empty cornell box

raytracer/aarect.h

@@ -25,6 +25,46 @@ class xy_rect : public hittable {
         double x0, x1, y0, y1, k;
 };
 
+class xz_rect : public hittable {
+    public:
+        xz_rect() {}
+
+        xz_rect(double _x0, double _x1, double _z0, double _z1, double _k, shared_ptr<material> mat) : x0(_x0), x1(_x1), z0(_z0), z1(_z1), k(_k), mp(mat) {};
+
+        virtual bool hit(const ray& r, double t_min, double t_max, hit_record& rec) const override;
+
+        virtual bool bounding_box(double time0, double time1, aabb& output_box) const override {
+            // The bounding box must have non-zero width in each dimension, so pad the Y
+            // dimension a small amount.
+            output_box = aabb(point3(x0, k-0.0001, z0), point3(x1, k+0.0001, z1));
+            return true;
+        }
+
+    public:
+        shared_ptr<material> mp;
+        double x0, x1, z0, z1, k;
+};
+
+class yz_rect : public hittable {
+    public:
+        yz_rect() {}
+
+        yz_rect(double _y0, double _y1, double _z0, double _z1, double _k, shared_ptr<material> mat) : y0(_y0), y1(_y1), z0(_z0), z1(_z1), k(_k), mp(mat) {};
+
+        virtual bool hit(const ray& r, double t_min, double t_max, hit_record& rec) const override;
+
+        virtual bool bounding_box(double time0, double time1, aabb& output_box) const override {
+            // The bounding box must have non-zero width in each dimension, so pad the X
+            // dimension a small amount.
+            output_box = aabb(point3(k-0.0001, y0, z0), point3(k+0.0001, y1, z1));
+            return true;
+        }
+
+    public:
+        shared_ptr<material> mp;
+        double y0, y1, z0, z1, k;
+};
+
 bool xy_rect::hit(const ray& r, double t_min, double t_max, hit_record& rec) const {
     auto t = (k - r.origin().z()) / r.direction().z();
 
@@ -49,5 +89,52 @@ bool xy_rect::hit(const ray& r, double t_min, double t_max, hit_record& rec) con
     return true;
 }
 
+bool xz_rect::hit(const ray& r, double t_min, double t_max, hit_record& rec) const {
+    auto t = (k - r.origin().y()) / r.direction().y();
+
+    if (t < t_min || t > t_max)
+        return false;
+
+    auto x = r.origin().x() + t*r.direction().x();
+    auto z = r.origin().z() + t*r.direction().z();
+
+    if (x < x0 || x > x1 || z < z0 || z > z1)
+        return false;
+
+    rec.u = (x-x0) / (x1-x0);
+    rec.v = (z-z0) / (z1-z0);
+    rec.t = t;
+
+    auto outward_normal = vec3(0, 1, 0);
+    rec.set_face_normal(r, outward_normal);
+    rec.mat_ptr = mp;
+    rec.p = r.at(t);
+
+    return true;
+}
+
+bool yz_rect::hit(const ray& r, double t_min, double t_max, hit_record& rec) const {
+    auto t = (k - r.origin().x()) / r.direction().x();
+
+    if (t < t_min || t > t_max)
+        return false;
+
+    auto y = r.origin().y() + t*r.direction().y();
+    auto z = r.origin().z() + t*r.direction().z();
+
+    if (y < y0 || y > y1 || z < z0 || z > z1)
+        return false;
+
+    rec.u = (y-y0) / (y1-y0);
+    rec.v = (z-z0) / (z1-z0);
+    rec.t = t;
+
+    auto outward_normal = vec3(1, 0, 0);
+    rec.set_face_normal(r, outward_normal);
+    rec.mat_ptr = mp;
+    rec.p = r.at(t);
+
+    return true;
+}
 
 #endif // AARECT_H

raytracer/main.cpp

@@ -131,13 +131,32 @@ hittable_list simple_light() {
     return objects;
 }
 
+hittable_list cornell_box() {
+    hittable_list objects;
+
+    auto red = make_shared<lambertian>(colour(.65, .05, .05));
+    auto white = make_shared<lambertian>(colour(.73, .73, .73));
+    auto green = make_shared<lambertian>(colour(.12, .45, .15));
+    auto light = make_shared<diffuse_light>(colour(15, 15, 15));
+
+    objects.add(make_shared<yz_rect>(0, 555, 0, 555, 555, green));
+    objects.add(make_shared<yz_rect>(0, 555, 0, 555, 0, red));
+    objects.add(make_shared<xz_rect>(213, 343, 227, 332, 554, light));
+    objects.add(make_shared<xz_rect>(0, 555, 0, 555, 0, white));
+    objects.add(make_shared<xz_rect>(0, 555, 0, 555, 555, white));
+    objects.add(make_shared<xy_rect>(0, 555, 0, 555, 555, white));
+
+    return objects;
+}
+
 int main() {
 
     // write output image in ppm
-    const auto aspect_ratio = 16.0 / 9.0;
-    const int image_width = 400;
+    const auto aspect_ratio = 1.0;
+    // const auto aspect_ratio = 16.0 / 9.0;
+    const int image_width = 600;
     const int image_height = static_cast<int>(image_width / aspect_ratio);
-    const int samples_per_pixel = 400;
+    const int samples_per_pixel = 200;
     const int max_depth = 50;
 
     // world
@@ -183,14 +202,22 @@ int main() {
             vfov = 20.0;
             break;
 
-        default:
         case 5:
             background = colour(0,0,0);
             world = simple_light();
             lookfrom = point3(26,3,6);
             lookat = point3(0,2,0);
             vfov = 20.0;
             break;
+
+        default:
+        case 6:
+            world = cornell_box();
+            background = colour(0,0,0);
+            lookfrom = point3(278, 278, -800);
+            lookat = point3(278, 278, 0);
+            vfov = 40.0;
+            break;
     }
 
     // camera with depth of field