Shader "Azure[Sky]/Pixel Dynamic Cloud" { Properties { } SubShader { Tags { "Queue"="Background" "RenderType"="Background" "PreviewType"="Skybox" "IgnoreProjector"="True" } Cull [_Azure_CullMode] // Render side Fog{Mode Off} // Don't use fog ZWrite Off // Don't draw to bepth buffer Pass { CGPROGRAM #pragma vertex vert #pragma fragment frag #pragma target 3.0 uniform int _Azure_SunsetColorMode; uniform float _Azure_Pi316, _Azure_Pi14, _Azure_Scattering, _Azure_SunDiskIntensity, _Azure_Pi, _Azure_Exposure, _Azure_NightIntensity, _Azure_LightSpeed, _Azure_SunSize, _Azure_MoonSize, _Azure_MoonBrightRange, _Azure_MoonEmission, _Azure_StarfieldIntensity, _Azure_MilkyWayIntensity, _Azure_Kr, _Azure_Km, _Azure_DynamicCloudLayer1Altitude, _Azure_DynamicCloudLayer1Direction, _Azure_DynamicCloudLayer1Speed, _Azure_DynamicCloudLayer1Density; uniform float3 _Azure_SunDirection, _Azure_MoonDirection, _Azure_Br, _Azure_Bm, _Azure_MieG, _Azure_StarfieldColorBalance; uniform float4 _Azure_RayleighColor, _Azure_MieColor, _Azure_SunDiskColor, _Azure_MoonColor, _Azure_MoonBrightColor, _Azure_DynamicCloudLayer1Color1, _Azure_DynamicCloudLayer1Color2; uniform float4x4 _Azure_SunMatrix, _Azure_MoonMatrix, _Azure_StarMatrix, _Azure_NoiseMatrix, _Azure_RelativeSunMatrix, _Azure_UpMatrix; uniform sampler2D _Azure_SunTexture, _Azure_MoonTexture, _Azure_CloudNoise; uniform samplerCUBE _Azure_StarfieldTexture, _Azure_StarNoiseTexture; struct appdata { float4 vertex : POSITION; }; struct v2f { float4 Position : SV_POSITION; float3 WorldPos : TEXCOORD0; float3 SunPos : TEXCOORD1; float3 MoonPos : TEXCOORD2; float3 StarPos : TEXCOORD3; float3 NoiseRot : TEXCOORD4; float3 CloudPos : TEXCOORD5; float4 CloudUV : TEXCOORD6; }; v2f vert (appdata v) { v2f Output; UNITY_INITIALIZE_OUTPUT(v2f, Output); Output.Position = UnityObjectToClipPos(v.vertex); Output.WorldPos = normalize(mul((float3x3)unity_WorldToObject, v.vertex.xyz)); Output.WorldPos = normalize(mul((float3x3)_Azure_UpMatrix, Output.WorldPos)); //Dynamic Clouds. //-------------------------------- //Position. Output.CloudPos = normalize(mul((float3x3)unity_WorldToObject, v.vertex.xyz)); Output.CloudPos = normalize(mul((float3x3)_Azure_UpMatrix, Output.CloudPos)); //Direction. float s = sin (_Azure_DynamicCloudLayer1Direction); float c = cos (_Azure_DynamicCloudLayer1Direction); float2x2 rotationMatrix = float2x2( c, -s, s, c); Output.CloudPos.y *= _Azure_DynamicCloudLayer1Altitude; //float3 viewDir = normalize(Output.WorldPos + float3(0.0, 1.0, 0.0)); //Output.CloudPos.y *= dot(float3(0.0, viewDir.y + 50.0, 0), float3(0.0, -0.15, 0.0)) * -1.0; Output.CloudPos.xz = mul(Output.CloudPos.xz, rotationMatrix ); //Uv. float cloudSpeed = _Azure_DynamicCloudLayer1Speed * _Time; Output.CloudPos = normalize(Output.CloudPos); Output.CloudUV.xy = Output.CloudPos.xz * 0.25 - 0.005 + float2(cloudSpeed/20, cloudSpeed); Output.CloudUV.zw = Output.CloudPos.xz * 0.35 -0.0065 + float2(cloudSpeed/20, cloudSpeed); //Matrix. //-------------------------------- Output.SunPos = mul((float3x3)_Azure_SunMatrix, v.vertex.xyz) * _Azure_SunSize; Output.StarPos = mul((float3x3)_Azure_RelativeSunMatrix, Output.WorldPos); Output.StarPos = mul((float3x3)_Azure_StarMatrix, Output.StarPos); Output.NoiseRot = mul((float3x3)_Azure_NoiseMatrix, v.vertex.xyz); Output.MoonPos = mul((float3x3)_Azure_MoonMatrix, v.vertex.xyz) * 0.75 * _Azure_MoonSize; Output.MoonPos.x *= -1.0; return Output; } bool iSphere(in float3 origin, in float3 direction, in float3 position, in float radius, out float3 normalDirection) { float3 rc = origin - position; float c = dot(rc, rc) - (radius * radius); float b = dot(direction, rc); float d = b * b - c; float t = -b - sqrt(abs(d)); float st = step(0.0, min(t, d)); normalDirection = normalize(-position + (origin + direction * t)); if (st > 0.0) { return true; } return false; } float4 frag (v2f IN) : SV_Target { //Initializations. //-------------------------------- float3 inScatter = float3(0.0, 0.0, 0.0); float3 nightSky = float3(0.0, 0.0, 0.0); float3 fex = float3(0.0, 0.0, 0.0); float r = length(float3(0.0, _Azure_LightSpeed, 0.0)); //Directions. //-------------------------------- float3 viewDir = normalize(IN.WorldPos); float sunCosTheta = dot(viewDir, _Azure_SunDirection); float moonCosTheta = saturate(dot(viewDir, _Azure_MoonDirection)); float sunRise = saturate(dot(float3(0.0, 500.0, 0.0), _Azure_SunDirection) / r); if(_Azure_SunsetColorMode == 0) { //Optical Depth. //-------------------------------- float zenith = acos(saturate(dot(float3(0.0, 1.0, 0.0), viewDir))); float z = cos(zenith) + 0.15 * pow(93.885 - ((zenith * 180.0) / _Azure_Pi), -1.253); float SR = _Azure_Kr / z; float SM = _Azure_Km / z; //Total Extinction. //-------------------------------- fex = exp(-(_Azure_Br*SR + _Azure_Bm*SM)); float sunset = clamp(dot(float3(0.0, 1.0, 0.0), _Azure_SunDirection), 0.0, 0.5); float3 extinction = lerp(fex, (1.0 - fex), sunset); //Scattering. //-------------------------------- //float rayPhase = 1.0 + pow(sunCosTheta, 2.0); //Preetham rayleigh phase function. float rayPhase = 2.0 + 0.5 * pow(sunCosTheta, 2.0); //Rayleigh phase function based on the Nielsen's paper. float miePhase = _Azure_MieG.x / pow(_Azure_MieG.y - _Azure_MieG.z * sunCosTheta, 1.5); //The Henyey-Greenstein phase function. float3 BrTheta = _Azure_Pi316 * _Azure_Br * rayPhase * _Azure_RayleighColor.rgb * extinction; float3 BmTheta = _Azure_Pi14 * _Azure_Bm * miePhase * _Azure_MieColor.rgb * extinction * sunRise; float3 BrmTheta = (BrTheta + BmTheta) / (_Azure_Br + _Azure_Bm); inScatter = BrmTheta * _Azure_Scattering * (1.0 - fex); inScatter *= sunRise; //Night Sky. //-------------------------------- BrTheta = _Azure_Pi316 * _Azure_Br * rayPhase * _Azure_RayleighColor.rgb; BrmTheta = (BrTheta) / (_Azure_Br + _Azure_Bm); nightSky = BrmTheta * _Azure_NightIntensity * (1.0 - fex); } else { //Optical Depth //-------------------------------- float zenith = acos(length(viewDir.y)); //float zenith = acos(saturate(dot(float3(0.0, 1.0, 0.0), viewDir))); float z = cos(zenith) + 0.15 * pow(93.885 - ((zenith * 180.0) / _Azure_Pi), -1.253); float SR = _Azure_Kr / z; float SM = _Azure_Km / z; //Total Extinction. //-------------------------------- fex = exp(-(_Azure_Br*SR + _Azure_Bm*SM)); //Scattering. //-------------------------------- float rayPhase = 2.0 + 0.5 * pow(sunCosTheta, 2.0); float miePhase = _Azure_MieG.x / pow(_Azure_MieG.y - _Azure_MieG.z * sunCosTheta, 1.5); float3 BrTheta = _Azure_Pi316 * _Azure_Br * rayPhase * _Azure_RayleighColor.rgb; float3 BmTheta = _Azure_Pi14 * _Azure_Bm * miePhase * _Azure_MieColor.rgb * sunRise; float3 BrmTheta = (BrTheta + BmTheta) / (_Azure_Br + _Azure_Bm); inScatter = BrmTheta * _Azure_Scattering * (1.0 - fex); inScatter *= sunRise; //inScatter *= pow(max(0.5, viewDir.y + 0.5), 2.0); //Night Sky. //-------------------------------- nightSky = (1.0 - fex) * _Azure_RayleighColor.rgb * _Azure_NightIntensity; BrmTheta = (BrTheta) / (_Azure_Br + _Azure_Bm); nightSky = BrmTheta * _Azure_NightIntensity * (1.0 - fex); } float horizonExtinction = saturate((viewDir.y) * 1000.0) * fex.b; //Dynamic Clouds Layer1. //-------------------------------- float4 tex1 = tex2D(_Azure_CloudNoise, IN.CloudUV.xy ); float4 tex2 = tex2D(_Azure_CloudNoise, IN.CloudUV.zw ); float3 cloud = float3(0.0, 0.0, 0.0); float cloudAlpha = 1.0; float noise1 = 1.0; float noise2 = 1.0; float mixCloud = 0.0; if(_Azure_DynamicCloudLayer1Density<25) { #ifndef UNITY_COLORSPACE_GAMMA _Azure_DynamicCloudLayer1Color1 = pow(_Azure_DynamicCloudLayer1Color1, 2.2); _Azure_DynamicCloudLayer1Color2 = pow(_Azure_DynamicCloudLayer1Color2, 2.2); #endif noise1 = pow(tex1.g + tex2.g, 0.1); noise2 = pow(tex2.b * tex1.r, 0.25); cloudAlpha = saturate(pow(noise1 * noise2, _Azure_DynamicCloudLayer1Density)); float3 cloud1 = lerp(_Azure_DynamicCloudLayer1Color1.rgb, float3(0.0, 0.0, 0.0), noise1); float3 cloud2 = lerp(_Azure_DynamicCloudLayer1Color1.rgb, _Azure_DynamicCloudLayer1Color2.rgb, noise2) * 2.5; cloud = lerp(cloud1, cloud2, noise1 * noise2); cloudAlpha = 1.0 - cloudAlpha; mixCloud = saturate(pow(IN.CloudPos.y, 5.0) * pow(noise1 * noise2, _Azure_DynamicCloudLayer1Density)); } //Sun Disk. //-------------------------------- float3 sunTex = tex2D( _Azure_SunTexture, IN.SunPos + 0.5).rgb * _Azure_SunDiskColor * _Azure_SunDiskIntensity; sunTex = pow(sunTex, 2.0); sunTex *= fex.b * saturate(sunCosTheta) * cloudAlpha; //Moon Sphere. //-------------------------------- float3 rayOrigin = float3(0.0, 0.0, 0.0);//_WorldSpaceCameraPos; float3 rayDirection = viewDir; float3 moonPosition = _Azure_MoonDirection * 38400.0 * _Azure_MoonSize; float3 normalDirection = float3(0.0, 0.0, 0.0); float3 moonColor = float3(0.0, 0.0, 0.0); float4 moonTex = tex2D( _Azure_MoonTexture, IN.MoonPos.xy + 0.5) * moonCosTheta; float moonMask = 1.0 - moonTex.a; if(iSphere(rayOrigin, rayDirection, moonPosition, 17370.0, normalDirection)) { float moonSphere = max(dot(normalDirection, _Azure_SunDirection), 0.0) * moonTex.a * 2.0; moonColor = moonTex.rgb * moonSphere * _Azure_MoonColor.rgb * horizonExtinction; moonColor *= cloudAlpha; } //Moon Bright. //-------------------------------- float moonRise = saturate(dot(float3(0.0, 500.0, 0.0), _Azure_MoonDirection) / r); float bright = 1.0 + dot(viewDir, -_Azure_MoonDirection); float3 moonBright = 1.0 / (1.0 + bright * _Azure_MoonBrightRange) * _Azure_MoonBrightColor.rgb; moonBright += 1.0 / (_Azure_MoonEmission + bright * 200.0) * _Azure_MoonColor.rgb; moonBright = moonBright * moonRise; //Starfield. //-------------------------------- float scintillation = texCUBE(_Azure_StarNoiseTexture, IN.NoiseRot) * 2.0; float4 starTex = texCUBE(_Azure_StarfieldTexture, IN.StarPos); float3 stars = starTex.rgb * starTex.a * scintillation; float3 milkyWay = pow(starTex.rgb, 1.5) * _Azure_MilkyWayIntensity; float3 starfield = (stars + milkyWay) * _Azure_StarfieldColorBalance * moonMask * horizonExtinction * _Azure_StarfieldIntensity; starfield *= cloudAlpha; //Output. //-------------------------------- float3 OutputColor = inScatter + sunTex + nightSky + starfield + moonColor + moonBright; //Tonemapping. OutputColor = saturate(1.0 - exp(-_Azure_Exposure * OutputColor)); //Color Correction. OutputColor = pow(OutputColor, 2.2); #ifdef UNITY_COLORSPACE_GAMMA OutputColor = pow(OutputColor, 0.4545); #else OutputColor = OutputColor; #endif //Apply Clouds. OutputColor = lerp(OutputColor, cloud, mixCloud); return float4(OutputColor, 1.0); } ENDCG } } }