diff --git a/shaders/lib/hg_sdf.glsl b/shaders/lib/hg_sdf.glsl new file mode 100644 index 0000000..a9285c0 --- /dev/null +++ b/shaders/lib/hg_sdf.glsl @@ -0,0 +1,724 @@ +//////////////////////////////////////////////////////////////// +// +// HG_SDF +// +// GLSL LIBRARY FOR BUILDING SIGNED DISTANCE BOUNDS +// +// version 2016-01-10 +// +// Check http://mercury.sexy/hg_sdf for updates +// and usage examples. Send feedback to spheretracing@mercury.sexy. +// +// Brought to you by MERCURY http://mercury.sexy +// +// +// +// Released as Creative Commons Attribution-NonCommercial (CC BY-NC) +// +//////////////////////////////////////////////////////////////// +// +// How to use this: +// +// 1. Build some system to #include glsl files in each other. +// Include this one at the very start. Or just paste everywhere. +// 2. Build a sphere tracer. See those papers: +// * "Sphere Tracing" http://graphics.cs.illinois.edu/sites/default/files/zeno.pdf +// * "Enhanced Sphere Tracing" http://lgdv.cs.fau.de/get/2234 +// The Raymnarching Toolbox Thread on pouet can be helpful as well +// http://www.pouet.net/topic.php?which=7931&page=1 +// and contains links to many more resources. +// 3. Use the tools in this library to build your distance bound f(). +// 4. ??? +// 5. Win a compo. +// +// (6. Buy us a beer or a good vodka or something, if you like.) +// +//////////////////////////////////////////////////////////////// +// +// Table of Contents: +// +// * Helper functions and macros +// * Collection of some primitive objects +// * Domain Manipulation operators +// * Object combination operators +// +//////////////////////////////////////////////////////////////// +// +// Why use this? +// +// The point of this lib is that everything is structured according +// to patterns that we ended up using when building geometry. +// It makes it more easy to write code that is reusable and that somebody +// else can actually understand. Especially code on Shadertoy (which seems +// to be what everybody else is looking at for "inspiration") tends to be +// really ugly. So we were forced to do something about the situation and +// release this lib ;) +// +// Everything in here can probably be done in some better way. +// Please experiment. We'd love some feedback, especially if you +// use it in a scene production. +// +// The main patterns for building geometry this way are: +// * Stay Lipschitz continuous. That means: don't have any distance +// gradient larger than 1. Try to be as close to 1 as possible - +// Distances are euclidean distances, don't fudge around. +// Underestimating distances will happen. That's why calling +// it a "distance bound" is more correct. Don't ever multiply +// distances by some value to "fix" a Lipschitz continuity +// violation. The invariant is: each fSomething() function returns +// a correct distance bound. +// * Use very few primitives and combine them as building blocks +// using combine opertors that preserve the invariant. +// * Multiply objects by repeating the domain (space). +// If you are using a loop inside your distance function, you are +// probably doing it wrong (or you are building boring fractals). +// * At right-angle intersections between objects, build a new local +// coordinate system from the two distances to combine them in +// interesting ways. +// * As usual, there are always times when it is best to not follow +// specific patterns. +// +//////////////////////////////////////////////////////////////// +// +// FAQ +// +// Q: Why is there no sphere tracing code in this lib? +// A: Because our system is way too complex and always changing. +// This is the constant part. Also we'd like everyone to +// explore for themselves. +// +// Q: This does not work when I paste it into Shadertoy!!!! +// A: Yes. It is GLSL, not GLSL ES. We like real OpenGL +// because it has way more features and is more likely +// to work compared to browser-based WebGL. We recommend +// you consider using OpenGL for your productions. Most +// of this can be ported easily though. +// +// Q: How do I material? +// A: We recommend something like this: +// Write a material ID, the distance and the local coordinate +// p into some global variables whenever an object's distance is +// smaller than the stored distance. Then, at the end, evaluate +// the material to get color, roughness, etc., and do the shading. +// +// Q: I found an error. Or I made some function that would fit in +// in this lib. Or I have some suggestion. +// A: Awesome! Drop us a mail at spheretracing@mercury.sexy. +// +// Q: Why is this not on github? +// A: Because we were too lazy. If we get bugged about it enough, +// we'll do it. +// +// Q: Your license sucks for me. +// A: Oh. What should we change it to? +// +// Q: I have trouble understanding what is going on with my distances. +// A: Some visualization of the distance field helps. Try drawing a +// plane that you can sweep through your scene with some color +// representation of the distance field at each point and/or iso +// lines at regular intervals. Visualizing the length of the +// gradient (or better: how much it deviates from being equal to 1) +// is immensely helpful for understanding which parts of the +// distance field are broken. +// +//////////////////////////////////////////////////////////////// + + + +//! type library +//! include lib/utils.glsl + + + + +//////////////////////////////////////////////////////////////// +// +// PRIMITIVE DISTANCE FUNCTIONS +// +//////////////////////////////////////////////////////////////// +// +// Conventions: +// +// Everything that is a distance function is called fSomething. +// The first argument is always a point in 2 or 3-space called

. +// Unless otherwise noted, (if the object has an intrinsic "up" +// side or direction) the y axis is "up" and the object is +// centered at the origin. +// +//////////////////////////////////////////////////////////////// + +float HG_fSphere(vec3 p, float r) { + return length(p) - r; +} + +// Plane with normal n (n is normalized) at some distance from the origin +float HG_fPlane(vec3 p, vec3 n, float distanceFromOrigin) { + return dot(p, n) + distanceFromOrigin; +} + +// Cheap Box: distance to corners is overestimated +float HG_fBoxCheap(vec3 p, vec3 b) { //cheap box + return M_VecMax(abs(p) - b); +} + +// Box: correct distance to corners +float HG_fBox(vec3 p, vec3 b) { + vec3 d = abs(p) - b; + return length(max(d, vec3(0))) + M_VecMax(min(d, vec3(0))); +} + +// Same as above, but in two dimensions (an endless box) +float HG_fBox2Cheap(vec2 p, vec2 b) { + return M_VecMax(abs(p)-b); +} + +float HG_fBox2(vec2 p, vec2 b) { + vec2 d = abs(p) - b; + return length(max(d, vec2(0))) + M_VecMax(min(d, vec2(0))); +} + + +// Endless "corner" +float HG_fCorner (vec2 p) { + return length(max(p, vec2(0))) + M_VecMax(min(p, vec2(0))); +} + +// Blobby ball object. You've probably seen it somewhere. This is not a correct distance bound, beware. +float HG_fBlob(vec3 p) { + p = abs(p); + if (p.x < max(p.y, p.z)) p = p.yzx; + if (p.x < max(p.y, p.z)) p = p.yzx; + float b = max(max(max( + dot(p, normalize(vec3(1, 1, 1))), + dot(p.xz, normalize(vec2(PHI+1, 1)))), + dot(p.yx, normalize(vec2(1, PHI)))), + dot(p.xz, normalize(vec2(1, PHI)))); + float l = length(p); + return l - 1.5 - 0.2 * (1.5 / 2)* cos(min(sqrt(1.01 - b / l)*(PI / 0.25), PI)); +} + +// Cylinder standing upright on the xz plane +float HG_fCylinder(vec3 p, float r, float height) { + float d = length(p.xz) - r; + d = max(d, abs(p.y) - height); + return d; +} + +// Capsule: A Cylinder with round caps on both sides +float HG_fCapsule(vec3 p, float r, float c) { + return mix(length(p.xz) - r, length(vec3(p.x, abs(p.y) - c, p.z)) - r, step(c, abs(p.y))); +} + +// Distance to line segment between and , used for fCapsule() version 2below +float HG_fLineSegment(vec3 p, vec3 a, vec3 b) { + vec3 ab = b - a; + float t = M_Saturate(dot(p - a, ab) / dot(ab, ab)); + return length((ab*t + a) - p); +} + +// Capsule version 2: between two end points and with radius r +float HG_fCapsule(vec3 p, vec3 a, vec3 b, float r) { + return HG_fLineSegment(p, a, b) - r; +} + +// Torus in the XZ-plane +float HG_fTorus(vec3 p, float smallRadius, float largeRadius) { + return length(vec2(length(p.xz) - largeRadius, p.y)) - smallRadius; +} + +// A circle line. Can also be used to make a torus by subtracting the smaller radius of the torus. +float HG_fCircle(vec3 p, float r) { + float l = length(p.xz) - r; + return length(vec2(p.y, l)); +} + +// A circular disc with no thickness (i.e. a cylinder with no height). +// Subtract some value to make a flat disc with rounded edge. +float HG_fDisc(vec3 p, float r) { + float l = length(p.xz) - r; + return l < 0 ? abs(p.y) : length(vec2(p.y, l)); +} + +// Hexagonal prism, circumcircle variant +float HG_fHexagonCircumcircle(vec3 p, vec2 h) { + vec3 q = abs(p); + return max(q.y - h.y, max(q.x*sqrt(3)*0.5 + q.z*0.5, q.z) - h.x); + //this is mathematically equivalent to this line, but less efficient: + //return max(q.y - h.y, max(dot(vec2(cos(PI/3), sin(PI/3)), q.zx), q.z) - h.x); +} + +// Hexagonal prism, incircle variant +float HG_fHexagonIncircle(vec3 p, vec2 h) { + return HG_fHexagonCircumcircle(p, vec2(h.x*sqrt(3)*0.5, h.y)); +} + +// Cone with correct distances to tip and base circle. Y is up, 0 is in the middle of the base. +float HG_fCone(vec3 p, float radius, float height) { + vec2 q = vec2(length(p.xz), p.y); + vec2 tip = q - vec2(0, height); + vec2 mantleDir = normalize(vec2(height, radius)); + float mantle = dot(tip, mantleDir); + float d = max(mantle, -q.y); + float projected = dot(tip, vec2(mantleDir.y, -mantleDir.x)); + + // distance to tip + if ((q.y > height) && (projected < 0)) { + d = max(d, length(tip)); + } + + // distance to base ring + if ((q.x > radius) && (projected > length(vec2(height, radius)))) { + d = max(d, length(q - vec2(radius, 0))); + } + return d; +} + +// +// "Generalized Distance Functions" by Akleman and Chen. +// see the Paper at https://www.viz.tamu.edu/faculty/ergun/research/implicitmodeling/papers/sm99.pdf +// +// This set of constants is used to construct a large variety of geometric primitives. +// Indices are shifted by 1 compared to the paper because we start counting at Zero. +// Some of those are slow whenever a driver decides to not unroll the loop, +// which seems to happen for fIcosahedron und fTruncatedIcosahedron on nvidia 350.12 at least. +// Specialized implementations can well be faster in all cases. +// + +const vec3 HG_GDFVectors[19] = vec3[]( + normalize(vec3(1, 0, 0)), + normalize(vec3(0, 1, 0)), + normalize(vec3(0, 0, 1)), + + normalize(vec3(1, 1, 1 )), + normalize(vec3(-1, 1, 1)), + normalize(vec3(1, -1, 1)), + normalize(vec3(1, 1, -1)), + + normalize(vec3(0, 1, PHI+1)), + normalize(vec3(0, -1, PHI+1)), + normalize(vec3(PHI+1, 0, 1)), + normalize(vec3(-PHI-1, 0, 1)), + normalize(vec3(1, PHI+1, 0)), + normalize(vec3(-1, PHI+1, 0)), + + normalize(vec3(0, PHI, 1)), + normalize(vec3(0, -PHI, 1)), + normalize(vec3(1, 0, PHI)), + normalize(vec3(-1, 0, PHI)), + normalize(vec3(PHI, 1, 0)), + normalize(vec3(-PHI, 1, 0)) +); + +// Version with variable exponent. +// This is slow and does not produce correct distances, but allows for bulging of objects. +float HG_fGDF(vec3 p, float r, float e, int begin, int end) { + float d = 0; + for (int i = begin; i <= end; ++i) + d += pow(abs(dot(p, HG_GDFVectors[i])), e); + return pow(d, 1/e) - r; +} + +// Version with without exponent, creates objects with sharp edges and flat faces +float HG_fGDF(vec3 p, float r, int begin, int end) { + float d = 0; + for (int i = begin; i <= end; ++i) + d = max(d, abs(dot(p, HG_GDFVectors[i]))); + return d - r; +} + +// Primitives follow: + +float HG_fOctahedron(vec3 p, float r, float e) { + return HG_fGDF(p, r, e, 3, 6); +} + +float HG_fDodecahedron(vec3 p, float r, float e) { + return HG_fGDF(p, r, e, 13, 18); +} + +float HG_fIcosahedron(vec3 p, float r, float e) { + return HG_fGDF(p, r, e, 3, 12); +} + +float HG_fTruncatedOctahedron(vec3 p, float r, float e) { + return HG_fGDF(p, r, e, 0, 6); +} + +float HG_fTruncatedIcosahedron(vec3 p, float r, float e) { + return HG_fGDF(p, r, e, 3, 18); +} + +float HG_fOctahedron(vec3 p, float r) { + return HG_fGDF(p, r, 3, 6); +} + +float HG_fDodecahedron(vec3 p, float r) { + return HG_fGDF(p, r, 13, 18); +} + +float HG_fIcosahedron(vec3 p, float r) { + return HG_fGDF(p, r, 3, 12); +} + +float HG_fTruncatedOctahedron(vec3 p, float r) { + return HG_fGDF(p, r, 0, 6); +} + +float HG_fTruncatedIcosahedron(vec3 p, float r) { + return HG_fGDF(p, r, 3, 18); +} + + +//////////////////////////////////////////////////////////////// +// +// DOMAIN MANIPULATION OPERATORS +// +//////////////////////////////////////////////////////////////// +// +// Conventions: +// +// Everything that modifies the domain is named pSomething. +// +// Many operate only on a subset of the three dimensions. For those, +// you must choose the dimensions that you want manipulated +// by supplying e.g. or +// +// is always the first argument and modified in place. +// +// Many of the operators partition space into cells. An identifier +// or cell index is returned, if possible. This return value is +// intended to be optionally used e.g. as a random seed to change +// parameters of the distance functions inside the cells. +// +// Unless stated otherwise, for cell index 0,

is unchanged and cells +// are centered on the origin so objects don't have to be moved to fit. +// +// +//////////////////////////////////////////////////////////////// + + + +// Rotate around a coordinate axis (i.e. in a plane perpendicular to that axis) by angle . +// Read like this: R(p.xz, a) rotates "x towards z". +// This is fast if is a compile-time constant and slower (but still practical) if not. +void HG_pR(inout vec2 p, float a) { + p = cos(a)*p + sin(a)*vec2(p.y, -p.x); +} + +// Shortcut for 45-degrees rotation +void HG_pR45(inout vec2 p) { + p = (p + vec2(p.y, -p.x))*sqrt(0.5); +} + +// Repeat space along one axis. Use like this to repeat along the x axis: +// - using the return value is optional. +float HG_pMod1(inout float p, float size) { + float halfsize = size*0.5; + float c = floor((p + halfsize)/size); + p = mod(p + halfsize, size) - halfsize; + return c; +} + +// Same, but mirror every second cell so they match at the boundaries +float HG_pModMirror1(inout float p, float size) { + float halfsize = size*0.5; + float c = floor((p + halfsize)/size); + p = mod(p + halfsize,size) - halfsize; + p *= mod(c, 2.0)*2 - 1; + return c; +} + +// Repeat the domain only in positive direction. Everything in the negative half-space is unchanged. +float HG_pModSingle1(inout float p, float size) { + float halfsize = size*0.5; + float c = floor((p + halfsize)/size); + if (p >= 0) + p = mod(p + halfsize, size) - halfsize; + return c; +} + +// Repeat only a few times: from indices to (similar to above, but more flexible) +float HG_pModInterval1(inout float p, float size, float start, float stop) { + float halfsize = size*0.5; + float c = floor((p + halfsize)/size); + p = mod(p+halfsize, size) - halfsize; + if (c > stop) { //yes, this might not be the best thing numerically. + p += size*(c - stop); + c = stop; + } + if (c = (repetitions/2)) c = abs(c); + return c; +} + +// Repeat in two dimensions +vec2 HG_pMod2(inout vec2 p, vec2 size) { + vec2 c = floor((p + size*0.5)/size); + p = mod(p + size*0.5,size) - size*0.5; + return c; +} + +// Same, but mirror every second cell so all boundaries match +vec2 HG_pModMirror2(inout vec2 p, vec2 size) { + vec2 halfsize = size*0.5; + vec2 c = floor((p + halfsize)/size); + p = mod(p + halfsize, size) - halfsize; + p *= mod(c,vec2(2))*2 - vec2(1); + return c; +} + +// Same, but mirror every second cell at the diagonal as well +vec2 HG_pModGrid2(inout vec2 p, vec2 size) { + vec2 c = floor((p + size*0.5)/size); + p = mod(p + size*0.5, size) - size*0.5; + p *= mod(c,vec2(2))*2 - vec2(1); + p -= size/2; + if (p.x > p.y) p.xy = p.yx; + return floor(c/2); +} + +// Repeat in three dimensions +vec3 HG_pMod3(inout vec3 p, vec3 size) { + vec3 c = floor((p + size*0.5)/size); + p = mod(p + size*0.5, size) - size*0.5; + return c; +} + +// Mirror at an axis-aligned plane which is at a specified distance from the origin. +float HG_pMirror (inout float p, float dist) { + float s = M_Sign(p); + p = abs(p)-dist; + return s; +} + +// Mirror in both dimensions and at the diagonal, yielding one eighth of the space. +// translate by dist before mirroring. +vec2 HG_pMirrorOctant (inout vec2 p, vec2 dist) { + vec2 s = M_Sign(p); + HG_pMirror(p.x, dist.x); + HG_pMirror(p.y, dist.y); + if (p.y > p.x) + p.xy = p.yx; + return s; +} + +// Reflect space at a plane +float HG_pReflect(inout vec3 p, vec3 planeNormal, float offset) { + float t = dot(p, planeNormal)+offset; + if (t < 0) { + p = p - (2*t)*planeNormal; + } + return M_Sign(t); +} + + +//////////////////////////////////////////////////////////////// +// +// OBJECT COMBINATION OPERATORS +// +//////////////////////////////////////////////////////////////// +// +// We usually need the following boolean operators to combine two objects: +// Union: OR(a,b) +// Intersection: AND(a,b) +// Difference: AND(a,!b) +// (a and b being the distances to the objects). +// +// The trivial implementations are min(a,b) for union, max(a,b) for intersection +// and max(a,-b) for difference. To combine objects in more interesting ways to +// produce rounded edges, chamfers, stairs, etc. instead of plain sharp edges we +// can use combination operators. It is common to use some kind of "smooth minimum" +// instead of min(), but we don't like that because it does not preserve Lipschitz +// continuity in many cases. +// +// Naming convention: since they return a distance, they are called fOpSomething. +// The different flavours usually implement all the boolean operators above +// and are called fOpUnionRound, fOpIntersectionRound, etc. +// +// The basic idea: Assume the object surfaces intersect at a right angle. The two +// distances and constitute a new local two-dimensional coordinate system +// with the actual intersection as the origin. In this coordinate system, we can +// evaluate any 2D distance function we want in order to shape the edge. +// +// The operators below are just those that we found useful or interesting and should +// be seen as examples. There are infinitely more possible operators. +// +// They are designed to actually produce correct distances or distance bounds, unlike +// popular "smooth minimum" operators, on the condition that the gradients of the two +// SDFs are at right angles. When they are off by more than 30 degrees or so, the +// Lipschitz condition will no longer hold (i.e. you might get artifacts). The worst +// case is parallel surfaces that are close to each other. +// +// Most have a float argument to specify the radius of the feature they represent. +// This should be much smaller than the object size. +// +// Some of them have checks like "if ((-a < r) && (-b < r))" that restrict +// their influence (and computation cost) to a certain area. You might +// want to lift that restriction or enforce it. We have left it as comments +// in some cases. +// +// usage example: +// +// float fTwoBoxes(vec3 p) { +// float box0 = fBox(p, vec3(1)); +// float box1 = fBox(p-vec3(1), vec3(1)); +// return fOpUnionChamfer(box0, box1, 0.2); +// } +// +//////////////////////////////////////////////////////////////// + + +// The "Chamfer" flavour makes a 45-degree chamfered edge (the diagonal of a square of size ): +float HG_fOpUnionChamfer(float a, float b, float r) { + return min(min(a, b), (a - r + b)*sqrt(0.5)); +} + +// Intersection has to deal with what is normally the inside of the resulting object +// when using union, which we normally don't care about too much. Thus, intersection +// implementations sometimes differ from union implementations. +float HG_fOpIntersectionChamfer(float a, float b, float r) { + return max(max(a, b), (a + r + b)*sqrt(0.5)); +} + +// Difference can be built from Intersection or Union: +float HG_fOpDifferenceChamfer (float a, float b, float r) { + return HG_fOpIntersectionChamfer(a, -b, r); +} + +// The "Round" variant uses a quarter-circle to join the two objects smoothly: +float HG_fOpUnionRound(float a, float b, float r) { + vec2 u = max(vec2(r - a,r - b), vec2(0)); + return max(r, min (a, b)) - length(u); +} + +float HG_fOpIntersectionRound(float a, float b, float r) { + vec2 u = max(vec2(r + a,r + b), vec2(0)); + return min(-r, max (a, b)) + length(u); +} + +float HG_fOpDifferenceRound (float a, float b, float r) { + return HG_fOpIntersectionRound(a, -b, r); +} + + +// The "Columns" flavour makes n-1 circular columns at a 45 degree angle: +float HG_fOpUnionColumns(float a, float b, float r, float n) { + if ((a < r) && (b < r)) { + vec2 p = vec2(a, b); + float columnradius = r*sqrt(2)/((n-1)*2+sqrt(2)); + HG_pR45(p); + p.x -= sqrt(2)/2*r; + p.x += columnradius*sqrt(2); + if (mod(n,2) == 1) { + p.y += columnradius; + } + // At this point, we have turned 45 degrees and moved at a point on the + // diagonal that we want to place the columns on. + // Now, repeat the domain along this direction and place a circle. + HG_pMod1(p.y, columnradius*2); + float result = length(p) - columnradius; + result = min(result, p.x); + result = min(result, a); + return min(result, b); + } else { + return min(a, b); + } +} + +float HG_fOpDifferenceColumns(float a, float b, float r, float n) { + a = -a; + float m = min(a, b); + //avoid the expensive computation where not needed (produces discontinuity though) + if ((a < r) && (b < r)) { + vec2 p = vec2(a, b); + float columnradius = r*sqrt(2)/n/2.0; + columnradius = r*sqrt(2)/((n-1)*2+sqrt(2)); + + HG_pR45(p); + p.y += columnradius; + p.x -= sqrt(2)/2*r; + p.x += -columnradius*sqrt(2)/2; + + if (mod(n,2) == 1) { + p.y += columnradius; + } + HG_pMod1(p.y,columnradius*2); + + float result = -length(p) + columnradius; + result = max(result, p.x); + result = min(result, a); + return -min(result, b); + } else { + return -m; + } +} + +float fOpIntersectionColumns(float a, float b, float r, float n) { + return HG_fOpDifferenceColumns(a,-b,r, n); +} + +// The "Stairs" flavour produces n-1 steps of a staircase: +// much less stupid version by paniq +float HG_fOpUnionStairs(float a, float b, float r, float n) { + float s = r/n; + float u = b-r; + return min(min(a,b), 0.5 * (u + a + abs ((mod (u - a + s, 2 * s)) - s))); +} + +// We can just call Union since stairs are symmetric. +float fOpIntersectionStairs(float a, float b, float r, float n) { + return -HG_fOpUnionStairs(-a, -b, r, n); +} + +float fOpDifferenceStairs(float a, float b, float r, float n) { + return -HG_fOpUnionStairs(-a, b, r, n); +} + + +// Similar to fOpUnionRound, but more lipschitz-y at acute angles +// (and less so at 90 degrees). Useful when fudging around too much +// by MediaMolecule, from Alex Evans' siggraph slides +float HG_fOpUnionSoft(float a, float b, float r) { + float e = max(r - abs(a - b), 0); + return min(a, b) - e*e*0.25/r; +} + + +// produces a cylindical pipe that runs along the intersection. +// No objects remain, only the pipe. This is not a boolean operator. +float HG_fOpPipe(float a, float b, float r) { + return length(vec2(a, b)) - r; +} + +// first object gets a v-shaped engraving where it intersect the second +float HG_fOpEngrave(float a, float b, float r) { + return max(a, (a + r - abs(b))*sqrt(0.5)); +} + +// first object gets a capenter-style groove cut out +float HG_fOpGroove(float a, float b, float ra, float rb) { + return max(a, min(a + ra, rb - abs(b))); +} + +// first object gets a capenter-style tongue attached +float HG_fOpTongue(float a, float b, float ra, float rb) { + return min(a, max(a - ra, abs(b) - rb)); +} diff --git a/shaders/lib/utils.glsl b/shaders/lib/utils.glsl index 9d64c09..6d74e8d 100644 --- a/shaders/lib/utils.glsl +++ b/shaders/lib/utils.glsl @@ -1,7 +1,9 @@ //! type library -const float PI = 3.14159265; +const float PI = 3.1415926535; +const float TAU = 2 * PI; +const float PHI = sqrt( 5 ) * .5 + .5; // ----------------------------------------------------------------------------- @@ -42,3 +44,71 @@ float M_LengthSqr( { return dot( x , x ); } + +float M_Sqr( + in float x ) +{ + return x * x; +} + +vec2 M_Sqr( + in vec2 x ) +{ + return x * x; +} + +vec3 M_Sqr( + in vec3 x ) +{ + return x * x; +} + +float M_Sign( + in float x ) +{ + return ( x < 0 ) ? -1 : 1; +} + +vec2 M_Sign( + in vec2 v ) +{ + return vec2( M_Sign( v.x ) , M_Sign( v.y ) ); +} + + +float M_VecMax( + in vec2 v ) +{ + return max( v.x , v.y ); +} + +float M_VecMax( + in vec3 v ) +{ + return max( M_VecMax( v.xy ) , v.z ); +} + +float M_VecMax( + in vec4 v ) +{ + return max( M_VecMax( v.xy ) , M_VecMax( v.zw ) ); +} + + +float M_VecMin( + in vec2 v ) +{ + return min( v.x , v.y ); +} + +float M_VecMin( + in vec3 v ) +{ + return min( M_VecMin( v.xy ) , v.z ); +} + +float M_VecMin( + in vec4 v ) +{ + return min( M_VecMin( v.xy ) , M_VecMin( v.zw ) ); +} diff --git a/shaders/scene.f.glsl b/shaders/scene.f.glsl index 90c9bf6..ae68f11 100644 --- a/shaders/scene.f.glsl +++ b/shaders/scene.f.glsl @@ -2,6 +2,8 @@ //! type fragment //! include chunks/raymarcher.glsl +//! include lib/hg_sdf.glsl + //! include lib/shading-pbr.glsl //! include lib/shading-blinnphong.glsl //! include lib/fog.glsl