FAQ Database Discussion Community

## Rotate Point3D around Unit Vector, Solved

c#,wpf,rotation,quaternions
as an Image above i want to rotate the point P1 around unit vector RotationAxis (Red vector in Image and its in Center). in my program (WPF) i Have a Quaternion and a 3DPoint. How can i rotate the Point P1? i tried Matrix rotation but it rotates nothing. Matrix3D...

## Quaternion based camera

opengl,graphics,3d,directx,quaternions
I try to implement an FPS camera based on quaternion math. I store a rotation quaternion variable called _quat and multiply it by another quaternion when needed. Here's some code: void Camera::SetOrientation(float rightAngle, float upAngle)//in degrees { glm::quat q = glm::angleAxis(glm::radians(-upAngle), glm::vec3(1,0,0)); q*= glm::angleAxis(glm::radians(rightAngle), glm::vec3(0,1,0)); _quat = q; } void...

## How to synchronize the position of two points with the same orientation represented in quaternion?

translate,quaternions
I have two points with fixed distance (e.g. 30 centimeter) and exactly the same orientation in 3D space. The position of point 1 (x1,y1,z1) and orientation of point 1 (represented in quaternion q0, q1, q2, q3) are already known. How can I calculate the position of point 2 ? (No...

## Quaternion product is different from the quaternion extracted from the matrix product

three.js,quaternions
Yesterday I have been trying to solve the following problem: calculate the local rotation quaternion for a bone given its global rotation quaternion and the skeleton state. I figured that the global quaternion equals to the parent bone global multiplied by the bone's local quaternion: global = globalParent * local...

## rotation matrix to quaternion (and back) what is wrong?

c++,quaternions,jmonkeyengine
I copied a code for conversion of 3D roation matrix to quaternions and back. The same code is used in jMonkey (I just rewrote it into my C++ class). However, it does not work properly (at least not as I would expect.) e.g. I made this test: matrix (a,b,c): a...

## How to rotate objects in OpenGL relative to local or global axes

c#,opengl,quaternions,rotational-matrices,sharpgl
I'm asking a question that has been asked a million times before, but I still haven't found a good answer after going through these and also resorting to other sites: How to rotate a graphic over global axes, and not to local axes? rotating objects in opengl How to rotate...

## Quaternion Rotation Between Two Sets of Vectors

c++,vector,rotation,quaternions
I would like some help on finding the rotation between two sets of two vectors in 3D as a quaternion. In each pair, the vectors would be at right angles to each other and have unit length (basically two vectors in an orthonormal basis). My current code looks something like...

## Applying a “Spread” value to an XMFLOAT4X4

rotation,directx-11,matrix-multiplication,quaternions
I'm attempting to add a small value to a World Matrix in order to replicate the accuracy of a fired weapon [pistol, assault rifle] Currently, my World Matrix resides at a Parent Objects' position, with the ability to rotate about the Y axis exclusively. I've done this in Unity3D, running...

## Kalman filter - quaternions - angle sensor

c,matlab,vector,accelerometer,quaternions
Kalman filters and quaternions are something new for me. I have a sensor which output voltage on its pins changes in function of its inclination on x,y and/or z-axis, i.e. an angle sensor. My questions: Is it possible to apply a Kalman filter to smooth the results and avoid any...

## Custom C++ Quaternion Rotation Not Working Correctly

c++,rotation,vector-graphics,quaternions
In my code, I have a quaternion that is used for rotation for a camera for the player. Rotation itself seems to work fine, but my directional vectors for moving and to rotate on do not rotate correctly. Quaternion Multiplication: Quaternion Quaternion::operator*(Vector3 other) const { float x_ = w *...

## Fast Quaternion-Vector Multiplication with other Transformation Matrices

math,matrix,3d,quaternions,rotational-matrices
I am currently trying to find an equivalent for the following equation: vec_res = inverse(VM) * (q * (VM * vec_input) * conjugate(q)) where VM is a standard view matrix , q is a normalized quaternion, and vec_input a vector. In the form: vec_res = A * vec_input; or vec_res...

## Is there a way to convert a quaternion to angles?

c++,matrix,directx,quaternions,directxmath
I have a (world) matrix, and it applies translation, rotation and scale into an 3D object. It is created with the function XMMatrixTransformation (DirectXMath) and the parameter RotationQuaternion is made by a call to XMQuaternionRotationRollPitchYaw. Then it is stored in a file along with other data. Then I need to...

## Difference Between Combining Quaternion Rotations and Rotation Matrices

matrix,rotation,quaternions
Is the result of combining two quaternion rotations the same as that of two matrices and then converting that into a quaternion? I have a quaternion (q1) and rotation matrix (m2) as input for a function (unfortunately non-negotiable) and would like to rotate the initial quaternion by the matrix resulting...

## Orienting an object based on a parent with quaternions?

c++,quaternions
I have 2 objects in 3D space, A & B, and object B is parented to A. Both objects have 3D positions, as well as a Quaternion representing their specific orientations. I have translation working fine, so whenever A moves, B moves. However, I can't seem to get the orientation...

## Calculating rotation delta between two quaternions (as another quaterion)

math,quaternions
I have some initial rotation r0 represented by quaternion and some actual rotation r (also an quaternion). I would like to get the quaternion that represents the delta of rotation. E.g. if r0 stands for 30st OX rotation and r is 50st OX, the rDelta should contain quaternion that represents...

## Rotate a 3D object on 3 axis in JavaFX properly

java,javafx,3d,quaternions,javafx-3d
So the method that I've used so far to rotate objects in JavaFX was that I layered it in 3 groups, each of them with a Rotate attached and locked to a single axis like so: Rotate heading, roll, pitch; Group normalrotate, rollrotate, verticalrotate; heading.setAxis(new Point3D(0,1,0)); normalrotate.getTransforms().add(heading); roll.setAxis(new Point3D(0,0,1)); rollrotate.getTransforms().add(roll);...

## Add 90 degrees to a Quaternion in Away3d

actionscript-3,math,quaternions,away3d
I'm attempting to rotate a Quaternion up 90 degrees on the Y axis in Away3d. I'm using an ANE to get Quaternion values from device motion, to set the camera view. This rotates the angle up, qu.fromAxisAngle(Vector3D.X_AXIS,Math.PI/2); q.multiply(q, qu ); But then seems to switch the other angles, i.e. now...

## Transformation Hierarchy - applying a parent's orientation to its children

c++,opengl,vector,transformation,quaternions
My goal: When being rendered, a child object needs to render relative to its parent; thus its own position and orientation need to be relative to its parent My problem: Translations work, but the parent's rotation/orientation isn't correctly being added to a child's transformation calculation; the child rotates on its...

## Quaternion to EulerXYZ, how to differentiate the negative and positive quaternion

c++,geometry,quaternions,euler-angles
I've been trying to figure out the difference between these, and why ToEulerXYZ does not get the right rotation. Using MathGeoLib: axisX: x 0.80878228 float y -0.58810818 float z 0.00000000 float axisY: x 0.58811820 float y 0.80877501 float z 0.00000000 float axisZ: x 0.00000000 float y 0.00000000 float z 1.0000000...

## Keep a relative position using quaternion orientation

math,quaternions
Let's say I have an object (A) with a position stored as a 3-number vector, and an orientation stored as a quaternion. I have a second object (B) with the same information. Object B is, for whatever reason, suddenly welded to object A. It is now stuck, and should perfectly...