diff --git a/Effects/cliffs.eff b/Effects/cliffs.eff new file mode 100644 index 000000000..e9fcaa4ec --- /dev/null +++ b/Effects/cliffs.eff @@ -0,0 +1,589 @@ + + + Effects/cliffs + Effects/terrain-default + + + 0.71 0.49 0.40 + 0.42 0.38 0.37 + 0.4 + 0.0 + 1.0 + 0.6 + 7.0 + 0.8 + 1.0 + 0 + + + + + + + + + + + + /sim/rendering/shaders/skydome + + + 6.0 + /sim/rendering/shaders/landmass + + + 6.0 + /sim/rendering/shaders/transition + + + + + 2.0 + + + + GL_ARB_shader_objects + GL_ARB_shading_language_100 + GL_ARB_vertex_shader + GL_ARB_fragment_shader + + + + + + + + true + + material/ambient + material/diffuse + material/specular + material/emissive + material/shininess + ambient-and-diffuse + + transparent + transparent + smooth + back + + render-bin/bin-number + render-bin/bin-name + + + Shaders/terrain-ALS-ultra.vert + Shaders/filters-ALS.vert + Shaders/cliffs-ALS.frag + Shaders/cloud-shadowfunc.frag + Shaders/noise.frag + Shaders/hazes.frag + Shaders/secondary_lights.frag + Shaders/filters-ALS.frag + + + intrinsic_wetness + float + intrinsic_wetness + + + slopeline_strength + float + slopeline_strength + + + rock_strata + int + rock_strata + + + transition_model + float + transition_model + + + overlay_bias + float + overlay-bias + + + crack_depth + float + crack-depth + + + crack_pattern_stretch + float + crack-pattern-stretch + + + grain_fade_power + float + grain-fade-power + + + rock_brightness + float + rock-brightness + + + dust_resistance + float + dust_resistance + + + visibility + float + visibility + + + avisibility + float + avisibility + + + hazeLayerAltitude + float + lthickness + + + scattering + float + scattering + + + ground_scattering + float + ground_scattering + + + terminator + float + terminator + + + terrain_alt + float + terrain_alt + + + overcast + float + overcast + + + eye_alt + float + eye_alt + + + eye_lat + float + eye_lat + + + eye_lon + float + eye_lon + + + snowlevel + float + snow_level + + + snow_thickness_factor + float + snow_thickness_factor + + + dust_cover_factor + float + dust_cover_factor + + + lichen_cover_factor + float + lichen_cover_factor + + + wetness + float + wetness + + + fogstructure + float + fogstructure + + + cloud_self_shading + float + cloud_self_shading + + + moonlight + float + moonlight + + + contrast + float + contrast + + + overlay_alpha + float + overlay-alpha + + + base_color + float-vec3 + base-color + + + overlay_color + float-vec3 + overlay-color + + + air_pollution + float + air_pollution + + + view_pitch_offset + float + view_pitch_offset + + + view_heading_offset + float + view_heading_offset + + + field_of_view + float + view_fov + + + landing_light1_offset + float + landing_light1_offset + + + landing_light2_offset + float + landing_light2_offset + + + landing_light3_offset + float + landing_light3_offset + + + + gamma + float + gamma + + + brightness + float + brightness + + + use_night_vision + bool + use_night_vision + + + use_IR_vision + bool + use_IR_vision + + + use_filtering + bool + use_filtering + + + delta_T + float + delta_T + + + fact_grey + float + fact_grey + + + fact_black + float + fact_black + + + + cloudpos1_x + float + cloudpos1_x + + + cloudpos1_y + float + cloudpos1_y + + + cloudpos2_x + float + cloudpos2_x + + + cloudpos2_y + float + cloudpos2_y + + + cloudpos3_x + float + cloudpos3_x + + + cloudpos3_y + float + cloudpos3_y + + + cloudpos4_x + float + cloudpos4_x + + + cloudpos4_y + float + cloudpos4_y + + + cloudpos5_x + float + cloudpos5_x + + + cloudpos5_y + float + cloudpos5_y + + + cloudpos6_x + float + cloudpos6_x + + + cloudpos6_y + float + cloudpos6_y + + + cloudpos7_x + float + cloudpos7_x + + + cloudpos7_y + float + cloudpos7_y + + + cloudpos8_x + float + cloudpos8_x + + + cloudpos8_y + float + cloudpos8_y + + + cloudpos9_x + float + cloudpos9_x + + + cloudpos9_y + float + cloudpos9_y + + + cloudpos10_x + float + cloudpos10_x + + + cloudpos10_y + float + cloudpos10_y + + + cloudpos11_x + float + cloudpos11_x + + + cloudpos11_y + float + cloudpos11_y + + + cloudpos12_x + float + cloudpos12_x + + + cloudpos12_y + float + cloudpos12_y + + + cloudpos13_x + float + cloudpos13_x + + + cloudpos13_y + float + cloudpos13_y + + + cloudpos14_x + float + cloudpos14_x + + + cloudpos14_y + float + cloudpos14_y + + + cloudpos15_x + float + cloudpos15_x + + + cloudpos15_y + float + cloudpos15_y + + + cloudpos16_x + float + cloudpos16_x + + + cloudpos16_y + float + cloudpos16_y + + + cloudpos17_x + float + cloudpos17_x + + + cloudpos17_y + float + cloudpos17_y + + + cloudpos18_x + float + cloudpos18_x + + + cloudpos18_y + float + cloudpos18_y + + + cloudpos19_x + float + cloudpos19_x + + + cloudpos19_y + float + cloudpos19_y + + + cloudpos20_x + float + cloudpos20_x + + + cloudpos20_y + float + cloudpos20_y + + + use_searchlight + int + use_searchlight + + + use_landing_light + int + use_landing_light + + + use_alt_landing_light + int + use_alt_landing_light + + + display_xsize + int + display_xsize + + + display_ysize + int + display_ysize + + + wind_effects + int + wind_effects + + + cloud_shadow_flag + int + cloud_shadow_flag + + + colorMode + int + 2 + + + + lequal + + + + + + diff --git a/Shaders/cliffs-ALS.frag b/Shaders/cliffs-ALS.frag new file mode 100644 index 000000000..956b93159 --- /dev/null +++ b/Shaders/cliffs-ALS.frag @@ -0,0 +1,620 @@ +// -*-C++-*- +#version 120 + +// adapted by James Hester 2018, based on rock-ALS.frag +// by Thorsten Renk. +// 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 float steepness; +varying vec2 grad_dir; + + +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 dust_cover_factor; +uniform float lichen_cover_factor; +uniform float wetness; +uniform float fogstructure; +uniform float cloud_self_shading; +uniform float contrast; +uniform float air_pollution; +uniform float intrinsic_wetness; +uniform float transition_model; +uniform float overlay_bias; +uniform float crack_depth; +uniform float crack_pattern_stretch; +uniform float grain_fade_power; +uniform float rock_brightness; +uniform float overlay_alpha; +uniform float dust_resistance; +uniform float slopeline_strength; +uniform float landing_light1_offset; +uniform float landing_light2_offset; +uniform float landing_light3_offset; +uniform float osg_SimulationTime; + +uniform vec3 base_color; +uniform vec3 overlay_color; + +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 Noise2D(in vec2 coord, in float wavelength); +float Noise3D(in vec3 coord, in float wavelength); +float VoronoiNoise2D(in vec2 coord, in float wavelength, in float xrand, in float yrand); +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); +float light_distance_fading(in float dist); +float fog_backscatter(in float avisibility); + +vec3 rayleigh_out_shift(in vec3 color, in float outscatter); +vec3 get_hazeColor(in float light_arg); +vec3 searchlight(); +vec3 landing_light(in float offset, in float offsetv); +vec3 filter_combined (in vec3 color) ; + +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() +{ + + +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); +// horizontal distance using texture coordinate +float horiz_coord = gl_TexCoord[0].s * 1000.0; +// angle of view vector with horizon +float ct = dot(vec3(0.0, 0.0, 1.0), relPos)/dist; +// float altitude of fragment above base of cliff +float cliff_altitude = gl_TexCoord[0].t * 1000.0; + + + vec3 shadedFogColor = vec3(0.55, 0.67, 0.88); +// 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 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; + + + +// Perlin noise, distance along cliff in texture coordinate instead of x,y + +float noise_100m = Noise2D(vec2(horiz_coord,cliff_altitude),100.0); +float noise_50m = Noise2D(vec2(horiz_coord,cliff_altitude), 50.0); +float noise_25m = Noise2D(vec2(horiz_coord,cliff_altitude), 25.0); +float noise_10m = Noise2D(vec2(horiz_coord,cliff_altitude), 10.0); +float noise_5m = Noise2D(vec2(horiz_coord,cliff_altitude) ,5.0); +float noise_2m = Noise2D(vec2(horiz_coord,cliff_altitude) ,2.0); +float noise_1m = Noise2D(vec2(horiz_coord,cliff_altitude) ,1.0); +float noise_05m = Noise2D(vec2(horiz_coord,cliff_altitude),0.5); +float noise_02m = Noise2D(vec2(horiz_coord,cliff_altitude),0.2); +float noise_01m = Noise2D(vec2(horiz_coord,cliff_altitude), 0.1); + +float noisegrad_10m; +float noisegrad_5m; +float noisegrad_2m; +float noisegrad_1m; +float noisegrad_05m; +float noisegrad_02m; +float noisegrad_01m; + + + + + +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 = 0.0; +float dotnoise_10m = 0.0; +float dotnoise_15m = 0.0; + +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); + + + + + + +// get the texels + + float noise_term; + float local_autumn_factor; + + // 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))); + + // strata noise + + float stratnoise_50m; + float stratnoise_10m; + + if (rock_strata==1) + { + stratnoise_50m = Strata3D(vec3 (rawPos.x, rawPos.y, cliff_altitude), 50.0, 0.2); + stratnoise_10m = Strata3D(vec3 (rawPos.x, rawPos.y, cliff_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); + } + + + + + + + + // procedural rock texture generation + + texel.rgb = base_color; + + // use powers of Perlin noise to generate the base pattern + + float grainy_noise; + float fade_norm; + + float gfp = grain_fade_power; + float gfptmp; + + //grainy_noise = (0.5 * (1.0-slopenoise_100m) + 0.5 *noise_50m) + gfp * (0.5 * slopenoise_50m + 0.5 * noise_25m); + grainy_noise = (0.5 *noise_50m) + gfp * ( 0.5 * noise_25m); + fade_norm = 1.0+gfp; + + gfptmp = gfp * gfp; + grainy_noise += noise_10m * gfptmp * detail_fade(10.0, view_angle, dist) ; + fade_norm += gfptmp * detail_fade(10.0, view_angle, dist) ; + + gfptmp = gfptmp * gfp; + grainy_noise += noise_5m * gfptmp * detail_fade(5.0, view_angle, dist) ; + fade_norm += gfptmp * detail_fade(5.0, view_angle, dist) ; + + gfptmp = gfptmp * gfp; + grainy_noise += noise_2m * gfptmp * detail_fade(2.0, view_angle, dist) ; + fade_norm += gfptmp * detail_fade(2.0, view_angle, dist) ; + + gfptmp = gfptmp * gfp; + grainy_noise += noise_1m * gfptmp * detail_fade(1.0, view_angle, dist) ; + fade_norm += gfptmp * detail_fade(1.0, view_angle, dist) ; + + gfptmp = gfptmp * gfp; + grainy_noise += noise_05m * gfptmp * detail_fade(0.5, view_angle, dist) ; + fade_norm += gfptmp * detail_fade(0.5, view_angle, dist) ; + + grainy_noise = grainy_noise/fade_norm; + grainy_noise = smoothstep(-0.2, 1.2, grainy_noise); + + // generate the crack pattern from isovalue lines of stretched Perlin noise + + float cnoise_500m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 500.0); + float cnoise_250m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 250.0); + float cnoise_100m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 100.0); + float cnoise_50m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 50.0); + float cnoise_25m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 25.0); + float cnoise_10m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 10.0); + float cnoise_5m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 5.0); + float cnoise_2m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 2.0); + float cnoise_1m = Noise2D(vec2(horiz_coord+10.0, crack_pattern_stretch * cliff_altitude), 1.0); + + float crack_noise; + float crack_factor; + float crack_size; + float scrack_noise; + float scrack_size; + + crack_noise = cnoise_500m + 0.65 * cnoise_250m + 0.42 * cnoise_100m * detail_fade(50.0, view_angle, dist) ; + crack_noise = crack_noise + 0.27 * cnoise_50m * detail_fade(25.0, view_angle, dist) ; + crack_noise = crack_noise + 0.17 * cnoise_25m * detail_fade(10.0, view_angle, dist) ; + crack_noise = crack_noise + 0.11 * cnoise_10m * detail_fade(5.0, view_angle, dist) ; + crack_noise = 0.381 * crack_noise; + + + + scrack_noise = cnoise_10m + 0.65 * cnoise_5m * detail_fade(5.0, view_angle, dist); + scrack_noise = scrack_noise + 0.3 * cnoise_2m + 0.1 * cnoise_1m * detail_fade(1.0, view_angle, dist); + scrack_noise = 0.48 * scrack_noise; + + crack_size = 0.02 +0.00001 * dist; + crack_factor = smoothstep(0.5-crack_size,0.50,crack_noise) * (1.0-smoothstep(0.51,0.51+crack_size,crack_noise)); + //crack_factor = step(0.5-0.2*crack_size,crack_noise) * (1.0-step(0.5+0.2*crack_size,crack_noise)); + + crack_size *= 0.5; + crack_factor += smoothstep(0.42,0.42+crack_size,crack_noise) * (1.0-smoothstep(0.43,0.43+crack_size,crack_noise)); + + scrack_size = crack_size * 4.0; + crack_factor += 0.75 * smoothstep(0.5-scrack_size,0.50,scrack_noise) * (1.0-smoothstep(0.51,0.51+scrack_size,scrack_noise))* (1.0- smoothstep(250.0,1000.0,dist)); + + + crack_factor = crack_factor * min(1.0,0.03/crack_size); + + + +// distribution of overlay color + + + float overlay_noise; + float overlay_factor; + + overlay_noise = 0.381 * (noise_50m + 0.65 * noise_25m + 0.42 * noise_10m + 0.27 * noise_5m + 0.17 * noise_2m + 0.11 * noise_1m); + overlay_noise = overlay_noise + 0.1 * (smoothstep(0.8,0.9, steepness)); + + overlay_factor = smoothstep(0.7, 0.72, overlay_noise + overlay_bias) + (1.0 - smoothstep(0.2, 0.22, overlay_noise - overlay_bias)); + + + +// merge the noise components + + //grainy_noise = grainy_noise * (1.0-crack_depth * crack_factor) + 0.5 * crack_depth * crack_factor; + texel.rgb = ((1.0 - contrast) + contrast * grainy_noise ) * texel.rgb; + texel.rgb = mix(texel.rgb, overlay_color.rgb,overlay_alpha * overlay_factor); + texel.rgb = texel.rgb * ((1.0-crack_depth) +crack_depth*(1.0-crack_factor * (0.5 + 0.5 * noise_50m) )); + + texel.rgb = texel.rgb * rock_brightness; + + texel.rgb = texel.rgb * (1.0 + 0.4 * (noise_01m-0.5) * detail_fade(0.1, view_angle, dist)) ; + + +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) ); + +// 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) && (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; + 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; + noisegrad_05m = (noise_05m - Noise2D(rawPos.xy+ 0.05 * normalize(lightDir.xy),0.5))/0.05; + + + dotnoisegrad_10m = 0.0; + + float fresnel; + + 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); + + fresnel = 1.0 + 5.0 * (1.0-smoothstep(0.0,0.2, dot(normalize(ecViewdir),n))); + + //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, max(gl_FrontMaterial.shininess,4.0) + (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); + + vec3 secondary_light = vec3 (0.0,0.0,0.0); + + if (use_searchlight == 1) + { + secondary_light += searchlight(); + } + if (use_landing_light == 1) + { + secondary_light += landing_light(landing_light1_offset, landing_light3_offset); + } + if (use_alt_landing_light == 1) + { + secondary_light += landing_light(landing_light2_offset, landing_light3_offset); + } + color.rgb +=secondary_light * light_distance_fading(dist); + + + fragColor = color * texel + specular; + +float lightArg = (terminator-yprime_alt)/100000.0; +vec3 hazeColor = get_hazeColor(lightArg); + + + +// 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); + +// Rayleigh color shift due to in-scattering + + float rShade = 1.0 - 0.9 * smoothstep(-terminator_width+ terminator, terminator_width + terminator, yprime_alt + 420000.0); + float lightIntensity = length(hazeColor * effective_scattering) * 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); + + +// here comes the terrain haze model + + +float delta_z = hazeLayerAltitude - eye_alt; + +float mvisibility = min(visibility,avisibility); + +if (dist > 0.04 * mvisibility) + +{ + +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,mvisibility) * 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) + { + transmission_arg = transmission_arg + (distance_in_layer/(1.0 * visibility + 1.0 * visibility * fogstructure * 0.06 * (noise_1500m + noise_2000m -1.0) )); + // this combines the Weber-Fechner intensity + eqColorFactor = 1.0 - 0.1 * delta_zv/visibility - (1.0 - effective_scattering); + } +else + { + transmission_arg = transmission_arg + (distance_in_layer/(1.0 * avisibility + 1.0 * avisibility * fogstructure * 0.06 * (noise_1500m + noise_2000m - 1.0) )); + // 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; + + + + + + + +// now dim the light for haze +eShade = 1.0 - 0.9 * smoothstep(-terminator_width+ terminator, terminator_width + terminator, yprime_alt); + +// 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)); + } + +// don't let the light fade out too rapidly +lightArg = (terminator + 200000.0)/100000.0; +float minLightIntensity = min(0.2,0.16 * lightArg + 0.5); +vec3 minLight = minLightIntensity * vec3 (0.2, 0.3, 0.4); + +hazeColor.rgb *= eqColorFactor * eShade; +hazeColor.rgb = max(hazeColor.rgb, minLight.rgb); + + +fragColor.rgb = mix(hazeColor + secondary_light * fog_backscatter(mvisibility), fragColor.rgb,transmission); + +} + +fragColor.rgb = filter_combined(fragColor.rgb); + +gl_FragColor = fragColor; + + +} +