Blueprint rotations go through Rotator. That is where gimbal lock comes from.
Unreal Engine exposes only a small part of quaternion math to Blueprints. Operations such as the shortest rotation between two directions, swing-and-twist decomposition, angular distance and interpolation without unwanted flipping normally require conversions through Rotator or custom C++.
Blueprint Quaternion adds 85 pure Blueprint nodes under Math > Quaternion. It covers the operations available for Rotators, plus the operations that only quaternions can express.
Interpolate rotations
Slerp and normalized Lerp, with shortest-path control.
Ease with the easing curves used by other Blueprint math nodes.
Interp To and Interp To Constant for frame-by-frame tracking.
Rotate Towards with a maximum angular step.
Squad and Calc Tangent for smooth paths through rotation keys.
Fixed and dynamic weighted moving averages for noisy rotation input.
Build and decompose rotations
Create quaternions from axis and angle, Euler angles, roll/pitch/yaw, rotation vectors, axes, look-at targets and the shortest arc between vectors or normals.
Split a rotation into swing and twist for joint limits, aim offsets and controlled twisting.
Read the twist angle, rotation angle and rotation axis.
Measure angular distance between two orientations in degrees.
Use Log and Exp for quaternion scaling and averaging.
Apply, combine and convert
Rotate or unrotate vectors and read forward, right and up axes.
Compose rotations, calculate a delta, invert a rotation or scale its angle.
Make and break transforms without converting the rotation through Rotator.
Convert between Quaternion, Rotator, Euler angles, rotation vectors, Transform, Matrix, Vector and String.
Generate random rotations, including uniform, seeded and cone-limited variants.
Inspect, normalize, compare and select rotations, or work directly with X, Y, Z and W components.
Edit quaternion properties comfortably
The FQuat details row shows Euler angles in the header, axis and angle below, and raw X, Y, Z and W components in a separate group. It supports multiple selected objects, draggable values and pasted rotation text.
The customization can be disabled per user in Editor Preferences > Plugins > Blueprint Quaternion, restoring the engine's row immediately without restarting the editor.
Consistent behaviour
Every angle pin uses degrees.
Nodes that treat a quaternion as a rotation normalize their inputs and outputs.
Zero-length and non-finite rotation inputs fall back to Identity instead of propagating invalid values.
Nearly Equal compares orientations, so a quaternion and its negation are treated as the same rotation.
Compose Quaternions applies B first, then A, matching Unreal Engine's quaternion multiplication.
The library is BlueprintThreadSafe and can be used in thread-safe Animation Blueprint updates.
There are no actors to place, systems to initialize or runtime settings to configure. Enable the plugin and use the nodes directly in your Blueprint graphs. Full C++ source is included.
Documentation: Blueprint Quaternion documentation