// "Tempting the Mariner" by dr2 - 2017 // License: Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License float PrBoxDf (vec3 p, vec3 b); float PrBox2Df (vec2 p, vec2 b); float PrCapsDf (vec3 p, float r, float h); float PrEVCapsDf (vec3 p, vec4 u, float r); float PrEECapsDf (vec3 p, vec3 v1, vec3 v2, float r); float PrCylDf (vec3 p, float r, float h); float PrSphDf (vec3 p, float r); float PrFlatCylDf (vec3 p, float rhi, float rlo, float h); float PrTorusDf (vec3 p, float ri, float rc); float SmoothMin (float a, float b, float r); float SmoothBump (float lo, float hi, float w, float x); vec2 Rot2D (vec2 q, float a); float Noisefv2 (vec2 p); float Fbm2 (vec2 p); mat3 birdMat[2], bdMat; vec4 vum[4], vur[5]; vec3 vim[4], vir[5]; vec3 birdPos[2], bdPos, fltBox, shipConf, bDeck, qHit, sunDir, cloudDisp; float tCur, dstFar, szFac, shipRot, birdVel, birdLen, legAng, htWat; int idObj, idObjGrp; bool isRefl; const int idHull = 1, idRud = 2, idStruc = 3, idMast = 4, idSparT = 5, idSparL = 6, idSailT = 7, idSailA = 8, idSailF = 9, idFlag = 10, idRig = 11, idWing = 21, idBdy = 22, idEye = 23, idBk = 24, idLeg = 25; const float pi = 3.14159; float WaveHt (vec2 p) { mat2 qRot = mat2 (0.8, -0.6, 0.6, 0.8); vec4 t4, v4; vec2 q, t, tw; float wFreq, wAmp, h; q = 0.5 * p + vec2 (0., tCur); h = 0.2 * sin (q.y) + 0.15 * sin (dot (q, vec2 (0.1, 1.2))) + 0.1 * sin (dot (q, vec2 (-0.2, 1.4))); h *= 0.3 * (1. - smoothstep (0.8 * dstFar, dstFar, length (p))); q = p; wFreq = 0.5; wAmp = 0.05; tw = 0.5 * tCur * vec2 (1., -1.); for (int j = 0; j < 4; j ++) { q *= qRot; t4 = q.xyxy * wFreq + tw.xxyy; t = vec2 (Noisefv2 (t4.xy), Noisefv2 (t4.zw)); t4 += 2. * t.xxyy - 1.; v4 = (1. - abs (sin (t4))) * (abs (sin (t4)) + abs (cos (t4))); t = 1. - sqrt (v4.xz * v4.yw); t *= t; h += wAmp * dot (t, t); wFreq *= 2.; wAmp *= 0.5; } return h; } vec3 WaveNf (vec2 p, float d) { vec2 e = vec2 (max (0.01, 0.001 * d * d), 0.); return normalize (vec3 (WaveHt (p) - vec2 (WaveHt (p + e.xy), WaveHt (p + e.yx)), e.x).xzy); } vec3 SkyCol (vec3 ro, vec3 rd) { vec3 col, skyCol, p; float ds, fd, att, attSum, d, sd; p = ro + rd * (200. - ro.y) / rd.y; ds = 0.1 * sqrt (length (ro - p)); fd = 0.001 / (smoothstep (0., 10., ds) + 0.1); p.xz *= fd; p.xz -= cloudDisp.xz; p *= 3.; att = Fbm2 (p.xz); attSum = att; fd *= 3.; d = fd; ds *= fd; for (int j = 0; j < 4; j ++) { attSum += Fbm2 (p.xz + d * sunDir.xz); d += ds; } sd = clamp (dot (sunDir, rd), 0., 1.); skyCol = mix (vec3 (0.7, 1., 1.), vec3 (1., 0.4, 0.1), 0.25 + 0.75 * sd); col = mix (vec3 (0.5, 0.75, 1.), skyCol, exp (-2. * (3. - sd) * max (rd.y - 0.1, 0.))) + 0.3 * (vec3 (1., 0.4, 0.2) * pow (sd, 256.) + vec3 (1., 0.8, 0.7) * pow (sd, 1024.)); attSum = 1. - smoothstep (1., 9., attSum); col = mix (vec3 (0.4, 0., 0.2), mix (col, vec3 (0.2), att * (0.001 + 0.999 * smoothstep (0.001, 0.004, rd.y))), attSum) + vec3 (1., 0.4, 0.) * pow (attSum * att, 4.) * (pow (sd, 8.) + 0.5); return col; } #define DMINQ(id) if (d < dMin) { dMin = d; idObj = id; qHit = q; } float ShipHullDf (vec3 p, float dMin) { vec3 q; float d, fy, fz, gz; q = p; d = abs (p.z) - 4.5; q.z = mod (q.z + 1.4, 2.8) - 1.4; q.yz -= vec2 (-3.4, -0.4); d = max (d, PrBoxDf (q, vec3 (0.3, 0.1, 0.5))); DMINQ (idStruc); q = p; q.x = abs (q.x); q.yz -= vec2 (-3.8, 0.5); fz = q.z / 5. + 0.3; fz *= fz; fy = 1. - smoothstep (-1.3, -0.1, q.y); gz = smoothstep (2., 5., q.z); bDeck = vec3 ((1. - 0.45 * fz * fz) * (1.1 - 0.5 * fy * fy) * (1. - 0.5 * smoothstep (-5., -2., q.y) * smoothstep (2., 5., q.z)), 0.78 - 0.8 * gz * gz - 0.2 * (1. - smoothstep (-5.2, -4., q.z)), 5. * (1. + 0. * 0.02 * q.y)); d = min (PrBoxDf (vec3 (q.x, q.y + bDeck.y - 0.6, q.z), bDeck), max (PrBoxDf (q - vec3 (0., 0.72, -4.6), vec3 (bDeck.x, 0.12, 0.4)), - PrBox2Df (vec2 (abs (q.x) - 0.4, q.y - 0.65), vec2 (0.2, 0.08)))); d = max (d, - PrBoxDf (vec3 (q.x, q.y - 0.58 - 0.1 * fz, q.z), vec3 (bDeck.x - 0.07, 0.3, bDeck.z - 0.1))); q = p; d = max (d, - max (PrBox2Df (vec2 (q.y + 3.35, mod (q.z + 0.25, 0.5) - 0.25), vec2 (0.08, 0.1)), abs (q.z + 0.5) - 3.75)); DMINQ (idHull); q = p; d = PrBoxDf (q + vec3 (0., 4.4, 4.05), vec3 (0.03, 0.35, 0.5)); DMINQ (idRud); return dMin; } float ShipMastDf (vec3 p, float dMin) { vec3 q, qq; float d, fy, fz, s, rSpar, yLim, zLim; rSpar = 0.05; fy = 1. - 0.07 * p.y; fz = 1. - 0.14 * step (1., abs (p.z)); zLim = abs (p.z) - 4.5; q = p; d = zLim; q.z = mod (q.z + 1.4, 2.8) - 1.2; d = max (d, PrCapsDf ((q - vec3 (0., 3.7 * (fz - 1.), 0.)).xzy, 0.1 * fy, 3.7 * fz)); DMINQ (idMast); q = p; yLim = abs (q.y - 0.2 * fz) - 3. * fz; qq = q; qq.y = mod (qq.y - 3.3 * (fz - 1.), 2. * fz) - fz; qq.z = mod (qq.z + 1.4, 2.8) - 1.4 + 0.1 * fz; d = max (max (min (d, PrCylDf (vec3 (qq - vec3 (0., 0.05 * fy * fz, 0.1 * fz - 0.23)).xzy, 0.15 * fy, 0.11 * fy * fz)), yLim), zLim); DMINQ (idMast); d = max (max (PrCapsDf (qq.yzx, 0.05, 1.23 * fy * fz), yLim), zLim); DMINQ (idSparT); q = p; d = min (d, min (PrEVCapsDf (q - vim[0], vum[0], rSpar), PrEVCapsDf (q - vim[1], vum[1], rSpar))); d = min (d, min (PrEVCapsDf (q - vim[2], vum[2], rSpar), PrEVCapsDf (q - vim[3], vum[3], rSpar))); DMINQ (idSparL); return dMin; } float ShipSailDf (vec3 p, float dMin) { vec3 q, qq, w; float d, fy, fz; fy = 1. - 0.07 * p.y; fz = 1. - 0.14 * step (1., abs (p.z)); q = p; qq = q; qq.y = mod (qq.y - 3.1 * (fz - 1.), 2. * fz) - fz; qq.z = mod (qq.z + 1.4, 2.8) - 1.4 + 0.2 * (fz - abs (qq.y)) * (fz - abs (qq.y)) - 0.1 * fz; d = max (max (max (PrBoxDf (qq, vec3 ((1.2 - 0.07 * q.y) * fz, fz, 0.01)), min (qq.y, 1.5 * fy * fz - length (vec2 (qq.x, qq.y + 0.9 * fy * fz)))), abs (q.y - 3. * (fz - 1.)) - 2.95 * fz), - PrBox2Df (qq.yz, vec2 (0.01 * fz))); d = max (d, abs (p.z) - 4.5); DMINQ (idSailT); q = p; q.z -= -3.8; q.y -= -1.75 - 0.2 * q.z; d = PrBoxDf (q, vec3 (0.01, 0.9 - 0.2 * q.z, 0.6)); DMINQ (idSailA); q = p; q.yz -= vec2 (-1., 4.5); w = vec3 (1., q.yz); d = max (max (max (abs (q.x) - 0.01, - dot (w, vec3 (2.3, 1., -0.35))), - dot (w, vec3 (0.68, -0.74, -1.))), - dot (w, vec3 (0.41, 0.4, 1.))); DMINQ (idSailF); q = p; q.yz -= vec2 (3.4, 0.18); d = PrBoxDf (q, vec3 (0.01, 0.2, 0.3)); DMINQ (idFlag); return dMin; } float ShipRigDf (vec3 p, float dMin) { vec3 q; float rRig, d, fz, gz, s; rRig = 0.02; fz = 1. - 0.14 * step (1., abs (p.z)); q = p; d = abs (p.z) - 4.5; gz = (q.z - 0.5) / 5. + 0.3; gz *= gz; gz = 1.05 * (1. - 0.45 * gz * gz); q.x = abs (q.x); q.z = mod (q.z + 1.4, 2.8) - 1.4; d = max (d, min (PrEECapsDf (q, vec3 (1.05 * gz, -3.25, -0.5), vec3 (1.4 * fz, -2.95, -0.05), 0.7 * rRig), PrEECapsDf (vec3 (q.xy, abs (q.z + 0.2) - 0.01 * (0.3 - 2. * q.y)), vec3 (gz, -3.2, 0.), vec3 (0.05, -0.9 + 2. * (fz - 1.), 0.), rRig))); q = p; d = min (d, PrEVCapsDf (q - vir[0], vur[0], 0.8 * rRig)); d = min (min (d, min (PrEVCapsDf (q - vir[1], vur[1], rRig), PrEVCapsDf (q - vir[2], vur[2], rRig))), PrEVCapsDf (q - vir[3], vur[3], rRig)); q.x = abs (q.x); d = min (d, PrEVCapsDf (q - vir[4], vur[4], rRig)); s = step (1.8, q.y) - step (q.y, -0.2); d = min (min (d, min (PrEECapsDf (q, vec3 (0.95, 0.4, 2.7) + vec3 (-0.1, 1.7, 0.) * s, vec3 (0.05, 1.1, -0.15) + vec3 (0., 2., 0.) * s, rRig), PrEECapsDf (q, vec3 (1.05, 1., -0.1) + vec3 (-0.1, 2., 0.) * s, vec3 (0.05, 0.5, -2.95) + vec3 (0., 1.7, 0.) * s, rRig))), PrEECapsDf (q, vec3 (0.95, 0.4, -2.9) + vec3 (-0.1, 1.7, 0.) * s, vec3 (0.05, 0.9, -0.25) + vec3 (0., 2., 0.) * s, rRig)); DMINQ (idRig); return dMin; } float BdBodyDf (vec3 p, float dMin) { vec3 q; float bkLen, d, a, wr, tr, u; bkLen = 0.15 * birdLen; q = p; wr = q.z / birdLen; if (wr > 0.5) { u = (wr - 0.5) / 0.5; tr = 0.17 - 0.11 * u * u; } else { u = clamp ((wr - 0.5) / 1.5, -1., 1.); u *= u; tr = 0.17 - u * (0.34 - 0.18 * u); } d = PrCapsDf (q, tr * birdLen, birdLen); DMINQ (idObjGrp + idBdy); q = p; q.x = abs (q.x); wr = (wr + 1.) * (wr + 1.); q -= birdLen * vec3 (0.3 * wr, 0.1 * wr, -1.2); d = PrCylDf (q, 0.009 * birdLen, 0.2 * birdLen); DMINQ (idObjGrp + idBdy); q = p; q.x = abs (q.x); q -= birdLen * vec3 (0.08, 0.05, 0.9); d = PrSphDf (q, 0.04 * birdLen); DMINQ (idObjGrp + idEye); q = p; q -= birdLen * vec3 (0., -0.015, 1.15); wr = clamp (0.5 - 0.3 * q.z / bkLen, 0., 1.); d = PrFlatCylDf (q, 0.25 * wr * bkLen, 0.25 * wr * bkLen, bkLen); DMINQ (idObjGrp + idBk); return dMin; } float BdWingDf (vec3 p, float dMin) { vec3 q, qh; float wngFreq, wSegLen, wChord, wSpar, fTap, tFac, d, dd, a, wr, wf; wngFreq = 6.; wSegLen = 0.15 * birdLen; wChord = 0.3 * birdLen; wSpar = 0.03 * birdLen; fTap = 8.; tFac = (1. - 1. / fTap); q = p - vec3 (0., 0., 0.3 * birdLen); q.x = abs (q.x) - 0.1 * birdLen; wf = 1.; a = -0.1 + 0.2 * sin (wngFreq * tCur); d = dMin; qh = q; for (int k = 0; k < 5; k ++) { q.xy = Rot2D (q.xy, a); q.x -= wSegLen; wr = wf * (1. - 0.5 * q.x / (fTap * wSegLen)); dd = PrFlatCylDf (q.zyx, wr * wChord, wr * wSpar, wSegLen); if (k < 4) { q.x -= wSegLen; dd = min (dd, PrCapsDf (q, wr * wSpar, wr * wChord)); } else { q.x += wSegLen; dd = max (dd, PrCylDf (q.xzy, wr * wChord, wSpar)); dd = min (dd, max (PrTorusDf (q.xzy, 0.98 * wr * wSpar, wr * wChord), - q.x)); } if (dd < d) { d = dd; qh = q; } a *= 1.03; wf *= tFac; } q = qh; DMINQ (idObjGrp + idWing); return dMin; } float BdFootDf (vec3 p, float dMin) { vec3 q; float lgLen, ftLen, d; lgLen = 0.1 * birdLen; ftLen = 0.5 * lgLen; q = p; q.x = abs (q.x); q -= birdLen * vec3 (0.1, -0.12, 0.6); q.yz = Rot2D (q.yz, legAng); q.xz = Rot2D (q.xz, -0.05 * pi); q.z += lgLen; d = PrCylDf (q, 0.15 * lgLen, lgLen); DMINQ (idObjGrp + idLeg); q.z += lgLen; q.xy = Rot2D (q.xy, 0.5 * pi); q.xy = Rot2D (q.xy, floor (3. * atan (q.y, - q.x) / (2. * pi) + 0.5) * (2. * pi / 3.)); q.xz = Rot2D (q.xz, - pi + 0.4 * legAng); q.z -= ftLen; d = PrCapsDf (q, 0.2 * ftLen, ftLen); DMINQ (idObjGrp + idLeg); return dMin; } float ObjDf (vec3 p) { vec3 q; float dMin; dMin = dstFar; q = p; q.xz = Rot2D (q.xz, shipRot); q.y -= shipConf.x + 6.6 * szFac; q /= szFac; dMin = dstFar / szFac; dMin = ShipHullDf (q, dMin); dMin = ShipMastDf (q, dMin); dMin = ShipSailDf (q, dMin); if (! isRefl) dMin = ShipRigDf (q, dMin); dMin *= 0.7 * szFac; dMin = max (dMin, - p.y + htWat); idObjGrp = 1 * 256; q = birdMat[0] * (p - birdPos[0]); dMin /= 0.9; dMin = BdBodyDf (q, dMin); dMin = BdWingDf (q, dMin); dMin = BdFootDf (q, dMin); idObjGrp = 2 * 256; q = birdMat[1] * (p - birdPos[1]); dMin = BdBodyDf (q, dMin); dMin = BdWingDf (q, dMin); dMin = BdFootDf (q, dMin); return 0.9 * dMin; } float ObjRay (vec3 ro, vec3 rd) { float dHit, d; dHit = 0.; for (int j = 0; j < 150; j ++) { d = ObjDf (ro + rd * dHit); dHit += d; if (d < 0.0005 || dHit > dstFar) break; } return dHit; } vec3 ObjNf (vec3 p) { vec4 v; vec2 e = vec2 (0.0005, -0.0005); v = vec4 (ObjDf (p + e.xxx), ObjDf (p + e.xyy), ObjDf (p + e.yxy), ObjDf (p + e.yyx)); return normalize (vec3 (v.x - v.y - v.z - v.w) + 2. * v.yzw); } vec4 ShipCol () { vec4 col4; vec2 cg; if (idObj == idHull) { if (abs (qHit.x) < bDeck.x - 0.08 && qHit.y > -3.6 && qHit.z > - bDeck.z + 0.62) { col4 = vec4 (0.5, 0.3, 0., 0.1) * (0.5 + 0.5 * SmoothBump (0.05, 0.95, 0.02, mod (8. * qHit.x, 1.))); } else if (qHit.y > -4.) { col4 = vec4 (0.7, 0.5, 0.1, 0.1); if (abs (qHit.z - 4.) < 0.25 && abs (qHit.y + 3.55) < 0.05) col4 *= 1.2; else if (qHit.z < -4. && abs (qHit.x) < 0.84 && abs (qHit.y + 3.62) < 0.125) { cg = step (0.1, abs (fract (vec2 (6. * qHit.x, 8. * (qHit.y + 3.62)) + 0.5) - 0.5)); if (cg.x * cg.y == 1.) col4 = vec4 (0.8, 0.8, 0.2, -1.); else col4 *= 0.8; } else { col4 *= 0.7 + 0.3 * SmoothBump (0.05, 0.95, 0.02, mod (8. * qHit.y, 1.)); } } else if (qHit.y > -4.05) { col4 = vec4 (0.8, 0.8, 0.8, 0.1); } else { col4 = vec4 (0.3, 0.2, 0.1, 0.); } } else if (idObj == idRud) { col4 = vec4 (0.5, 0.3, 0., 0.); } else if (idObj == idStruc) { col4 = vec4 (0.4, 0.3, 0.1, 0.1); if (max (abs (qHit.x), abs (qHit.z + 0.22)) < 0.2) { cg = step (0.1, abs (fract (vec2 (10. * vec2 (qHit.x, qHit.z + 0.22)) + 0.5) - 0.5)); if (cg.x * cg.y == 1.) col4 = vec4 (0.8, 0.8, 0.2, -1.); } } else if (idObj == idSailT) { qHit.x *= (1. + 0.07 * qHit.y) * (1. + 0.14 * step (1., abs (qHit.z))); col4 = vec4 (1., 1., 1., 0.) * (0.7 + 0.3 * SmoothBump (0.05, 0.95, 0.02, mod (4. * qHit.x, 1.))); if (abs (qHit.z) < 0.2 && abs (abs (length (qHit.xy - vec2 (0., 0.3)) - 0.35) - 0.15) < 0.07) col4 *= vec4 (1., 0.2, 0.2, 1.); } else if (idObj == idSailA) { col4 = vec4 (1., 1., 1., 0.) * (0.7 + 0.3 * SmoothBump (0.05, 0.95, 0.02, mod (5. * qHit.z, 1.))); } else if (idObj == idSailF) { col4 = vec4 (1., 1., 1., 0.) * (0.7 + 0.3 * SmoothBump (0.05, 0.95, 0.02, mod (2.95 * qHit.y + 4. * qHit.z - 0.5, 1.))); } else if (idObj == idFlag) { col4 = vec4 (1., 1., 0.5, 0.1); if (abs (abs (length (qHit.yz) - 0.1) - 0.04) < 0.02) col4 *= vec4 (1., 0.2, 0.2, 1.); } else if (idObj == idMast) { col4 = vec4 (0.7, 0.4, 0., 0.1); if (length (qHit.xz) < 0.16 * (1. - 0.07 * qHit.y)) col4 *= 0.6 + 0.4 * SmoothBump (0.03, 0.97, 0.01, mod (2. * qHit.y / (1. + 0.14 * step (1., abs (qHit.z))), 1.)); if (qHit.y > 3.65) col4 = vec4 (1., 0., 0., -1.); } else if (idObj == idSparT) { qHit.x *= (1. + 0.07 * qHit.y) * (1. + 0.14 * step (1., abs (qHit.z))); col4 = vec4 (0.7, 0.4, 0., 0.1) * (0.6 + 0.4 * SmoothBump (0.08, 0.92, 0.01, mod (4. * qHit.x, 1.))); } else if (idObj == idSparL) { col4 = vec4 (0.7, 0.4, 0., 0.1); if (qHit.z > 6.65) col4 = vec4 (1., 1., 0.3, -1.); } else if (idObj == idRig) { col4 = vec4 (0.2, 0.15, 0.1, 0.); } return col4; } vec4 BirdCol (vec3 n) { vec4 col4; vec3 nn; float gw, w; int ig, id; ig = idObj / 256; id = idObj - 256 * ig; if (id == idWing) { gw = 0.15 * birdLen; w = mod (qHit.x, gw); w = SmoothBump (0.15 * gw, 0.65 * gw, 0.1 * gw, w); col4 = vec4 (mix (vec3 (0.05), vec3 (1.), w), 0.1); } else if (id == idEye) { col4 = vec4 (0., 0.6, 0., 1.); } else if (id == idBdy) { if (ig == 1) nn = birdMat[0] * n; else nn = birdMat[1] * n; col4 = vec4 (mix (mix (vec3 (1.), vec3 (0.1), smoothstep (0.5, 1., nn.y)), vec3 (1.), 1. - smoothstep (-1., -0.7, nn.y)), 0.1); } else if (id == idBk) { col4 = vec4 (1., 1., 0., 0.1); } else if (id == idLeg) { col4 = vec4 ((0.5 + 0.4 * sin (100. * qHit.z)) * vec3 (0.6, 0.4, 0.), 0.1); } return col4; } void EvalShipConf () { vec3 vd; shipConf = vec3 (-4. * szFac, 0., 0.); shipRot = 0.25 * pi * cos (0.02 * pi * tCur); vim[0] = vec3 (0., -3.5, 4.3); vd = vec3 (0., -2.6, 6.7) - vim[0]; vum[0] = vec4 (normalize (vd), length (vd)); vim[1] = vec3 (0., -4., 4.1); vd = vec3 (0., -2.9, 6.) - vim[1]; vum[1] = vec4 (normalize (vd), length (vd)); vim[2] = vec3 (0., -1.2, -3.); vd = vec3 (0., -0.5, -4.5) - vim[2]; vum[2] = vec4 (normalize (vd), length (vd)); vim[3] = vec3 (0., -2.7, -3.); vd = vec3 (0., -2.7, -4.5) - vim[3]; vum[3] = vec4 (normalize (vd), length (vd)); vir[0] = vec3 (0., -3., -4.45); vd = vec3 (0., -2.7, -4.5) - vir[0]; vur[0] = vec4 (normalize (vd), length (vd)); vir[1] = vec3 (0., 2.45, 2.65); vd = vec3 (0., -2.7, 6.5) - vir[1]; vur[1] = vec4 (normalize (vd), length (vd)); vir[2] = vec3 (0., 2.5, 2.65); vd = vec3 (0., -3.2, 4.9) - vir[2]; vur[2] = vec4 (normalize (vd), length (vd)); vir[3] = vec3 (0., 2.6, -3.); vd = vec3 (0., -0.5, -4.5) - vir[3]; vur[3] = vec4 (normalize (vd), length (vd)); vir[4] = vec3 (0.65, -3.5, 3.5); vd = vec3 (0.05, -2.7, 6.4) - vir[4]; vur[4] = vec4 (normalize (vd), length (vd)); } vec3 ShowScene (vec3 ro, vec3 rd) { vec4 col4; vec3 col, vn; vec2 vf; float dstObj, reflFac, dstWat; htWat = -1.5; cloudDisp = -0.05 * tCur * vec3 (1., 0., 1.); szFac = 1.; EvalShipConf (); isRefl = false; reflFac = 1.; dstObj = ObjRay (ro, rd); if (rd.y < 0. && dstObj >= dstFar) { isRefl = true; dstWat = - (ro.y - htWat) / rd.y; ro += dstWat * rd; rd = reflect (rd, WaveNf (ro.xz, dstWat)); ro += 0.01 * rd; dstObj = ObjRay (ro, rd); reflFac *= 0.8; } if (dstObj < dstFar) { ro += rd * dstObj; vn = ObjNf (ro); col4 = (idObj <= idRig) ? ShipCol () : BirdCol (vn); col4.gb *= 0.7; col = reflFac * (col4.rgb * (0.2 + 0.8 * max (dot (vn, sunDir), 0.)) + col4.a * pow (max (dot (normalize (sunDir - rd), vn), 0.), 128.)); } else { col = SkyCol (ro, rd); if (isRefl) col = reflFac * 0.7 * pow (col, vec3 (0.8)); } return col; } vec3 BirdTrack (float t) { vec3 bp, tt, fbR; float ti[9], rdTurn, tC, tCyc, tSeq, a, h, hd, tf, rSeg; rdTurn = 0.45 * min (fltBox.x, fltBox.z); tC = 0.5 * pi * rdTurn / birdVel; tt = vec3 (fltBox.x - rdTurn, length (fltBox.xy), fltBox.z - rdTurn) * 2. / birdVel; tCyc = 2. * (2. * tt.z + tt.x + 4. * tC + tt.y); tSeq = mod (t, tCyc); ti[0] = 0.; ti[1] = ti[0] + tt.z; ti[2] = ti[1] + tC; ti[3] = ti[2] + tt.x; ti[4] = ti[3] + tC; ti[5] = ti[4] + tt.z; ti[6] = ti[5] + tC; ti[7] = ti[6] + tt.y; ti[8] = ti[7] + tC; h = - fltBox.y; hd = 1.; if (tSeq > 0.5 * tCyc) { tSeq -= 0.5 * tCyc; h = - h; hd = - hd; } rSeg = -1.; fbR = vec3 (1.); fbR.xz -= vec2 (rdTurn) / fltBox.xz; bp.xz = fltBox.xz; bp.y = h; if (tSeq < ti[4]) { if (tSeq < ti[1]) { tf = (tSeq - ti[0]) / (ti[1] - ti[0]); bp.xz *= vec2 (1., fbR.z * (2. * tf - 1.)); } else if (tSeq < ti[2]) { tf = (tSeq - ti[1]) / (ti[2] - ti[1]); rSeg = 0.; bp.xz *= fbR.xz; } else if (tSeq < ti[3]) { tf = (tSeq - ti[2]) / (ti[3] - ti[2]); bp.xz *= vec2 (fbR.x * (1. - 2. * tf), 1.); } else { tf = (tSeq - ti[3]) / (ti[4] - ti[3]); rSeg = 1.; bp.xz *= fbR.xz * vec2 (-1., 1.); } } else { if (tSeq < ti[5]) { tf = (tSeq - ti[4]) / (ti[5] - ti[4]); bp.xz *= vec2 (- 1., fbR.z * (1. - 2. * tf)); } else if (tSeq < ti[6]) { tf = (tSeq - ti[5]) / (ti[6] - ti[5]); rSeg = 2.; bp.xz *= - fbR.xz; } else if (tSeq < ti[7]) { tf = (tSeq - ti[6]) / (ti[7] - ti[6]); bp.xz *= vec2 (fbR.x * (2. * tf - 1.), - 1.); bp.y = h + 2. * fltBox.y * hd * tf; } else { tf = (tSeq - ti[7]) / (ti[8] - ti[7]); rSeg = 3.; bp.xz *= fbR.xz * vec2 (1., -1.); bp.y = - h; } } if (rSeg >= 0.) { a = 0.5 * pi * (rSeg + tf); bp += rdTurn * vec3 (cos (a), 0., sin (a)); } bp.y -= - fltBox.y - htWat; bp.xz = vec2 (- bp.z, bp.x); return bp; } void BirdPM (float t) { vec3 bpF, bpB, vel, acc, va, ort, cr, sr; float dt, vy, el; dt = 1.; bdPos = BirdTrack (t); bpF = BirdTrack (t + dt); bpB = BirdTrack (t - dt); vel = (bpF - bpB) / (2. * dt); vy = vel.y; vel.y = 0.; acc = (bpF - 2. * bdPos + bpB) / (dt * dt); acc.y = 0.; va = cross (acc, vel) / length (vel); vel.y = vy; el = - 0.7 * asin (vel.y / length (vel)); ort = vec3 (el, atan (vel.z, vel.x) - 0.5 * pi, 0.2 * length (va) * sign (va.y)); cr = cos (ort); sr = sin (ort); bdMat = mat3 (cr.z, - sr.z, 0., sr.z, cr.z, 0., 0., 0., 1.) * mat3 (1., 0., 0., 0., cr.x, - sr.x, 0., sr.x, cr.x) * mat3 (cr.y, 0., - sr.y, 0., 1., 0., sr.y, 0., cr.y); legAng = pi * clamp (0.4 + 1.5 * el, 0.12, 0.8); } void mainImage (out vec4 fragColor, vec2 fragCoord) { vec3 ro, rd; vec2 canvas, uv; canvas = iResolution.xy; uv = 2. * fragCoord.xy / canvas - 1.; uv.x *= canvas.x / canvas.y; tCur = iTime; birdLen = 0.5; birdVel = 5.; fltBox = vec3 (12., 4., 12.); BirdPM (tCur); birdMat[0] = bdMat; birdPos[0] = bdPos; BirdPM (tCur + 10.); birdMat[1] = bdMat; birdPos[1] = bdPos; ro = vec3 (0., 3., -30.); rd = normalize (vec3 (uv, 2.5)); sunDir = normalize (vec3 (0., 0.05, 1.)); dstFar = 100.; fragColor = vec4 (ShowScene (ro, rd), 1.); } float PrBoxDf (vec3 p, vec3 b) { vec3 d; d = abs (p) - b; return min (max (d.x, max (d.y, d.z)), 0.) + length (max (d, 0.)); } float PrBox2Df (vec2 p, vec2 b) { vec2 d; d = abs (p) - b; return min (max (d.x, d.y), 0.) + length (max (d, 0.)); } float PrCapsDf (vec3 p, float r, float h) { return length (p - vec3 (0., 0., clamp (p.z, - h, h))) - r; } float PrEVCapsDf (vec3 p, vec4 u, float r) { return length (p - clamp (dot (p, u.xyz), 0., u.w) * u.xyz) - r; } float PrEECapsDf (vec3 p, vec3 v1, vec3 v2, float r) { return PrEVCapsDf (p - v1, vec4 (normalize (v2 - v1), length (v2 - v1)), r); } float PrSphDf (vec3 p, float r) { return length (p) - r; } float PrCylDf (vec3 p, float r, float h) { return max (length (p.xy) - r, abs (p.z) - h); } float PrFlatCylDf (vec3 p, float rhi, float rlo, float h) { return max (length (p.xy - vec2 (rhi * clamp (p.x / rhi, -1., 1.), 0.)) - rlo, abs (p.z) - h); } float PrTorusDf (vec3 p, float ri, float rc) { return length (vec2 (length (p.xy) - rc, p.z)) - ri; } float SmoothMin (float a, float b, float r) { float h; h = clamp (0.5 + 0.5 * (b - a) / r, 0., 1.); return mix (b, a, h) - r * h * (1. - h); } float SmoothBump (float lo, float hi, float w, float x) { return (1. - smoothstep (hi - w, hi + w, x)) * smoothstep (lo - w, lo + w, x); } vec2 Rot2D (vec2 q, float a) { return q * cos (a) * vec2 (1., 1.) + q.yx * sin (a) * vec2 (-1., 1.); } const float cHashM = 43758.54; vec2 Hashv2v2 (vec2 p) { vec2 cHashVA2 = vec2 (37., 39.); return fract (sin (vec2 (dot (p, cHashVA2), dot (p + vec2 (1., 0.), cHashVA2))) * cHashM); } float Noisefv2 (vec2 p) { vec2 t, ip, fp; ip = floor (p); fp = fract (p); fp = fp * fp * (3. - 2. * fp); t = mix (Hashv2v2 (ip), Hashv2v2 (ip + vec2 (0., 1.)), fp.y); return mix (t.x, t.y, fp.x); } float Fbm2 (vec2 p) { float f, a; f = 0.; a = 1.; for (int i = 0; i < 5; i ++) { f += a * Noisefv2 (p); a *= 0.5; p *= 2.; } return f * (1. / 1.9375); }

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