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- !function(n){function e(i){if(t[i])return t[i].exports;var o=t[i]={exports:{},id:i,loaded:!1};return n[i].call(o.exports,o,o.exports,e),o.loaded=!0,o.exports}var t={};return e.m=n,e.c=t,e.p="",e(0)}([function(n,e,t){var i=t(2),o=t(1);AFRAME.registerShader("sunSky",{schema:{luminance:{"default":1,max:0,min:2,is:"uniform"},mieCoefficient:{"default":.005,min:0,max:.1,is:"uniform"},mieDirectionalG:{"default":.8,min:0,max:1,is:"uniform"},reileigh:{"default":1,max:0,min:4,is:"uniform"},sunPosition:{type:"vec3","default":"0 0 -1",is:"uniform"},turbidity:{"default":2,max:0,min:20,is:"uniform"}},vertexShader:i,fragmentShader:o}),AFRAME.registerPrimitive("a-sun-sky",{defaultComponents:{geometry:{primitive:"sphere",radius:5e3,segmentsWidth:64,segmentsHeight:20},material:{shader:"sunSky"},scale:"-1 1 1"},mappings:{luminance:"material.luminance",mieCoefficient:"material.mieCoefficient",mieDirectionalG:"material.mieDirectionalG",reileigh:"material.reileigh",sunPosition:"material.sunPosition",turbidity:"material.turbidity"}})},function(n,e){n.exports="uniform sampler2D skySampler;\nuniform vec3 sunPosition;\nvarying vec3 vWorldPosition;\n\nvec3 cameraPos = vec3(0., 0., 0.);\n\nuniform float luminance;\nuniform float turbidity;\nuniform float reileigh;\nuniform float mieCoefficient;\nuniform float mieDirectionalG;\n\n// constants for atmospheric scattering\nconst float e = 2.71828182845904523536028747135266249775724709369995957;\nconst float pi = 3.141592653589793238462643383279502884197169;\n\nconst float n = 1.0003; // refractive index of air\nconst float N = 2.545E25; // number of molecules per unit volume for air at\n// 288.15K and 1013mb (sea level -45 celsius)\nconst float pn = 0.035; // depolatization factor for standard air\n\n// wavelength of used primaries, according to preetham\nconst vec3 lambda = vec3(680E-9, 550E-9, 450E-9);\n\n// mie stuff\n// K coefficient for the primaries\nconst vec3 K = vec3(0.686, 0.678, 0.666);\nconst float v = 4.0;\n\n// optical length at zenith for molecules\nconst float rayleighZenithLength = 8.4E3;\nconst float mieZenithLength = 1.25E3;\nconst vec3 up = vec3(0.0, 1.0, 0.0);\n\nconst float EE = 1000.0;\nconst float sunAngularDiameterCos = 0.999956676946448443553574619906976478926848692873900859324;\n// 66 arc seconds -> degrees, and the cosine of that\n\n// earth shadow hack\nconst float cutoffAngle = pi/1.95;\nconst float steepness = 1.5;\n\nvec3 totalRayleigh(vec3 lambda)\n{\n return (8.0 * pow(pi, 3.0) * pow(pow(n, 2.0) - 1.0, 2.0) * (6.0 + 3.0 * pn)) / (3.0 * N * pow(lambda, vec3(4.0)) * (6.0 - 7.0 * pn));\n}\n\n// see http://blenderartists.org/forum/showthread.php?321110-Shaders-and-Skybox-madness\n// A simplied version of the total Rayleigh scattering to works on browsers that use ANGLE\nvec3 simplifiedRayleigh()\n{\n return 0.0005 / vec3(94, 40, 18);\n}\n\nfloat rayleighPhase(float cosTheta)\n{\n return (3.0 / (16.0*pi)) * (1.0 + pow(cosTheta, 2.0));\n}\n\nvec3 totalMie(vec3 lambda, vec3 K, float T)\n{\n float c = (0.2 * T ) * 10E-18;\n return 0.434 * c * pi * pow((2.0 * pi) / lambda, vec3(v - 2.0)) * K;\n}\n\nfloat hgPhase(float cosTheta, float g)\n{\n return (1.0 / (4.0*pi)) * ((1.0 - pow(g, 2.0)) / pow(1.0 - 2.0*g*cosTheta + pow(g, 2.0), 1.5));\n}\n\nfloat sunIntensity(float zenithAngleCos)\n{\n return EE * max(0.0, 1.0 - exp(-((cutoffAngle - acos(zenithAngleCos))/steepness)));\n}\n\n// Filmic ToneMapping http://filmicgames.com/archives/75\nfloat A = 0.15;\nfloat B = 0.50;\nfloat C = 0.10;\nfloat D = 0.20;\nfloat E = 0.02;\nfloat F = 0.30;\nfloat W = 1000.0;\n\nvec3 Uncharted2Tonemap(vec3 x)\n{\n return ((x*(A*x+C*B)+D*E)/(x*(A*x+B)+D*F))-E/F;\n}\n\nvoid main()\n{\n float sunfade = 1.0-clamp(1.0-exp((sunPosition.y/450000.0)),0.0,1.0);\n\n float reileighCoefficient = reileigh - (1.0* (1.0-sunfade));\n\n vec3 sunDirection = normalize(sunPosition);\n\n float sunE = sunIntensity(dot(sunDirection, up));\n\n // extinction (absorbtion + out scattering)\n // rayleigh coefficients\n\n vec3 betaR = simplifiedRayleigh() * reileighCoefficient;\n\n // mie coefficients\n vec3 betaM = totalMie(lambda, K, turbidity) * mieCoefficient;\n\n // optical length\n // cutoff angle at 90 to avoid singularity in next formula.\n float zenithAngle = acos(max(0.0, dot(up, normalize(vWorldPosition - cameraPos))));\n float sR = rayleighZenithLength / (cos(zenithAngle) + 0.15 * pow(93.885 - ((zenithAngle * 180.0) / pi), -1.253));\n float sM = mieZenithLength / (cos(zenithAngle) + 0.15 * pow(93.885 - ((zenithAngle * 180.0) / pi), -1.253));\n\n // combined extinction factor\n vec3 Fex = exp(-(betaR * sR + betaM * sM));\n\n // in scattering\n float cosTheta = dot(normalize(vWorldPosition - cameraPos), sunDirection);\n\n float rPhase = rayleighPhase(cosTheta*0.5+0.5);\n vec3 betaRTheta = betaR * rPhase;\n\n float mPhase = hgPhase(cosTheta, mieDirectionalG);\n vec3 betaMTheta = betaM * mPhase;\n\n vec3 Lin = pow(sunE * ((betaRTheta + betaMTheta) / (betaR + betaM)) * (1.0 - Fex),vec3(1.5));\n Lin *= mix(vec3(1.0),pow(sunE * ((betaRTheta + betaMTheta) / (betaR + betaM)) * Fex,vec3(1.0/2.0)),clamp(pow(1.0-dot(up, sunDirection),5.0),0.0,1.0));\n\n //nightsky\n vec3 direction = normalize(vWorldPosition - cameraPos);\n float theta = acos(direction.y); // elevation --> y-axis, [-pi/2, pi/2]\n float phi = atan(direction.z, direction.x); // azimuth --> x-axis [-pi/2, pi/2]\n vec2 uv = vec2(phi, theta) / vec2(2.0*pi, pi) + vec2(0.5, 0.0);\n // vec3 L0 = texture2D(skySampler, uv).rgb+0.1 * Fex;\n vec3 L0 = vec3(0.1) * Fex;\n\n // composition + solar disc\n float sundisk = smoothstep(sunAngularDiameterCos,sunAngularDiameterCos+0.00002,cosTheta);\n L0 += (sunE * 19000.0 * Fex)*sundisk;\n\n vec3 whiteScale = 1.0/Uncharted2Tonemap(vec3(W));\n\n vec3 texColor = (Lin+L0);\n texColor *= 0.04 ;\n texColor += vec3(0.0,0.001,0.0025)*0.3;\n\n float g_fMaxLuminance = 1.0;\n float fLumScaled = 0.1 / luminance;\n float fLumCompressed = (fLumScaled * (1.0 + (fLumScaled / (g_fMaxLuminance * g_fMaxLuminance)))) / (1.0 + fLumScaled);\n\n float ExposureBias = fLumCompressed;\n\n vec3 curr = Uncharted2Tonemap((log2(2.0/pow(luminance,4.0)))*texColor);\n vec3 color = curr*whiteScale;\n\n vec3 retColor = pow(color,vec3(1.0/(1.2+(1.2*sunfade))));\n\n gl_FragColor.rgb = retColor;\n\n gl_FragColor.a = 1.0;\n}\n"},function(n,e){n.exports="varying vec3 vWorldPosition;\n\nvoid main() {\n vec4 worldPosition = modelMatrix * vec4(position, 1.0);\n vWorldPosition = worldPosition.xyz;\n gl_Position = projectionMatrix * modelViewMatrix * vec4(position, 1.0);\n}\n"}]);
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