// https://www.shadertoy.com/view/lslSDS ////////////////////////////////////////////////// // Xavier Benech // Galaxy Trip // Inspired by "Star Tunnel" shader from P_Malin // https://www.shadertoy.com/view/MdlXWr // License Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License. // // Increase pass count for a denser effect #define PASS_COUNT 4 float fBrightness = 2.5; // Number of angular segments float fSteps = 121.0; float fParticleSize = 0.015; float fParticleLength = 0.5 / 60.0; // Min and Max star position radius. Min must be present to prevent stars too near camera float fMinDist = 0.8; float fMaxDist = 5.0; float fRepeatMin = 1.0; float fRepeatMax = 2.0; // fog density float fDepthFade = 0.8; float Random(float x) { return fract(sin(x * 123.456) * 23.4567 + sin(x * 345.678) * 45.6789 + sin(x * 456.789) * 56.789); } vec3 GetParticleColour( const in vec3 vParticlePos, const in float fParticleSize, const in vec3 vRayDir ) { vec2 vNormDir = normalize(vRayDir.xy); float d1 = dot(vParticlePos.xy, vNormDir.xy) / length(vRayDir.xy); vec3 vClosest2d = vRayDir * d1; vec3 vClampedPos = vParticlePos; vClampedPos.z = clamp(vClosest2d.z, vParticlePos.z - fParticleLength, vParticlePos.z + fParticleLength); float d = dot(vClampedPos, vRayDir); vec3 vClosestPos = vRayDir * d; vec3 vDeltaPos = vClampedPos - vClosestPos; float fClosestDist = length(vDeltaPos) / fParticleSize; float fShade = clamp(1.0 - fClosestDist, 0.0, 1.0); if (d<3.0) { fClosestDist = max(abs(vDeltaPos.x),abs(vDeltaPos.y)) / fParticleSize; float f = clamp(1.0 - 0.8*fClosestDist, 0.0, 1.0); fShade += f*f*f*f; fShade *= fShade; } fShade = fShade * exp2(-d * fDepthFade) * fBrightness; return vec3(fShade); } vec3 GetParticlePos( const in vec3 vRayDir, const in float fZPos, const in float fSeed ) { float fAngle = atan(vRayDir.x, vRayDir.y); float fAngleFraction = fract(fAngle / (3.14 * 2.0)); float fSegment = floor(fAngleFraction * fSteps + fSeed) + 0.5 - fSeed; float fParticleAngle = fSegment / fSteps * (3.14 * 2.0); float fSegmentPos = fSegment / fSteps; float fRadius = fMinDist + Random(fSegmentPos + fSeed) * (fMaxDist - fMinDist); float tunnelZ = vRayDir.z / length(vRayDir.xy / fRadius); tunnelZ += fZPos; float fRepeat = fRepeatMin + Random(fSegmentPos + 0.1 + fSeed) * (fRepeatMax - fRepeatMin); float fParticleZ = (ceil(tunnelZ / fRepeat) - 0.5) * fRepeat - fZPos; return vec3( sin(fParticleAngle) * fRadius, cos(fParticleAngle) * fRadius, fParticleZ ); } vec3 Starfield( const in vec3 vRayDir, const in float fZPos, const in float fSeed ) { vec3 vParticlePos = GetParticlePos(vRayDir, fZPos, fSeed); return GetParticleColour(vParticlePos, fParticleSize, vRayDir); } vec3 RotateX( const in vec3 vPos, const in float fAngle ) { float s = sin(fAngle); float c = cos(fAngle); return vec3( vPos.x, c * vPos.y + s * vPos.z, -s * vPos.y + c * vPos.z); } vec3 RotateY( const in vec3 vPos, const in float fAngle ) { float s = sin(fAngle); float c = cos(fAngle); return vec3( c * vPos.x + s * vPos.z, vPos.y, -s * vPos.x + c * vPos.z); } vec3 RotateZ( const in vec3 vPos, const in float fAngle ) { float s = sin(fAngle); float c = cos(fAngle); return vec3( c * vPos.x + s * vPos.y, -s * vPos.x + c * vPos.y, vPos.z); } // Simplex Noise by IQ vec2 hash( vec2 p ) { p = vec2( dot(p,vec2(127.1,311.7)), dot(p,vec2(269.5,183.3)) ); return -1.0 + 2.0*fract(sin(p)*43758.5453123); } float noise( in vec2 p ) { const float K1 = 0.366025404; // (sqrt(3)-1)/2; const float K2 = 0.211324865; // (3-sqrt(3))/6; vec2 i = floor( p + (p.x+p.y)*K1 ); vec2 a = p - i + (i.x+i.y)*K2; vec2 o = (a.x>a.y) ? vec2(1.0,0.0) : vec2(0.0,1.0); //vec2 of = 0.5 + 0.5*vec2(sign(a.x-a.y), sign(a.y-a.x)); vec2 b = a - o + K2; vec2 c = a - 1.0 + 2.0*K2; vec3 h = max( 0.5-vec3(dot(a,a), dot(b,b), dot(c,c) ), 0.0 ); vec3 n = h*h*h*h*vec3( dot(a,hash(i+0.0)), dot(b,hash(i+o)), dot(c,hash(i+1.0))); return dot( n, vec3(70.0) ); } const mat2 m = mat2( 0.80, 0.60, -0.60, 0.80 ); float fbm4( in vec2 p ) { float f = 0.0; f += 0.5000*noise( p ); p = m*p*2.02; f += 0.2500*noise( p ); p = m*p*2.03; f += 0.1250*noise( p ); p = m*p*2.01; f += 0.0625*noise( p ); return f; } float marble(in vec2 p) { return cos(p.x+fbm4(p)); } float dowarp ( in vec2 q, out vec2 a, out vec2 b ) { float ang=0.; ang = 1.2345 * sin (33.33); //0.015*iTime); mat2 m1 = mat2(cos(ang), -sin(ang), sin(ang), cos(ang)); ang = 0.2345 * sin (66.66); //0.021*iTime); mat2 m2 = mat2(cos(ang), -sin(ang), sin(ang), cos(ang)); a = vec2( marble(m1*q), marble(m2*q+vec2(1.12,0.654)) ); ang = 0.543 * cos (13.33); //0.011*iTime); m1 = mat2(cos(ang), -sin(ang), sin(ang), cos(ang)); ang = 1.128 * cos (53.33); //0.018*iTime); m2 = mat2(cos(ang), -sin(ang), sin(ang), cos(ang)); b = vec2( marble( m2*(q + a)), marble( m1*(q + a) ) ); return marble( q + b +vec2(0.32,1.654)); } // ----------------------------------------------- void mainImage( out vec4 fragColor, in vec2 fragCoord ) { vec2 uv = fragCoord.xy / iResolution.xy; vec2 q = 2.*uv-1.; q.y *= iResolution.y/iResolution.x; // camera vec3 rd = normalize(vec3( q.x, q.y, 1. )); vec3 euler = vec3( sin(iTime * 0.2) * 0.625, cos(iTime * 0.1) * 0.625, iTime * 0.1 + sin(iTime * 0.3) * 0.5); if(iMouse.z > 0.0) { euler.x = -((iMouse.y / iResolution.y) * 2.0 - 1.0); euler.y = -((iMouse.x / iResolution.x) * 2.0 - 1.0); euler.z = 0.0; } rd = RotateX(rd, euler.x); rd = RotateY(rd, euler.y); rd = RotateZ(rd, euler.z); // Nebulae Background float pi = 3.141592654; q.x = 0.5 + atan(rd.z, rd.x)/(2.*pi); q.y = 0.5 - asin(rd.y)/pi + 0.512 + 0.001*iTime; q *= 2.34; vec2 wa = vec2(0.); vec2 wb = vec2(0.); float f = dowarp(q, wa, wb); f = 0.5+0.5*f; vec3 col = vec3(f); float wc = 0.; wc = f; col = vec3(wc, wc*wc, wc*wc*wc); wc = abs(wa.x); col -= vec3(wc*wc, wc, wc*wc*wc); wc = abs(wb.x); col += vec3(wc*wc*wc, wc*wc, wc); col *= 0.7; col.x = pow(col.x, 2.18); col.z = pow(col.z, 1.88); col = smoothstep(0., 1., col); col = 0.5 - (1.4*col-0.7)*(1.4*col-0.7); col = 0.75*sqrt(col); col *= 1. - 0.5*fbm4(8.*q); col = clamp(col, 0., 1.); // StarField float fShade = 0.0; float a = 0.2; float b = 10.0; float c = 1.0; float fZPos = 5.0;// + iTime * c + sin(iTime * a) * b; float fSpeed = 0.; //c + a * b * cos(a * iTime); fParticleLength = 0.25 * fSpeed / 60.0; float fSeed = 0.0; vec3 vResult = vec3(0.); vec3 red = vec3(0.7,0.4,0.3); vec3 blue = vec3(0.3,0.4,0.7); vec3 tint = vec3(0.); float ti = 1./float(PASS_COUNT-1); float t = 0.; for(int i=0; i