rayzor

annotate src/raytrace.cc @ 19:252999cd1a3f

added reflection and refraction
author John Tsiombikas <nuclear@member.fsf.org>
date Tue, 15 Apr 2014 00:59:37 +0300
parents 79609d482762
children 5380ff64e83f
rev   line source
nuclear@17 1 #include <assert.h>
nuclear@17 2 #include <float.h>
nuclear@17 3 #include "raytrace.h"
nuclear@17 4 #include "rayzor.h"
nuclear@17 5 #include "scene.h"
nuclear@17 6 #include "logger.h"
nuclear@17 7
nuclear@17 8 Vector3 ray_trace(const Ray &ray, int iter)
nuclear@17 9 {
nuclear@17 10 RayHit hit;
nuclear@17 11 if(!scene->intersect(ray, &hit)) {
nuclear@17 12 return scene->get_background(ray);
nuclear@17 13 }
nuclear@17 14
nuclear@17 15 return shade(hit, iter);
nuclear@17 16 }
nuclear@17 17
nuclear@17 18 static inline float positive(float x)
nuclear@17 19 {
nuclear@17 20 return x < 0.0f ? 0.0f : x;
nuclear@17 21 }
nuclear@17 22
nuclear@17 23 Vector3 shade(const RayHit &hit, int iter)
nuclear@17 24 {
nuclear@19 25 const Material &mtl = hit.obj->mtl;
nuclear@19 26
nuclear@17 27 Vector3 pos = hit.ray.origin + hit.ray.dir * hit.dist;
nuclear@17 28 Vector3 norm = hit.obj->hit_normal(hit);
nuclear@17 29 norm = normalize(transform(normal_matrix(hit.obj->get_matrix()), norm));
nuclear@17 30 Vector3 vdir = -normalize(hit.ray.dir);
nuclear@17 31
nuclear@19 32 float ior = mtl.ior;
nuclear@19 33
nuclear@19 34 if(dot(norm, hit.ray.dir) > 0.0) {
nuclear@19 35 norm = -norm;
nuclear@19 36 ior = 1.0 / mtl.ior;
nuclear@19 37 }
nuclear@19 38
nuclear@17 39 Vector3 color = scene->get_ambient();
nuclear@17 40
nuclear@19 41 // for each light, calculate local illumination
nuclear@17 42 int num_lights = scene->get_light_count();
nuclear@17 43 for(int i=0; i<num_lights; i++) {
nuclear@17 44 const Light *lt = scene->get_light(i);
nuclear@17 45 Vector3 ldir = lt->get_position() - pos;
nuclear@17 46 Vector3 lcol = lt->get_color(pos);
nuclear@17 47
nuclear@17 48 RayHit hit;
nuclear@17 49 if(!scene->intersect(Ray(pos, ldir), &hit) || hit.dist > 1.0) {
nuclear@17 50 // if we can see the light, calculate and add its contribution
nuclear@17 51 ldir.normalize();
nuclear@17 52 float ndotl = positive(dot(norm, ldir));
nuclear@19 53 Vector3 diffuse = mtl.diffuse * lcol * ndotl;
nuclear@17 54
nuclear@17 55 Vector3 hdir = normalize(ldir + vdir);
nuclear@17 56 float ndoth = positive(dot(norm, hdir));
nuclear@19 57 Vector3 specular = mtl.specular * lcol * pow(ndoth, mtl.roughness * 128.0);
nuclear@17 58
nuclear@19 59 color = color + lerp(specular, diffuse, mtl.roughness);
nuclear@17 60 }
nuclear@17 61 }
nuclear@17 62
nuclear@19 63 if(mtl.reflect > 1e-4 && iter < 6) {
nuclear@19 64 Ray reflray(pos, reflect(vdir, norm));
nuclear@19 65
nuclear@19 66 Vector3 rcol = ray_trace(reflray, iter + 1) * mtl.specular * mtl.reflect;
nuclear@19 67 color = color + rcol;
nuclear@19 68 }
nuclear@19 69
nuclear@19 70 if(mtl.refract > 1e-4 && iter < 6) {
nuclear@19 71 Ray refrray(pos, refract(vdir, norm, ior));
nuclear@19 72
nuclear@19 73 Vector3 rcol = ray_trace(refrray, iter + 1) * mtl.specular * mtl.refract;
nuclear@19 74 color = color + rcol;
nuclear@19 75 }
nuclear@19 76
nuclear@17 77 return color;
nuclear@17 78 }