Mercurial > projects > ldc
view demos/ray.d @ 650:aa6a0b7968f7
Added test case for bug #100
Removed dubious check for not emitting static private global in other modules without access. This should be handled properly somewhere else, it's causing unresolved global errors for stuff that should work (in MiniD)
author | Tomas Lindquist Olsen <tomas.l.olsen@gmail.com> |
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date | Sun, 05 Oct 2008 17:28:15 +0200 |
parents | 718ddecc053c |
children | eef8ac26c66c |
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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(LLVMDC) { 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))); } }