Compare commits

..

No commits in common. "9f4868917d86fd836f96fa081067be5602399a78" and "b2265d26a323c2457c065848ff846e3a9b512c7b" have entirely different histories.

2 changed files with 1 additions and 12 deletions

2
vec3.h
View File

@ -89,7 +89,7 @@ inline Vec3 operator/(const Vec3& v, double t) {
inline double dot(const Vec3 &u, const Vec3& v) { inline double dot(const Vec3 &u, const Vec3& v) {
return u.e[0] * v.e[0] return u.e[0] * v.e[0]
+ u.e[1] * v.e[1] + u.e[1] * v.e[1]
+ u.e[2] * v.e[2]; + u.e[2] * v.e[1];
} }
inline Vec3 cross(const Vec3 &u, const Vec3& v) { inline Vec3 cross(const Vec3 &u, const Vec3& v) {

View File

@ -4,18 +4,7 @@
#include "vec3.h" #include "vec3.h"
#include "ray.h" #include "ray.h"
bool hit_sphere(const Point3& center, double radius, const Ray& r) {
Vec3 oc = r.origin() - center;
auto a = dot(r.direction(), r.direction());
auto b = 2.0 * dot(oc, r.direction());
auto c = dot(oc, oc) - radius * radius;
auto disciminant = b*b - 4*a*c;
return disciminant > 0;
}
Color ray_color(const Ray& r) { Color ray_color(const Ray& r) {
if (hit_sphere(Point3(0, 0, -1), 0.5, r))
return Color(1, 0, 0);
Vec3 unit_direction = unit_vector(r.direction()); Vec3 unit_direction = unit_vector(r.direction());
auto t = 0.5 * (unit_direction.y() + 1.0); auto t = 0.5 * (unit_direction.y() + 1.0);
return (1.0 - t) * Color(1.0, 1.0, 1.0) + t * Color(0.5, 0.7, 1.0); return (1.0 - t) * Color(1.0, 1.0, 1.0) + t * Color(0.5, 0.7, 1.0);