1 files changed, 36 insertions, 0 deletions
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+//
+// Created by Keuin on 2022/4/11.
+//
+
+#ifndef RT_RAY_H
+#define RT_RAY_H
+
+#include "vec.h"
+
+// A ray is a half-line, starts from a 3d point, along the direction of a unit vector, to the infinity
+template<typename T>
+class ray3 {
+    const vec3<T> source_;
+    const vec3<T> direction_; // unit vector
+
+public:
+    ray3() = delete;
+    ray3(const vec3<T> &source, const vec3<T> &direction) : source_(source), direction_(direction.unit_vec()) {}
+
+    vec3<T> source() const {
+        return source_;
+    }
+
+    vec3<T> direction() const {
+        return direction_;
+    }
+
+    template<typename U>
+    vec3<T> at(U t) const {
+        return source_ + direction_ * t;
+    }
+};
+
+using ray3d = ray3<double>;
+
+#endif //RT_RAY_H