#define BLANK_MODEL_GEOMETRY_H_
#include <algorithm>
+#include <limits>
#include <glm/glm.hpp>
constexpr float PI_1p5 = PI * 1.5f;
constexpr float PI_2p0 = PI * 2.0f;
+constexpr float PI_inv = 1.0f / PI;
+constexpr float PI_0p5_inv = 1.0f / PI_0p5;
+
+constexpr float DEG_RAD_FACTOR = PI / 180.0f;
+constexpr float RAD_DEG_FACTOR = 180.0f / PI;
+
+constexpr float deg2rad(float d) noexcept {
+ return d * DEG_RAD_FACTOR;
+}
+
+constexpr float rad2deg(float r) noexcept {
+ return r * RAD_DEG_FACTOR;
+}
+
+
+inline float length_squared(const glm::vec3 &v) noexcept {
+ return dot(v, v);
+}
+
+inline float distance_squared(const glm::vec3 &a, const glm::vec3 &b) noexcept {
+ return length_squared(a - b);
+}
+
+
+template <class T>
+inline bool iszero(const T &v) noexcept {
+ return length_squared(v) < std::numeric_limits<typename T::value_type>::epsilon();
+}
+
+
+template<class T>
+T manhattan_distance(const glm::tvec3<T> &a, const glm::tvec3<T> &b) noexcept {
+ glm::tvec3<T> diff(abs(a - b));
+ return diff.x + diff.y + diff.z;
+}
+
+template<class T>
+T manhattan_radius(const glm::tvec3<T> &v) noexcept {
+ glm::tvec3<T> a(abs(v));
+ return std::max(a.x, std::max(a.y, a.z));
+}
+
+
struct AABB {
glm::vec3 min;
glm::vec3 max;