// -*-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 ecViewdir; uniform sampler2D texture; uniform sampler2D NormalTex; uniform sampler2D mix_texture; uniform sampler2D grain_texture; 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 filter_threshold; uniform float filter_transition; uniform float size_base; uniform float size_overlay; uniform float size_grain; uniform float strength_05m; uniform float strength_1m; uniform float strength_2m; uniform float strength_5m; uniform float strength_10m; uniform float relief_strength; uniform float grain_strength; uniform float bias_center_strength; uniform float wetness; uniform float fogstructure; uniform float snow_thickness_factor; uniform float cloud_self_shading; uniform float landing_light1_offset; uniform float landing_light2_offset; uniform float landing_light3_offset; uniform float air_pollution; uniform int quality_level; uniform int tquality_level; uniform int cloud_shadow_flag; uniform int bias_center; 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 fog_func (in float targ, in float 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); float rayleigh_in_func(in float dist, in float air_pollution, in float avisibility, in float eye_alt, in float vertex_alt); vec3 searchlight(); vec3 landing_light(in float offset, in float offsetv); vec3 rayleigh_out_shift(in vec3 color, in float outscatter); vec3 get_hazeColor(in float light_arg); 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); // angle of view vector with horizon float ct = dot(vec3(0.0, 0.0, 1.0), relPos)/dist; 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; if (quality_level<6) {halfVector = gl_LightSource[0].halfVector.xyz;} else {halfVector = normalize(normalize(lightDir) + normalize(ecViewdir));} vec4 texel; vec4 snow_texel; vec4 mix_texel; vec4 grain_texel; vec4 fragColor; vec4 specular = vec4(0.0); float intensity; // 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 float noise_01m; float noise_05m = Noise2D(rawPos.xy, 0.5); float noise_1m = Noise2D(rawPos.xy, 1.0); float noise_2m = Noise2D(rawPos.xy, 2.0); float noise_10m = Noise2D(rawPos.xy, 10.0); float noise_5m = Noise2D(rawPos.xy ,5.0); float noisegrad_10m; float noisegrad_5m; float noise_50m = Noise2D(rawPos.xy, 50.0);; float noise_250m; float noise_500m = Noise2D(rawPos.xy, 500.0); float noise_1500m = Noise2D(rawPos.xy, 1500.0); float noise_2000m = Noise2D(rawPos.xy, 2000.0); // // get the texels //texel = texture2D(texture, gl_TexCoord[0].st); //mix_texel = texture2D(mix_texture, gl_TexCoord[0].st * 5.0); texel = texture2D(texture, rawPos * 1.0/size_base); mix_texel = texture2D(mix_texture, rawPos * 1.0/size_overlay); grain_texel = texture2D(grain_texture, rawPos * 1.0/size_grain); vec4 nmap = texture2D(NormalTex, gl_TexCoord[0].st * 8.0); //vec4 nmap = texture2D(NormalTex, rawPos * 0.01); vec3 N = nmap.rgb * 2.0 - 1.0; float distortion_factor = 1.0; vec2 stprime; int flag = 1; int mix_flag = 1; float noise_term; float snow_alpha; //noise_term = smoothstep(overlay_limit ,1.0,noise_1m); //noise_term = smoothstep(overlay_limit, 1.0, 0.5 * noise_1m + 0.5 * noise_10m); noise_term = strength_05m * noise_05m; noise_term += strength_1m * noise_1m; noise_term += strength_2m * noise_2m; noise_term += strength_5m * noise_5m; noise_term += strength_10m * noise_10m; if (bias_center == 1) { float centerness = smoothstep(0.02, 0.1, (0.14 - abs(gl_TexCoord[0].s - 0.14))); centerness *= smoothstep(0.05, 0.15, gl_TexCoord[0].t); centerness = 1.0 - centerness; noise_term *= (1.0 - bias_center_strength) + bias_center_strength * centerness; noise_term = clamp(noise_term, 0.0, 1.0); } float filtered_noise_term = smoothstep(filter_threshold, filter_threshold + filter_transition, noise_term); texel = mix(texel, mix_texel, filtered_noise_term); texel.rgb = mix(texel.rgb, grain_texel.rgb, grain_strength * grain_texel.a * (1.0 - noise_term));// * (1.0-smoothstep(2000.0,5000.0, dist))); //float view_angle = abs(dot(normal, normalize(ecViewdir))); //if ((quality_level > 3)&&(relPos.z + eye_alt +500.0 > snowlevel)) if (quality_level > 3) { float sfactor; noise_01m = Noise2D(rawPos.xy,0.1); snow_texel = vec4 (0.95, 0.95, 0.95, 1.0) * (0.9 + 0.1* noise_50m + 0.1* (1.0 - noise_10m) ); snow_texel.a = 1.0; noise_term = 0.1 * (noise_50m-0.5); sfactor = 1.0;//sqrt(2.0 * (1.0-steepness)/0.03) + abs(ct)/0.15; noise_term = noise_term + 0.2 * (noise_10m -0.5) * (1.0 - smoothstep(10000.0*sfactor, 16000.0*sfactor, dist) ) ; noise_term = noise_term + 0.3 * (noise_5m -0.5) * (1.0 - smoothstep(1200.0 * sfactor, 2000.0 * sfactor, dist) ) ; noise_term = noise_term + 0.3 * (noise_1m -0.5) * (1.0 - smoothstep(500.0 * sfactor, 1000.0 *sfactor, dist) ); noise_term = noise_term + 0.3 * (noise_01m -0.5) * (1.0 - smoothstep(20.0 * sfactor, 100.0 *sfactor, dist) ); snow_texel.a = snow_texel.a * 0.2+0.8* smoothstep(0.2,0.8, 0.3 +noise_term + 0.2*snow_thickness_factor +0.0001*(relPos.z +eye_alt -snowlevel) ); } const vec4 dust_color = vec4 (0.76, 0.71, 0.56, 1.0); const vec4 lichen_color = vec4 (0.17, 0.20, 0.06, 1.0);; //float snow_alpha; if (quality_level > 3) { // mix vegetation texel = mix(texel, lichen_color, 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 + 3.0 * dust_cover_factor * (((noise_1500m - 0.5) * 0.125)+0.125 ),0.0, 1.0) ); // mix snow if (relPos.z + eye_alt +500.0 > snowlevel) { snow_alpha = smoothstep(0.75, 0.85, abs(steepness)); texel = mix(texel, snow_texel, snow_texel.a* smoothstep(snowlevel, snowlevel+200.0, snow_alpha * (relPos.z + eye_alt)+ (noise_2000m + 0.1 * noise_10m -0.55) *400.0)); } } // get distribution of water when terrain is wet float water_threshold1; float water_threshold2; float water_factor =0.0; if ((dist < 5000.0)&& (quality_level > 3) && (wetness>0.0)) { water_threshold1 = 1.0-0.5* wetness; water_threshold2 = 1.0 - 0.3 * 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)); water_factor = smoothstep(water_threshold1, water_threshold2 , 0.5 * (noise_5m + (1.0 -noise_1m))) * (1.0 - smoothstep(1000.0, 3000.0, dist)); } // darken wet terrain texel.rgb = texel.rgb * (1.0 - 0.6 * wetness - 0.1 * water_factor); // 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); if (quality_level > 4) { NdotL = NdotL + (3.0 * N.r + 0.1 * (noise_01m-0.5))* (1.0 - water_factor) * relief_strength; //NdotL = NdotL + 3.0 * N.r + 0.1 * (noise_01m-0.5) ; } if (NdotL > 0.0) { if (cloud_shadow_flag == 1) {NdotL = NdotL * shadow_func(relPos.x, relPos.y, 1.0, dist);} color += diffuse_term * NdotL; NdotHV = max(dot(n, halfVector), 0.0); //if (gl_FrontMaterial.shininess > 0.0) specular.rgb = ((gl_FrontMaterial.specular.rgb + (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); vec3 secondary_light = vec3 (0.0,0.0,0.0); if (use_searchlight == 1) { secondary_light.rgb += 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 shifts if ((quality_level > 5) && (tquality_level > 5)) { 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; } } // 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; // 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); } gl_FragColor = fragColor; }