
|
}
|
|
|
|
// then the detail texture overlay
|
|
|
|
mix_factor = 0.0;
|
|
if (dist < 40000.0)
|
|
{
|
|
if (flag == 1)
|
|
{
|
|
dist_fact = 0.1 * smoothstep(15000.0,40000.0, dist) - 0.03 * (1.0 - smoothstep(500.0,5000.0, dist));
|
|
nSum = ((1.0 -noise_2000m) + noise_1500m + 2.0 * noise_250m +noise_50m)/5.0;
|
|
nSum = nSum - 0.08 * (1.0 -smoothstep(0.9,0.95, abs(steepness)));
|
|
mix_factor = smoothstep(0.47, 0.54, nSum +hires_overlay_bias- dist_fact);
|
|
if (mix_factor > 0.8) {mix_factor = 0.8;}
|
|
texel = mix(texel, detail_texel,mix_factor);
|
|
}
|
|
}
|
|
|
|
// rock for very steep gradients
|
|
|
|
if (gradient_texel.a > 0.0)
|
|
{
|
|
texel = mix(texel, gradient_texel, 1.0 - smoothstep(0.75,0.8,abs(steepness)+ 0.00002* msl_altitude + 0.05 * (noise_50m - 0.5)));
|
|
local_autumn_factor = texel.a;
|
|
}
|
|
|
|
|
|
// strata noise
|
|
|
|
float stratnoise_50m;
|
|
float stratnoise_10m;
|
|
|
|
if (rock_strata==1)
|
|
{
|
|
stratnoise_50m = Strata3D(vec3 (rawPos.x, rawPos.y, msl_altitude), 50.0, 0.2);
|
|
stratnoise_10m = Strata3D(vec3 (rawPos.x, rawPos.y, msl_altitude), 10.0, 0.2);
|
|
stratnoise_50m = mix(stratnoise_50m, 1.0, smoothstep(0.8,0.9, steepness));
|
|
stratnoise_10m = mix(stratnoise_10m, 1.0, smoothstep(0.8,0.9, steepness));
|
|
texel *= (0.4 + 0.4 * stratnoise_50m + 0.2 * stratnoise_10m);
|
|
}
|
|
|
|
// the dot vegetation texture overlay
|
|
|
|
texel.rgb = mix(texel.rgb, dot_texel.rgb, dot_texel.a * (dotnoise_10m + dotnoise_15m) * detail_fade(1.0 * (dot_size * (1.0 +0.1*dot_size)), view_angle,dist));
|
|
texel.rgb = mix(texel.rgb, dot_texel.rgb, dot_texel.a * dotnoise_2m * detail_fade(0.1 * dot_size, view_angle,dist));
|
|
|
|
|
|
// then the grain texture overlay
|
|
|
|
texel.rgb = mix(texel.rgb, grain_texel.rgb, grain_strength * grain_texel.a * (1.0 - mix_factor) * (1.0-smoothstep(2000.0,5000.0, dist)));
|
|
|
|
// for really hires, add procedural noise overlay
|
|
texel.rgb = texel.rgb * (1.0 + 0.4 * (noise_01m-0.5) * detail_fade(0.1, view_angle, dist)) ;
|
|
|
|
// autumn colors
|
|
|
|
float autumn_factor = season * 2.0 * (1.0 - local_autumn_factor) ;
|
|
|
|
|
|
texel.r = min(1.0, (1.0 + 2.5 * autumn_factor) * texel.r);
|
|
texel.g = texel.g;
|
|
texel.b = max(0.0, (1.0 - 4.0 * autumn_factor) * texel.b);
|
|
|
|
|
|
if (local_autumn_factor < 1.0)
|
|
{
|
|
intensity = length(texel.rgb) * (1.0 - 0.5 * smoothstep(1.1,2.0,season));
|
|
texel.rgb = intensity * normalize(mix(texel.rgb, vec3(0.23,0.17,0.08), smoothstep(1.1,2.0, season)));
|
|
}
|
|
|
|
// slope line overlay
|
|
texel.rgb = texel.rgb * (1.0 - 0.12 * slopenoise_50m - 0.08 * slopenoise_100m);
|
|
|
|
//const vec4 dust_color = vec4 (0.76, 0.71, 0.56, 1.0);
|
|
const vec4 dust_color = vec4 (0.76, 0.65, 0.45, 1.0);
|
|
const vec4 lichen_color = vec4 (0.17, 0.20, 0.06, 1.0);
|
|
|
|
// mix vegetation
|
|
float gradient_factor = smoothstep(0.5, 1.0, steepness);
|
|
texel = mix(texel, lichen_color, gradient_factor * (0.4 * lichen_cover_factor + 0.8 * lichen_cover_factor * 0.5 * (noise_10m + (1.0 - noise_5m))) );
|
|
// mix dust
|
|
texel = mix(texel, dust_color, clamp(0.5 * dust_cover_factor *dust_resistance + 3.0 * dust_cover_factor * dust_resistance *(((noise_1500m - 0.5) * 0.125)+0.125 ),0.0, 1.0) );
|
|
// mix snow
|
|
float snow_mix_factor = 0.0;
|
|
if (msl_altitude +500.0 > snowlevel)
|
|
{
|
|
snow_alpha = smoothstep(0.75, 0.85, abs(steepness));
|
|
snow_mix_factor = snow_texel.a* smoothstep(snowlevel, snowlevel+200.0, snow_alpha * msl_altitude+ (noise_2000m + 0.1 * noise_10m -0.55) *400.0);
|
|
texel = mix(texel, snow_texel, snow_mix_factor);
|
|
}
|
|
|
|
|
|
|
|
|
|
// get distribution of water when terrain is wet
|
|
|
|
float combined_wetness = min(1.0, wetness + intrinsic_wetness);
|
|
float water_threshold1;
|
|
float water_threshold2;
|
|
float water_factor =0.0;
|
|
|
|
|
|
if ((dist < 5000.0)&& (quality_level > 3) && (combined_wetness>0.0))
|
|
{
|
|
water_threshold1 = 1.0-0.5* combined_wetness;
|
|
water_threshold2 = 1.0 - 0.3 * combined_wetness;
|
|
water_factor = smoothstep(water_threshold1, water_threshold2 , (0.3 * (2.0 * (1.0-noise_10m) + (1.0 -noise_5m)) * (1.0 - smoothstep(2000.0, 5000.0, dist))) - 5.0 * (1.0 -steepness));
|
|
}
|
|
|
|
// darken wet terrain
|
|
|
|
texel.rgb = texel.rgb * (1.0 - 0.6 * combined_wetness);
|
|
|
|
|
|
|
|
// light computations
|
|
|
|
|
|
vec4 light_specular = gl_LightSource[0].specular;
|
|
|
|
// If gl_Color.a == 0, this is a back-facing polygon and the
|
|
// normal should be reversed.
|
|
//n = (2.0 * gl_Color.a - 1.0) * normal;
|
|
n = normal;//vec3 (nvec.x, nvec.y, sqrt(1.0 -pow(nvec.x,2.0) - pow(nvec.y,2.0) ));
|
|
n = normalize(n);
|
|
|
|
NdotL = dot(n, lightDir);
|
|
|
|
noisegrad_10m = (noise_10m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),10.0))/0.05;
|
|
noisegrad_5m = (noise_5m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),5.0))/0.05;
|
|
noisegrad_2m = (noise_2m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),2.0))/0.05;
|
|
noisegrad_1m = (noise_1m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),1.0))/0.05;
|
|
|
|
dotnoisegrad_10m = (dotnoise_10m - DotNoise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),10.0 * dot_size,0.5, dot_density))/0.05;
|
|
|
|
|
|
NdotL = NdotL + (noisegrad_10m * detail_fade(10.0, view_angle,dist) + 0.5* noisegrad_5m * detail_fade(5.0, view_angle,dist)) * mix_factor/0.8;
|
|
NdotL = NdotL + 0.15 * noisegrad_2m * mix_factor/0.8 * detail_fade(2.0,view_angle,dist);
|
|
NdotL = NdotL + 0.1 * noisegrad_2m * detail_fade(2.0,view_angle,dist);
|
|
NdotL = NdotL + 0.05 * noisegrad_1m * detail_fade(1.0, view_angle,dist);
|
|
NdotL = NdotL + (1.0-snow_mix_factor) * 0.3* dot_texel.a * (0.5* dotnoisegrad_10m * detail_fade(1.0 * dot_size, view_angle, dist) +0.5 * dotnoisegrad_10m * noise_01m * detail_fade(0.1, view_angle, dist)) ;
|
|
|
|
if (NdotL > 0.0) {
|
|
if (cloud_shadow_flag == 1) {NdotL = NdotL * shadow_func(relPos.x, relPos.y, 0.3 * noise_250m + 0.5 * noise_500m+0.2 * noise_1500m, dist);}
|
|
color += diffuse_term * NdotL;
|
|
NdotHV = max(dot(n, halfVector), 0.0);
|
|
if (gl_FrontMaterial.shininess > 0.0)
|
|
specular.rgb = ((gl_FrontMaterial.specular.rgb * 0.1 + (water_factor * vec3 (1.0, 1.0, 1.0)))
|
|
* light_specular.rgb
|
|
* pow(NdotHV, gl_FrontMaterial.shininess + (20.0 * water_factor)));
|
|
}
|
|
color.a = 1.0;//diffuse_term.a;
|
|
// This shouldn't be necessary, but our lighting becomes very
|
|
// saturated. Clamping the color before modulating by the texture
|
|
// is closer to what the OpenGL fixed function pipeline does.
|
|
color = clamp(color, 0.0, 1.0);
|
|
|
|
if (use_searchlight == 1)
|
|
{
|
|
color.rgb += searchlight(dist);
|
|
}
|
|
if (use_landing_light == 1)
|
|
{
|
|
color.rgb += landing_light(dist, landing_light1_offset);
|
|
}
|
|
if (use_alt_landing_light == 1)
|
|
{
|
|
color.rgb += landing_light(dist, landing_light2_offset);
|
|
}
|
|
|
|
|
|
fragColor = color * texel + specular;
|
|
|
|
|
|
// Rayleigh color shift due to out-scattering
|
|
float rayleigh_length = 0.5 * avisibility * (2.5 - 1.9 * air_pollution)/alt_factor(eye_alt, eye_alt+relPos.z);
|
|
float outscatter = 1.0-exp(-dist/rayleigh_length);
|
|
fragColor.rgb = rayleigh_out_shift(fragColor.rgb,outscatter);
|
|
|
|
// here comes the terrain haze model
|
|
|
|
float delta_z = hazeLayerAltitude - eye_alt;
|
|
|
|
if (dist > 0.04 * min(visibility,avisibility))
|
|
{
|
|
|
|
alt = eye_alt;
|
|
|
|
|
|
float transmission;
|
|
float vAltitude;
|
|
float delta_zv;
|
|
float H;
|
|
float distance_in_layer;
|
|
float transmission_arg;
|
|
|
|
|
|
|
|
|
|
// we solve the geometry what part of the light path is attenuated normally and what is through the haze layer
|
|
|
|
if (delta_z > 0.0) // we're inside the layer
|
|
{
|
|
if (ct < 0.0) // we look down
|
|
{
|
|
distance_in_layer = dist;
|
|
vAltitude = min(distance_in_layer,min(visibility, avisibility)) * ct;
|
|
delta_zv = delta_z - vAltitude;
|
|
}
|
|
else // we may look through upper layer edge
|
|
{
|
|
H = dist * ct;
|
|
if (H > delta_z) {distance_in_layer = dist/H * delta_z;}
|
|
else {distance_in_layer = dist;}
|
|
vAltitude = min(distance_in_layer,visibility) * ct;
|
|
delta_zv = delta_z - vAltitude;
|
|
}
|
|
}
|
|
else // we see the layer from above, delta_z < 0.0
|
|
{
|
|
H = dist * -ct;
|
|
if (H < (-delta_z)) // we don't see into the layer at all, aloft visibility is the only fading
|
|
{
|
|
distance_in_layer = 0.0;
|
|
delta_zv = 0.0;
|
|
}
|
|
else
|
|
{
|
|
vAltitude = H + delta_z;
|
|
distance_in_layer = vAltitude/H * dist;
|
|
vAltitude = min(distance_in_layer,visibility) * (-ct);
|
|
delta_zv = vAltitude;
|
|
}
|
|
}
|
|
|
|
// blur of the haze layer edge
|
|
|
|
float blur_thickness = 50.0;
|
|
float cphi = dot(vec3(0.0, 1.0, 0.0), relPos)/dist;
|
|
float ctlayer = delta_z/dist-0.01 + 0.02 * Noise2D(vec2(cphi,1.0),0.1) -0.01;
|
|
float ctblur = 0.035 ;
|
|
|
|
float blur_dist;
|
|
|
|
if (abs(delta_z) < 400.0)
|
|
{
|
|
blur_dist = dist * (1.0-smoothstep(0.0,300.0,-delta_z)) * smoothstep(-400.0,-200.0, -delta_z);
|
|
blur_dist = blur_dist * smoothstep(ctlayer-4.0*ctblur, ctlayer-ctblur, ct) * (1.0-smoothstep(ctlayer+0.5*ctblur, ctlayer+ctblur, ct));
|
|
distance_in_layer = max(distance_in_layer, blur_dist);
|
|
}
|
|
|
|
|
|
// ground haze cannot be thinner than aloft visibility in the model,
|
|
// so we need to use aloft visibility otherwise
|
|
|
|
|
|
transmission_arg = (dist-distance_in_layer)/avisibility;
|
|
|
|
|
|
float eqColorFactor;
|
|
|
|
|
|
|
|
if (visibility < avisibility)
|
|
{
|
|
if (quality_level > 3)
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/(1.0 * visibility + 1.0 * visibility * fogstructure * 0.06 * (noise_1500m + noise_2000m -1.0) ));
|
|
|
|
}
|
|
else
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/visibility);
|
|
}
|
|
// this combines the Weber-Fechner intensity
|
|
eqColorFactor = 1.0 - 0.1 * delta_zv/visibility - (1.0 - effective_scattering);
|
|
|
|
}
|
|
else
|
|
{
|
|
if (quality_level > 3)
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/(1.0 * avisibility + 1.0 * avisibility * fogstructure * 0.06 * (noise_1500m + noise_2000m - 1.0) ));
|
|
}
|
|
else
|
|
{
|
|
transmission_arg = transmission_arg + (distance_in_layer/avisibility);
|
|
}
|
|
// this combines the Weber-Fechner intensity
|
|
eqColorFactor = 1.0 - 0.1 * delta_zv/avisibility - (1.0 - effective_scattering);
|
|
}
|
|
|
|
|
|
|
|
transmission = fog_func(transmission_arg, alt);
|
|
|
|
// there's always residual intensity, we should never be driven to zero
|
|
if (eqColorFactor < 0.2) eqColorFactor = 0.2;
|
|
|
|
|
|
float lightArg = (terminator-yprime_alt)/100000.0;
|
|
|
|
vec3 hazeColor;
|
|
|
|
hazeColor.b = light_func(lightArg, 1.330e-05, 0.264, 2.527, 1.08e-05, 1.0);
|
|
hazeColor.g = light_func(lightArg, 3.931e-06, 0.264, 3.827, 7.93e-06, 1.0);
|
|
hazeColor.r = light_func(lightArg, 8.305e-06, 0.161, 3.827, 3.04e-05, 1.0);
|
|
|
|
|
|
// now dim the light for haze
|
|
eShade = 0.9 * smoothstep(terminator_width+ terminator, -terminator_width + terminator, yprime_alt) + 0.1;
|
|
|
|
// Mie-like factor
|
|
|
|
if (lightArg < 10.0)
|
|
{
|
|
intensity = length(hazeColor);
|
|
float mie_magnitude = 0.5 * smoothstep(350000.0, 150000.0, terminator-sqrt(2.0 * EarthRadius * terrain_alt));
|
|
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)) );
|
|
}
|
|
|
|
intensity = length(hazeColor);
|
|
|
|
if (intensity > 0.0) // this needs to be a condition, because otherwise hazeColor doesn't come out correctly
|
|
{
|
|
|
|
|
|
// high altitude desaturation of the haze color
|
|
hazeColor = intensity * normalize (mix(hazeColor, intensity * vec3 (1.0,1.0,1.0), 0.7* smoothstep(5000.0, 50000.0, alt)));
|
|
|
|
// blue hue of haze
|
|
hazeColor.x = hazeColor.x * 0.83;
|
|
hazeColor.y = hazeColor.y * 0.9;
|
|
|
|
|
|
// additional blue in indirect light
|
|
float fade_out = max(0.65 - 0.3 *overcast, 0.45);
|
|
intensity = length(hazeColor);
|
|
hazeColor = intensity * normalize(mix(hazeColor, 1.5* shadedFogColor, 1.0 -smoothstep(0.25, fade_out,eShade) ));
|
|
|
|
// change haze color to blue hue for strong fogging
|
|
hazeColor = intensity * normalize(mix(hazeColor, shadedFogColor, (1.0-smoothstep(0.5,0.9,eqColorFactor))));
|
|
|
|
|
|
|
|
// reduce haze intensity when looking at shaded surfaces, only in terminator region
|
|
float shadow = mix( min(1.0 + dot(n,lightDir),1.0), 1.0, 1.0-smoothstep(0.1, 0.4, transmission));
|
|
hazeColor = mix(shadow * hazeColor, hazeColor, 0.3 + 0.7* smoothstep(250000.0, 400000.0, terminator));
|
|
}
|
|
|
|
|
|
// blue Rayleigh scattering with distance
|
|
|
|
float rShade = 0.9 * smoothstep(terminator_width+ terminator, -terminator_width + terminator, yprime_alt-340000.0) + 0.1;
|
|
float lightIntensity = length(diffuse_term.rgb)/1.73 * rShade;
|
|
vec3 rayleighColor = vec3 (0.17, 0.52, 0.87) * lightIntensity;
|
|
float rayleighStrength = rayleigh_in_func(dist, air_pollution, avisibility/max(lightIntensity,0.05), eye_alt, eye_alt + relPos.z);
|
|
fragColor.rgb = mix(fragColor.rgb, rayleighColor,rayleighStrength);
|
|
|
|
// finally, mix fog in
|
|
|
|
|
|
fragColor.rgb = mix(eqColorFactor * hazeColor * eShade , fragColor.rgb,transmission);
|
|
|
|
|
|
gl_FragColor = fragColor;
|
|
|
|
|
|
}
|
|
else // if dist < threshold no fogging at all
|
|
{
|
|
|
|
// blue Rayleigh scattering with distance
|
|
|
|
float rShade = 0.9 * smoothstep(terminator_width+ terminator, -terminator_width + terminator, yprime_alt-340000.0) + 0.1;
|
|
float lightIntensity = length(diffuse_term.rgb)/1.73 * rShade;
|
|
vec3 rayleighColor = vec3 (0.17, 0.52, 0.87) * lightIntensity;
|
|
float rayleighStrength = rayleigh_in_func(dist, air_pollution, avisibility/max(lightIntensity,0.05), eye_alt, eye_alt + relPos.z);
|
|
fragColor.rgb = mix(fragColor.rgb, rayleighColor,rayleighStrength);
|
|
|
|
gl_FragColor = fragColor;
|
|
}
|
|
|
|
|
|
|
|
}
|
|
|