translate the following shader to our framework: // CC0: Let's self reflect // Always enjoyed the videos of Platonic solids with inner mirrors // I made some previous attempts but thought I make another attempt it // Reducing the alias effects on the inner reflections turned out to be a bit tricky. // Simplest solution is just to run run fullscreen on a 4K screen ;) // Function to generate the solid found here: https://www.shadertoy.com/view/MsKGzw // Tinker with these parameters to create different solids // ------------------------------------------------------- const float rotation_speed= 0.25; const float poly_U = 1.; // [0, inf] const float poly_V = 0.5; // [0, inf] const float poly_W = 1.0; // [0, inf] const int poly_type = 3; // [2, 5] const float poly_zoom = 2.0; const float inner_sphere = 1.; const float refr_index = 0.9; #define MAX_BOUNCES2 6 // ------------------------------------------------------- #define TIME iTime #define RESOLUTION iResolution #define PI 3.141592654 #define TAU (2.0*PI) // License: WTFPL, author: sam hocevar, found: https://stackoverflow.com/a/17897228/418488 const vec4 hsv2rgb_K = vec4(1.0, 2.0 / 3.0, 1.0 / 3.0, 3.0); vec3 hsv2rgb(vec3 c) { vec3 p = abs(fract(c.xxx + hsv2rgb_K.xyz) * 6.0 - hsv2rgb_K.www); return c.z * mix(hsv2rgb_K.xxx, clamp(p - hsv2rgb_K.xxx, 0.0, 1.0), c.y); } // License: WTFPL, author: sam hocevar, found: https://stackoverflow.com/a/17897228/418488 // Macro version of above to enable compile-time constants #define HSV2RGB(c) (c.z * mix(hsv2rgb_K.xxx, clamp(abs(fract(c.xxx + hsv2rgb_K.xyz) * 6.0 - hsv2rgb_K.www) - hsv2rgb_K.xxx, 0.0, 1.0), c.y)) #define TOLERANCE2 0.0005 //#define MAX_RAY_LENGTH2 10.0 #define MAX_RAY_MARCHES2 50 #define NORM_OFF2 0.005 #define BACKSTEP2 #define TOLERANCE3 0.0005 #define MAX_RAY_LENGTH3 10.0 #define MAX_RAY_MARCHES3 90 #define NORM_OFF3 0.005 const vec3 rayOrigin = vec3(0.0, 1., -5.); const vec3 sunDir = normalize(-rayOrigin); const vec3 sunCol = HSV2RGB(vec3(0.06 , 0.90, 1E-2))*1.; const vec3 bottomBoxCol = HSV2RGB(vec3(0.66, 0.80, 0.5))*1.; const vec3 topBoxCol = HSV2RGB(vec3(0.60, 0.90, 1.))*1.; const vec3 glowCol0 = HSV2RGB(vec3(0.05 , 0.7, 1E-3))*1.; const vec3 glowCol1 = HSV2RGB(vec3(0.95, 0.7, 1E-3))*1.; const vec3 beerCol = -HSV2RGB(vec3(0.15+0.5, 0.7, 2.)); const float rrefr_index = 1./refr_index; // License: Unknown, author: knighty, found: https://www.shadertoy.com/view/MsKGzw const float poly_cospin = cos(PI/float(poly_type)); const float poly_scospin = sqrt(0.75-poly_cospin*poly_cospin); const vec3 poly_nc = vec3(-0.5, -poly_cospin, poly_scospin); const vec3 poly_pab = vec3(0., 0., 1.); const vec3 poly_pbc_ = vec3(poly_scospin, 0., 0.5); const vec3 poly_pca_ = vec3(0., poly_scospin, poly_cospin); const vec3 poly_p = normalize((poly_U*poly_pab+poly_V*poly_pbc_+poly_W*poly_pca_)); const vec3 poly_pbc = normalize(poly_pbc_); const vec3 poly_pca = normalize(poly_pca_); mat3 g_rot; vec2 g_gd; // License: MIT, author: Inigo Quilez, found: https://iquilezles.org/articles/noacos/ mat3 rot(vec3 d, vec3 z) { vec3 v = cross( z, d ); float c = dot( z, d ); float k = 1.0/(1.0+c); return mat3( v.x*v.x*k + c, v.y*v.x*k - v.z, v.z*v.x*k + v.y, v.x*v.y*k + v.z, v.y*v.y*k + c, v.z*v.y*k - v.x, v.x*v.z*k - v.y, v.y*v.z*k + v.x, v.z*v.z*k + c ); } // License: Unknown, author: Matt Taylor (https://github.com/64), found: https://64.github.io/tonemapping/ vec3 aces_approx(vec3 v) { v = max(v, 0.0); v *= 0.6; float a = 2.51; float b = 0.03; float c = 2.43; float d = 0.59; float e = 0.14; return clamp((v*(a*v+b))/(v*(c*v+d)+e), 0.0, 1.0); } float sphere(vec3 p, float r) { return length(p) - r; } // License: MIT, author: Inigo Quilez, found: https://iquilezles.org/articles/distfunctions/ float box(vec2 p, vec2 b) { vec2 d = abs(p)-b; return length(max(d,0.0)) + min(max(d.x,d.y),0.0); } // License: Unknown, author: knighty, found: https://www.shadertoy.com/view/MsKGzw void poly_fold(inout vec3 pos) { vec3 p = pos; for(int i = 0; i < poly_type; ++i){ p.xy = abs(p.xy); p -= 2.*min(0., dot(p,poly_nc)) * poly_nc; } pos = p; } float poly_plane(vec3 pos) { float d0 = dot(pos, poly_pab); float d1 = dot(pos, poly_pbc); float d2 = dot(pos, poly_pca); float d = d0; d = max(d, d1); d = max(d, d2); return d; } float poly_corner(vec3 pos) { float d = length(pos) - .0125; return d; } float dot2(vec3 p) { return dot(p, p); } float poly_edge(vec3 pos) { float dla = dot2(pos-min(0., pos.x)*vec3(1., 0., 0.)); float dlb = dot2(pos-min(0., pos.y)*vec3(0., 1., 0.)); float dlc = dot2(pos-min(0., dot(pos, poly_nc))*poly_nc); return sqrt(min(min(dla, dlb), dlc))-2E-3; } vec3 shape(vec3 pos) { pos *= g_rot; pos /= poly_zoom; poly_fold(pos); pos -= poly_p; return vec3(poly_plane(pos), poly_edge(pos), poly_corner(pos))*poly_zoom; } vec3 render0(vec3 ro, vec3 rd) { vec3 col = vec3(0.0); float srd = sign(rd.y); float tp = -(ro.y-6.)/abs(rd.y); if (srd < 0.) { col += bottomBoxCol*exp(-0.5*(length((ro + tp*rd).xz))); } if (srd > 0.0) { vec3 pos = ro + tp*rd; vec2 pp = pos.xz; float db = box(pp, vec2(5.0, 9.0))-3.0; col += topBoxCol*rd.y*rd.y*smoothstep(0.25, 0.0, db); col += 0.2*topBoxCol*exp(-0.5*max(db, 0.0)); col += 0.05*sqrt(topBoxCol)*max(-db, 0.0); } col += sunCol/(1.001-dot(sunDir, rd)); return col; } float df2(vec3 p) { vec3 ds = shape(p); float d2 = ds.y-5E-3; float d0 = min(-ds.x, d2); float d1 = sphere(p, inner_sphere); g_gd = min(g_gd, vec2(d2, d1)); float d = (min(d0, d1)); return d; } float rayMarch2(vec3 ro, vec3 rd, float tinit) { float t = tinit; #if defined(BACKSTEP2) vec2 dti = vec2(1e10,0.0); #endif int i; for (i = 0; i < MAX_RAY_MARCHES2; ++i) { float d = df2(ro + rd*t); #if defined(BACKSTEP2) if (d<dti.x) { dti=vec2(d,t); } #endif // Bouncing in a closed shell, will never miss if (d < TOLERANCE2/* || t > MAX_RAY_LENGTH3 */) { break; } t += d; } #if defined(BACKSTEP2) if(i==MAX_RAY_MARCHES2) { t=dti.y; }; #endif return t; } vec3 normal2(vec3 pos) { vec2 eps = vec2(NORM_OFF2,0.0); vec3 nor; nor.x = df2(pos+eps.xyy) - df2(pos-eps.xyy); nor.y = df2(pos+eps.yxy) - df2(pos-eps.yxy); nor.z = df2(pos+eps.yyx) - df2(pos-eps.yyx); return normalize(nor); } vec3 render2(vec3 ro, vec3 rd, float db) { vec3 agg = vec3(0.0); float ragg = 1.; float tagg = 0.; for (int bounce = 0; bounce < MAX_BOUNCES2; ++bounce) { if (ragg < 0.1) break; g_gd = vec2(1E3); float t2 = rayMarch2(ro, rd, min(db+0.05, 0.3)); vec2 gd2 = g_gd; tagg += t2; vec3 p2 = ro+rd*t2; vec3 n2 = normal2(p2); vec3 r2 = reflect(rd, n2); vec3 rr2 = refract(rd, n2, rrefr_index); float fre2= 1.+dot(n2,rd); vec3 beer = ragg*exp(0.2*beerCol*tagg); agg += glowCol1*beer*((1.+tagg*tagg*4E-2)*6./max(gd2.x, 5E-4+tagg*tagg*2E-4/ragg)); vec3 ocol = 0.2*beer*render0(p2, rr2); if (gd2.y <= TOLERANCE2) { ragg *= 1.-0.9*fre2; } else { agg += ocol; ragg *= 0.8; } ro = p2; rd = r2; db = gd2.x; } return agg; } float df3(vec3 p) { vec3 ds = shape(p); g_gd = min(g_gd, ds.yz); const float sw = 0.02; float d1 = min(ds.y, ds.z)-sw; float d0 = ds.x; d0 = min(d0, ds.y); d0 = min(d0, ds.z); return d0; } float rayMarch3(vec3 ro, vec3 rd, float tinit, out int iter) { float t = tinit; int i; for (i = 0; i < MAX_RAY_MARCHES3; ++i) { float d = df3(ro + rd*t); if (d < TOLERANCE3 || t > MAX_RAY_LENGTH3) { break; } t += d; } iter = i; return t; } vec3 normal3(vec3 pos) { vec2 eps = vec2(NORM_OFF3,0.0); vec3 nor; nor.x = df3(pos+eps.xyy) - df3(pos-eps.xyy); nor.y = df3(pos+eps.yxy) - df3(pos-eps.yxy); nor.z = df3(pos+eps.yyx) - df3(pos-eps.yyx); return normalize(nor); } vec3 render3(vec3 ro, vec3 rd) { int iter; vec3 skyCol = render0(ro, rd); vec3 col = skyCol; g_gd = vec2(1E3); float t1 = rayMarch3(ro, rd, 0.1, iter); vec2 gd1 = g_gd; vec3 p1 = ro+t1*rd; vec3 n1 = normal3(p1); vec3 r1 = reflect(rd, n1); vec3 rr1 = refract(rd, n1, refr_index); float fre1= 1.+dot(rd, n1); fre1 *= fre1; float ifo = mix(0.5, 1., smoothstep(1.0, 0.9, float(iter)/float(MAX_RAY_MARCHES3))); if (t1 < MAX_RAY_LENGTH3) { col = render0(p1, r1)*(0.5+0.5*fre1)*ifo; vec3 icol = render2(p1, rr1, gd1.x); if (gd1.x > TOLERANCE3 && gd1.y > TOLERANCE3 && rr1 != vec3(0.)) { col += icol*(1.-0.75*fre1)*ifo; } } col += (glowCol0+1.*fre1*(glowCol0))/max(gd1.x, 3E-4); return col; } vec3 effect(vec2 p, vec2 pp) { const float fov = 2.0; const vec3 up = vec3(0., 1., 0.); const vec3 la = vec3(0.0); const vec3 ww = normalize(normalize(la-rayOrigin)); const vec3 uu = normalize(cross(up, ww)); const vec3 vv = cross(ww, uu); vec3 rd = normalize(-p.x*uu + p.y*vv + fov*ww); vec3 col = vec3(0.0); col = render3(rayOrigin, rd); col -= 2E-2*vec3(2.,3.,1.)*(length(p)+0.25); col = aces_approx(col); col = sqrt(col); return col; } void mainImage( out vec4 fragColor, in vec2 fragCoord ) { vec2 q = fragCoord/RESOLUTION.xy; vec2 p = -1. + 2. * q; vec2 pp = p; p.x *= RESOLUTION.x/RESOLUTION.y; float a = TIME*rotation_speed; vec3 r0 = vec3(1.0, sin(vec2(sqrt(0.5), 1.0)*a)); vec3 r1 = vec3(cos(vec2(sqrt(0.5), 1.0)*0.913*a), 1.0); mat3 rot = rot(normalize(r0), normalize(r1)); g_rot = rot; vec3 col = effect(p, pp); fragColor = vec4(col, 1.0); } Dynamic Mesh