Mercurial > projects > ldc
diff test/ray.d @ 92:70d6113eeb8c trunk
[svn r96] Updated to DMD 1.023.
Regular bugfixes.
author | lindquist |
---|---|
date | Thu, 08 Nov 2007 19:13:28 +0100 |
parents | |
children | 61615fa85940 |
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--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/test/ray.d Thu Nov 08 19:13:28 2007 +0100 @@ -0,0 +1,117 @@ +//import std.stdio, std.math, std.string; +//import tools.base; + +int atoi(char[] s) { + int i, fac=1; + bool neg = (s.length) && (s[0] == '-'); + char[] a = neg ? s[1..$] : s; + foreach_reverse(c; a) { + i += (c-'0') * fac; + fac *= 10; + } + return !neg ? i : -i; +} + +pragma(LLVM_internal, "intrinsic", "llvm.sqrt.f64") +double sqrt(double val); + +double delta; +static this() { delta=sqrt(real.epsilon); } + +struct Vec { + double x, y, z; + Vec opAdd(ref Vec other) { return Vec(x+other.x, y+other.y, z+other.z); } + Vec opSub(ref Vec other) { return Vec(x-other.x, y-other.y, z-other.z); } + Vec opMul(double a) { return Vec(x*a, y*a, z*a); } + double dot(ref Vec other) { return x*other.x+y*other.y+z*other.z; } + Vec unitise() { return opMul(1.0/sqrt(dot(*this))); } +} + +struct Pair(T, U) { T first; U second; } +typedef Pair!(double, Vec) Hit; + +struct Ray { Vec orig, dir; } + +class Scene { + //abstract void intersect(ref Hit, ref Ray); + void intersect(ref Hit, ref Ray) {} +} + +class Sphere : Scene { + Vec center; + double radius; + //mixin This!("center, radius"); + this(ref Vec c, double r) + { + center = c; + radius = r; + } + double ray_sphere(ref Ray ray) { + auto v = center - ray.orig, b = v.dot(ray.dir), disc=b*b - v.dot(v) + radius*radius; + if (disc < 0) return double.infinity; + auto d = sqrt(disc), t2 = b + d; + if (t2 < 0) return double.infinity; + auto t1 = b - d; + return (t1 > 0 ? t1 : t2); + } + void intersect(ref Hit hit, ref Ray ray) { + auto lambda = ray_sphere(ray); + if (lambda < hit.first) + hit = Hit(lambda, (ray.orig + lambda*ray.dir - center).unitise); + } +} + +class Group : Scene { + Sphere bound; + Scene[] children; + //mixin This!("bound, children"); + this (Sphere s, Scene[] c) + { + bound = s; + children = c; + } + void intersect(ref Hit hit, ref Ray ray) { + auto l = bound.ray_sphere(ray); + if (l < hit.first) foreach (child; children) child.intersect(hit, ray); + } +} + +double ray_trace(ref Vec light, ref Ray ray, Scene s) { + auto hit=Hit(double.infinity, Vec(0, 0, 0)); + s.intersect(hit, ray); + if (hit.first == double.infinity) return 0.0; + auto g = hit.second.dot(light); + if (g >= 0) return 0.0; + auto p = ray.orig + ray.dir*hit.first + hit.second*delta; + auto hit2=Hit(double.infinity, Vec(0, 0, 0)); + s.intersect(hit2, Ray(p, light*-1.0)); + return (hit2.first < double.infinity ? 0 : -g); +} + +Scene create(int level, ref Vec c, double r) { + auto s = new Sphere(c, r); + if (level == 1) return s; + Scene[] children=[s]; + double rn = 3*r/sqrt(12.0); + for (int dz=-1; dz<=1; dz+=2) + for (int dx=-1; dx<=1; dx+=2) + children~=create(level-1, c + Vec(dx, 1, dz)*rn, r/2); + return new Group(new Sphere(c, 3*r), children); +} + +void main(string[] args) { + int level = (args.length==3 ? args[1].atoi() : 9), + n = (args.length==3 ? args[2].atoi() : 512), ss = 4; + auto light = Vec(-1, -3, 2).unitise(); + auto s=create(level, Vec(0, -1, 0), 1); + printf("P5\n%d %d\n255", n, n); + for (int y=n-1; y>=0; --y) + for (int x=0; x<n; ++x) { + double g=0; + for (int d=0; d<ss*ss; ++d) { + auto dir=Vec(x+(d%ss)*1.0/ss-n/2.0, y+(d/ss)*1.0/ss-n/2.0, n).unitise(); + g += ray_trace(light, Ray(Vec(0, 0, -4), dir), s); + } + printf("%c", cast(ubyte)(0.5 + 255.0 * g / (ss*ss))); + } +}