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Diffstat (limited to 'src/include/glm/gtx/quaternion.inl')
| -rw-r--r-- | src/include/glm/gtx/quaternion.inl | 159 |
1 files changed, 159 insertions, 0 deletions
diff --git a/src/include/glm/gtx/quaternion.inl b/src/include/glm/gtx/quaternion.inl new file mode 100644 index 0000000..34aed89 --- /dev/null +++ b/src/include/glm/gtx/quaternion.inl @@ -0,0 +1,159 @@ +/// @ref gtx_quaternion
+
+#include <limits>
+#include "../gtc/constants.hpp"
+
+namespace glm
+{
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER GLM_CONSTEXPR qua<T, Q> quat_identity()
+ {
+ return qua<T, Q>(static_cast<T>(1), static_cast<T>(0), static_cast<T>(0), static_cast<T>(0));
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER vec<3, T, Q> cross(vec<3, T, Q> const& v, qua<T, Q> const& q)
+ {
+ return inverse(q) * v;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER vec<3, T, Q> cross(qua<T, Q> const& q, vec<3, T, Q> const& v)
+ {
+ return q * v;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER qua<T, Q> squad
+ (
+ qua<T, Q> const& q1,
+ qua<T, Q> const& q2,
+ qua<T, Q> const& s1,
+ qua<T, Q> const& s2,
+ T const& h)
+ {
+ return mix(mix(q1, q2, h), mix(s1, s2, h), static_cast<T>(2) * (static_cast<T>(1) - h) * h);
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER qua<T, Q> intermediate
+ (
+ qua<T, Q> const& prev,
+ qua<T, Q> const& curr,
+ qua<T, Q> const& next
+ )
+ {
+ qua<T, Q> invQuat = inverse(curr);
+ return exp((log(next * invQuat) + log(prev * invQuat)) / static_cast<T>(-4)) * curr;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER vec<3, T, Q> rotate(qua<T, Q> const& q, vec<3, T, Q> const& v)
+ {
+ return q * v;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER vec<4, T, Q> rotate(qua<T, Q> const& q, vec<4, T, Q> const& v)
+ {
+ return q * v;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER T extractRealComponent(qua<T, Q> const& q)
+ {
+ T w = static_cast<T>(1) - q.x * q.x - q.y * q.y - q.z * q.z;
+ if(w < T(0))
+ return T(0);
+ else
+ return -sqrt(w);
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER GLM_CONSTEXPR T length2(qua<T, Q> const& q)
+ {
+ return q.x * q.x + q.y * q.y + q.z * q.z + q.w * q.w;
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER qua<T, Q> shortMix(qua<T, Q> const& x, qua<T, Q> const& y, T const& a)
+ {
+ if(a <= static_cast<T>(0)) return x;
+ if(a >= static_cast<T>(1)) return y;
+
+ T fCos = dot(x, y);
+ qua<T, Q> y2(y); //BUG!!! qua<T> y2;
+ if(fCos < static_cast<T>(0))
+ {
+ y2 = -y;
+ fCos = -fCos;
+ }
+
+ //if(fCos > 1.0f) // problem
+ T k0, k1;
+ if(fCos > (static_cast<T>(1) - epsilon<T>()))
+ {
+ k0 = static_cast<T>(1) - a;
+ k1 = static_cast<T>(0) + a; //BUG!!! 1.0f + a;
+ }
+ else
+ {
+ T fSin = sqrt(T(1) - fCos * fCos);
+ T fAngle = atan(fSin, fCos);
+ T fOneOverSin = static_cast<T>(1) / fSin;
+ k0 = sin((static_cast<T>(1) - a) * fAngle) * fOneOverSin;
+ k1 = sin((static_cast<T>(0) + a) * fAngle) * fOneOverSin;
+ }
+
+ return qua<T, Q>(
+ k0 * x.w + k1 * y2.w,
+ k0 * x.x + k1 * y2.x,
+ k0 * x.y + k1 * y2.y,
+ k0 * x.z + k1 * y2.z);
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER qua<T, Q> fastMix(qua<T, Q> const& x, qua<T, Q> const& y, T const& a)
+ {
+ return glm::normalize(x * (static_cast<T>(1) - a) + (y * a));
+ }
+
+ template<typename T, qualifier Q>
+ GLM_FUNC_QUALIFIER qua<T, Q> rotation(vec<3, T, Q> const& orig, vec<3, T, Q> const& dest)
+ {
+ T cosTheta = dot(orig, dest);
+ vec<3, T, Q> rotationAxis;
+
+ if(cosTheta >= static_cast<T>(1) - epsilon<T>()) {
+ // orig and dest point in the same direction
+ return quat_identity<T,Q>();
+ }
+
+ if(cosTheta < static_cast<T>(-1) + epsilon<T>())
+ {
+ // special case when vectors in opposite directions :
+ // there is no "ideal" rotation axis
+ // So guess one; any will do as long as it's perpendicular to start
+ // This implementation favors a rotation around the Up axis (Y),
+ // since it's often what you want to do.
+ rotationAxis = cross(vec<3, T, Q>(0, 0, 1), orig);
+ if(length2(rotationAxis) < epsilon<T>()) // bad luck, they were parallel, try again!
+ rotationAxis = cross(vec<3, T, Q>(1, 0, 0), orig);
+
+ rotationAxis = normalize(rotationAxis);
+ return angleAxis(pi<T>(), rotationAxis);
+ }
+
+ // Implementation from Stan Melax's Game Programming Gems 1 article
+ rotationAxis = cross(orig, dest);
+
+ T s = sqrt((T(1) + cosTheta) * static_cast<T>(2));
+ T invs = static_cast<T>(1) / s;
+
+ return qua<T, Q>(
+ s * static_cast<T>(0.5f),
+ rotationAxis.x * invs,
+ rotationAxis.y * invs,
+ rotationAxis.z * invs);
+ }
+}//namespace glm
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