Mercurial > projects > ldc
view demos/ray.d @ 1064:f0b6549055ab
Make LDC work with LLVM trunk (s/LinkOnceLinkage/LinkOnceOdrLinkage/)
Also moved the #defines for linkage types into a separate header instead of
mars.h so we can #include revisions.h without having to rebuild the entire
frontend every time we update.
(I'm using revisions.h to get the LLVM revision for use in preprocessor
conditionals. It should work with LLVM release 2.5, old trunk and new trunk)
author | Frits van Bommel <fvbommel wxs.nl> |
---|---|
date | Sun, 08 Mar 2009 16:13:10 +0100 |
parents | eef8ac26c66c |
children |
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import tango.stdc.stdio; alias char[] string; 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; } version(LDC) { pragma(intrinsic, "llvm.sqrt.f64") double sqrt(double val); } else { import tango.stdc.math; } 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; 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,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))); } }