// Compatibility #ifdefs needed for parameters #ifdef GL_ES #define COMPAT_PRECISION mediump #else #define COMPAT_PRECISION #endif // Parameter lines go here: #pragma parameter RETRO_PIXEL_SIZE "Retro Pixel Size" 0.84 0.0 1.0 0.01 #ifdef PARAMETER_UNIFORM // All parameter floats need to have COMPAT_PRECISION in front of them uniform COMPAT_PRECISION float RETRO_PIXEL_SIZE; #else #define RETRO_PIXEL_SIZE 0.84 #endif #if defined(VERTEX) #if __VERSION__ >= 130 #define COMPAT_VARYING out #define COMPAT_ATTRIBUTE in #define COMPAT_TEXTURE texture #else #define COMPAT_VARYING varying #define COMPAT_ATTRIBUTE attribute #define COMPAT_TEXTURE texture2D #endif #ifdef GL_ES #define COMPAT_PRECISION mediump #else #define COMPAT_PRECISION #endif COMPAT_ATTRIBUTE vec4 VertexCoord; COMPAT_ATTRIBUTE vec4 COLOR; COMPAT_ATTRIBUTE vec4 TexCoord; COMPAT_VARYING vec4 COL0; COMPAT_VARYING vec4 TEX0; // out variables go here as COMPAT_VARYING whatever vec4 _oPosition1; uniform mat4 MVPMatrix; uniform COMPAT_PRECISION int FrameDirection; uniform COMPAT_PRECISION int FrameCount; uniform COMPAT_PRECISION vec2 OutputSize; uniform COMPAT_PRECISION vec2 TextureSize; uniform COMPAT_PRECISION vec2 InputSize; // compatibility #defines #define vTexCoord TEX0.xy #define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize #define OutSize vec4(OutputSize, 1.0 / OutputSize) void main() { gl_Position = MVPMatrix * VertexCoord; TEX0.xy = VertexCoord.xy; // Paste vertex contents here: } #elif defined(FRAGMENT) #if __VERSION__ >= 130 #define COMPAT_VARYING in #define COMPAT_TEXTURE texture out vec4 FragColor; #else #define COMPAT_VARYING varying #define FragColor gl_FragColor #define COMPAT_TEXTURE texture2D #endif #ifdef GL_ES #ifdef GL_FRAGMENT_PRECISION_HIGH precision highp float; #else precision mediump float; #endif #define COMPAT_PRECISION mediump #else #define COMPAT_PRECISION #endif uniform COMPAT_PRECISION int FrameDirection; uniform COMPAT_PRECISION int FrameCount; uniform COMPAT_PRECISION vec2 OutputSize; uniform COMPAT_PRECISION vec2 TextureSize; uniform COMPAT_PRECISION vec2 InputSize; uniform sampler2D Texture; COMPAT_VARYING vec4 TEX0; // in variables go here as COMPAT_VARYING whatever // compatibility #defines #define Source Texture #define vTexCoord TEX0.xy #define SourceSize vec4(TextureSize, 1.0 / TextureSize) //either TextureSize or InputSize #define OutSize vec4(OutputSize, 1.0 / OutputSize) // delete all 'params.' or 'registers.' or whatever in the fragment float iGlobalTime = float(FrameCount)*0.025; vec2 iResolution = OutputSize.xy; /* Transparent Lattice ------------------- Just a transparent lattice. Not much different to my other transparent examples, except this one is point lit... In case it needs to be said, a lot of it is faked, so is more of a novelty than anything else. I wrote it some time ago, then forgot about it. I thought I'd put it up just in case it's of any use to anyone. It runs reasonably fast, considering that the lighting is calculated multiple times a pass, but could benefit from a little more tweaking. Related shaders: Cloudy Spikeball - Duke https://www.shadertoy.com/view/MljXDw // Port from a demo by Las - Worth watching. // http://www.pouet.net/topic.php?which=7920&page=29&x=14&y=9 Virtually the same thing, but with rounded cubes and less interesting lighting. Transparent Cube Field - Shane https://www.shadertoy.com/view/ll2SRy */ // Cheap vec3 to vec3 hash. Works well enough, but there are other ways. vec3 hash33(vec3 p){ float n = sin(dot(p, vec3(7, 157, 113))); return fract(vec3(2097152, 262144, 32768)*n); } /* // Rounded cube field, for comparison. It runs at full speed, believe it or not. float map(vec3 p){ // Creating the repeat cubes, with slightly convex faces. Standard, // flat faced cubes don't capture the light quite as well. // 3D space repetition. p = fract(p)-.5; // + o // A bit of roundness. Used to give the cube faces a touch of convexity. float r = dot(p, p) - 0.21; // Max of abs(x), abs(y) and abs(z) minus a constant gives a cube. // Adding a little bit of "r," above, rounds off the surfaces a bit. p = abs(p); return max(max(p.x, p.y), p.z)*.95 + r*0.25 - 0.21; // Alternative. Egg shapes... kind of. //float perturb = sin(p.x*10.)*sin(p.y*10.)*sin(p.z*10.); //p += hash33(floor(p))*.15; //return length(fract(p)-.5)-0.3 + perturb*0.05; } */ /* // A fake noise looking field. Pretty interesting. float map(vec3 p){ p = (cos(p*.315*2.5 + sin(p.zxy*.875*2.5))); // + iGlobalTime*.5 float n = length(p); p = sin(p*6. + cos(p.yzx*6.)); return n - 1. - abs(p.x*p.y*p.z)*.05; } */ float map(vec3 p){ vec2 c; // SECTION 1 // // Repeat field entity one, which is just some tubes repeated in all directions every // two units, then combined with a smooth minimum function. Otherwise known as a lattice. p = abs(fract(p/3.)*3.-1.5); //c.x = sminP(length(p.xy),sminP(length(p.yz),length(p.xz), 0.25), 0.25)-0.75; // EQN 1 //c.x = sqrt(min(dot(p.xy, p.xy),min(dot(p.yz, p.yz),dot(p.xz, p.xz))))-0.75; // EQN 2 c.x = min(max(p.x, p.y),min(max(p.y, p.z),max(p.x, p.z)))-0.75; // EQN 3 //p = abs(p); c.x = max(p.x,max(p.y,p.z)) - .5; // SECTION 2 // // Repeat field entity two, which is just an abstract object repeated every half unit. p = abs(fract(p*4./3.)*.75 - 0.375); c.y = min(p.x,min(p.y,p.z)); // EQN 1 //c.y = min(max(p.x, p.y),min(max(p.y, p.z),max(p.x, p.z)))-0.125; //-0.175, etc. // EQN 2 //c.y = max(p.x,max(p.y,p.z)) - .4; // SECTION 3 // // Combining the two entities above. //return length(c)-.1; // EQN 1 //return max(c.x, c.y)-.05; // EQN 2 return max(abs(c.x), abs(c.y))*.75 + length(c)*.25 - .1; //return max(abs(c.x), abs(c.y))*.75 + abs(c.x+c.y)*.25 - .1; //return max(abs(c.x), abs(c.y)) - .1; } // Not big on accuracy, but lower on operations. Few distance function calls are important // during volumetric passes. vec3 calcNormal(in vec3 p, float d) { const vec2 e = vec2(0.01, 0); return normalize(vec3(d - map(p - e.xyy), d - map(p - e.yxy), d - map(p - e.yyx))); } /* // Tetrahedral normal, to save a couple of "map" calls. Courtesy of IQ. Unfortunately, still // not fast enough in this particular instance. vec3 calcNormal(in vec3 p){ // Note the slightly increased sampling distance, to alleviate artifacts due to hit point inaccuracies. vec2 e = vec2(0.0025, -0.0025); return normalize(e.xyy * map(p + e.xyy) + e.yyx * map(p + e.yyx) + e.yxy * map(p + e.yxy) + e.x * map(p + e.xxx)); } */ void mainImage( out vec4 fragColor, vec2 fragCoord ) { // Screen coordinates. vec2 uv = (fragCoord.xy - iResolution.xy*.5 )/iResolution.y; // Unit direction ray. The last term is one of many ways to fish-lens the camera. // For a regular view, set "rd.z" to something like "0.5." vec3 rd = normalize(vec3(uv, (1.-dot(uv, uv)*.5)*.5)); // Fish lens, for that 1337, but tryhardish, demo look. :) // There are a few ways to hide artifacts and inconsistencies. Making things go fast is one of them. :) // Ray origin, scene color, and surface postion vector. vec3 ro = vec3(0., 0., iGlobalTime*1.5), col=vec3(0), sp, sn, lp, ld, rnd; // Swivel the unit ray to look around the scene. // Compact 2D rotation matrix, courtesy of Shadertoy user, "Fabrice Neyret." vec2 a = sin(vec2(1.5707963, 0) + iGlobalTime*0.375); rd.xz = mat2(a, -a.y, a.x)*rd.xz; rd.xy = mat2(a, -a.y, a.x)*rd.xy; lp = vec3(0, 1, 4); lp.xz = mat2(a, -a.y, a.x)*lp.xz; lp.xy = mat2(a, -a.y, a.x)*lp.xy; lp += ro; // Unit ray jitter is another way to hide artifacts. It can also trick the viewer into believing // something hard core, like global illumination, is happening. :) //rd *= 0.99 + hash33(rd)*0.02; // Some more randomization, to be used for color based jittering inside the loop. rnd = hash33(rd+311.); // Ray distance, bail out layer number, surface distance and normalized accumulated distance. float t=0., layers=0., d, aD; // Light variables. float lDist, s, l; // Surface distance threshold. Smaller numbers gives a thinner membrane, but lessens detail... // hard to explain. It's easier to check it out for yourself. float thD = .0125; // + smoothstep(-0.2, 0.2, sin(iGlobalTime*0.75 - 3.14159*0.4))*0.025; // Only a few iterations seemed to be enough. Obviously, more looks better, but is slower. for(float i=0.; i<64.; i++) { // Break conditions. Anything that can help you bail early usually increases frame rate. if(layers>31. || dot(col, vec3(.299, .587, .114)) > 1. || t>16.) break; // Current ray postion. Slightly redundant here, but sometimes you may wish to reuse // it during the accumulation stage. sp = ro+rd*t; d = map(sp); // Distance to nearest point on the noise surface. // If we get within a certain distance of the surface, accumulate some surface values. // Values further away have less influence on the total. // // aD - Accumulated distance. You could smoothly interpolate it, if you wanted. // // 1/.(1. + t*t*0.1) - Basic distance attenuation. Feel free to substitute your own. // Normalized distance from the surface threshold value to our current isosurface value. aD = (thD-abs(d)*31./32.)/thD; // If we're within the surface threshold, accumulate some color. // Two "if" statements in a shader loop makes me nervous. I don't suspect there'll be any // problems, but if there are, let us know. if(aD>0.) { // Add the accumulated surface distance value, along with some basic falloff using the // camera to light distance, "lDist." There's a bit of color jitter there, too. sn = calcNormal(sp, d)*sign(d); ld = (lp - sp); //vec3(.5773) lDist = max(length(ld), .001); ld /= lDist; s = pow(max(dot(reflect(-ld, sn), -rd), 0.), 8.); l = max(dot(ld, sn), 0.); //float c = dot(sin(sp*128. - cos(sp.yzx*64.)), vec3(.166))+.5; col += ((l + .1) + vec3(.5, .7, 1)*s)*aD/(1. + lDist*0.25 + lDist*lDist*0.05)*.2; // Failed experiment with color jitter to take out more banding. //col += ((l + .05 + fract(rnd + i*27.)*.1) + vec3(.5, .7, 1)*s)*aD/(1. + lDist*0.25 + lDist*lDist*0.05)*.2; // The layer number is worth noting. Accumulating more layers gives a bit more glow. // Lower layer numbers allow a quicker bailout. A lot of it is guess work. layers++; } // Kind of weird the way this works. I think not allowing the ray to hone in properly is // the very thing that gives an even spread of values. The figures are based on a bit // of knowledge versus trial and error. If you have a faster computer, feel free to tweak // them a bit. t += max(abs(d)*.75, thD*.25); } t = min(t, 16.); col = mix(col, vec3(0), 1.-exp(-0.025*t*t));////1.-exp(-0.01*t*t) 1.-1./(1. + t*t*.1) // Mixing the greytone color with a firey orange vignette. There's no meaning // behind it. I just thought the artsy greyscale was a little too artsy. uv = abs(fragCoord.xy/iResolution.xy - .5); // Wasteful, but the GPU can handle it. col = mix(col, vec3(min(col.x*1.5, 1.), pow(col.x, 2.5), pow(col.x, 12.)).yxz, min( dot(pow(uv, vec2(4.)), vec2(1))*8., 1.)); //col = vec3(min(col.z*1.5, 1.), pow(col.z, 2.5), pow(col.z, 12.)); // Mixing the vignette colors up a bit more. col = mix(col, col.zxy, dot(sin(rd*5.), vec3(.166)) + 0.166); // Presenting the color to the screen. fragColor = vec4( sqrt(clamp(col, 0., 1.)), 1.0 ); } void main(void) { //just some shit to wrap shadertoy's stuff vec2 FragCoord = vTexCoord.xy*OutputSize.xy; mainImage(FragColor,FragCoord); } #endif