Mercurial > projects > ldc
view demos/ray.d @ 109:5ab8e92611f9 trunk
[svn r113] Added initial support for associative arrays (AAs).
Fixed some problems with the string runtime support functions.
Fixed initialization of array of structs.
Fixed slice assignment where LHS is slice but RHS is dynamic array.
Fixed problems with result of assignment expressions.
Fixed foreach problems with key type mismatches.
author | lindquist |
---|---|
date | Wed, 21 Nov 2007 04:13:15 +0100 |
parents | 5071469303d4 |
children | 9922b9982552 |
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import std.stdio; 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; 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); writefln("P5\n", n, " ", n, "\n255"); 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))); } }