1 files changed, 105 insertions, 0 deletions
diff --git a/src/vec3.cpp b/src/vec3.cpp
new file mode 100644
index 0000000..bf0b021
--- /dev/null
+++ b/src/vec3.cpp
@@ -0,0 +1,105 @@
+/* copy-pasted from:
+ * https://www.programming-techniques.com/2013/05/basic-euclidean-vector-operations-in-c.htm
+ */
+
+#include <iostream>
+#include <cmath>
+#include <fml/quat.h>
+using std::ostream;
+using namespace fml;
+
+namespace fml{
+    vec3::vec3() {
+        v[0] = 0;
+        v[1] = 0;
+        v[2] = 0;
+    }
+    vec3::vec3(scalar x) {
+        v[0] = x;
+        v[1] = 0;
+        v[2] = 0;
+    }
+    vec3::vec3(scalar x, scalar y, scalar z) {
+        v[0] = x;
+        v[1] = y;
+        v[2] = z;
+    }
+    scalar &vec3::operator[](int index) {
+        return v[index];
+    }
+    scalar vec3::operator[](int index) const {
+        return v[index];
+    }
+    vec3 vec3::operator*(scalar scale) const {
+        return vec3(v[0] * scale, v[1] * scale, v[2] * scale);
+    }
+    vec3 vec3::operator/(scalar scale) const {
+        return vec3(v[0] / scale, v[1] / scale, v[2] / scale);
+    }
+    vec3 vec3::operator+(const vec3 &other)  const{
+        return vec3(v[0] + other.v[0], v[1] + other.v[1], v[2] + other.v[2]);
+    }
+    vec3 vec3::operator-(const vec3 &other) const {
+        return vec3(v[0] - other.v[0], v[1] - other.v[1], v[2] - other.v[2]);
+    }
+    vec3 vec3::operator-() const {
+        return vec3(-v[0], -v[1], -v[2]);
+    }
+    const vec3 &vec3::operator*=(scalar scale) {
+        v[0] *= scale;
+        v[1] *= scale;
+        v[2] *= scale;
+        return *this;
+    }
+    const vec3 &vec3::operator/=(scalar scale) {
+        v[0] /= scale;
+        v[1] /= scale;
+        v[2] /= scale;
+        return *this;
+    }
+    const vec3 &vec3::operator+=(const vec3 &other) {
+        v[0] += other.v[0];
+        v[1] += other.v[1];
+        v[2] += other.v[2];
+        return *this;
+    }
+    const vec3 &vec3::operator-=(const vec3 &other) {
+        v[0] -= other.v[0];
+        v[1] -= other.v[1];
+        v[2] -= other.v[2];
+        return *this;
+    }
+    scalar vec3::magnitude() const {
+        return sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
+    }
+    scalar vec3::magnitudeSquared() const {
+        return v[0] * v[0] + v[1] * v[1] + v[2] * v[2];
+    }
+    vec3 vec3::normalize() const {
+        scalar m = sqrt(v[0] * v[0] + v[1] * v[1] + v[2] * v[2]);
+        return vec3(v[0] / m, v[1] / m, v[2] / m);
+    }
+    scalar vec3::dot(const vec3 &other) const {
+        return v[0] * other.v[0] + v[1] * other.v[1] + v[2] * other.v[2];
+    }
+    vec3 vec3::cross(const vec3 &other) const {
+        return vec3(v[1] * other.v[2] - v[2] * other.v[1],
+                    v[2] * other.v[0] - v[0] * other.v[2],
+                    v[0] * other.v[1] - v[1] * other.v[0]);
+    }
+    std::ostream &operator<<(std::ostream &output, const vec3 &v) {
+        return output << v[0] << " " << v[1] << " " << v[2];
+    }
+
+    std::istream &operator>>(std::istream &input, vec3 &v)
+    {
+        if(!(input >> v[0] >> v[1] >> v[2]))
+            throw "error parsing vector";
+        return input;
+    }
+
+    vec3 operator*(scalar scale, const vec3 &v)
+    {
+        return v * scale;
+    }
+}