Tagged Questions
0
votes
0answers
20 views
Transformation into cartesian coordinates
I need some help with specific transformations and rotations.
But first, I need to describe context.
Imagine two points in space situated at $(x_1,y_1,z_1)$ and $(x_2,y_2,z_2)$ respectively. In
a ...
1
vote
1answer
63 views
Find rotation that maps a point to its target
I have a 3D point that is rotated about the $x$-axis and after that about the $y$-axis. I know the result of this transformation. Is there an analytical way to compute the rotation angles?
$$
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4
votes
2answers
107 views
How to solve an overdetermined system of point mappings via rotation and translation
I have a set of points in one coordinate system $P_1, \ldots, P_n$ and their corresponding points in another coordinate system $Q_1, \ldots , Q_n$. All points are in $\mathbb{R}^3$.
I'm looking for a ...
0
votes
2answers
110 views
3D transformation between two polylines problem
Say I have 2 separate objects.
One is a line defined by two points, the other is a polyline defined by three points.
Line 1 consists of the set of two points:
$a=(0,0,0)$ and b=$(0,0,1)$
Line 2 ...
0
votes
1answer
105 views
Rotation matrix for a set of points
I've got a set of $N$ points $p_1,\dots,p_N$ that all belong to a real object. Consequently, there are $N-1$ vectors $\vec{v}_i$ when $\vec{v}_i$ points from $p_1$ to $p_i$.
Now, the object is ...
0
votes
0answers
221 views
rotation and converting between coordinate systems
Let's say you have coordinates 'a','b','c','d' in the coordinate system (x,y), and it needs to be transformed to coordinates 'e','f','g','h' in the coordinate system (x',y').
Example
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0
votes
0answers
130 views
Converting global coordinates into set of local matrices for ik skeleton creation
I have the 3d global positions of a set of joints as they move over time and the ik skeleton structure which relates them. I am currently writing some code to convert this information in .bvh file. I ...
3
votes
2answers
76 views
Put a transformation under the form of a rotation in the complex plane
On the complex plane, I have a transformation "T" such that :
$z' = (m+i)z + m - 1 - i$ ($z'$ is the image and $z$ the preimage, $z$ and $z'$ are both complex number)
and $m$ is a real number.
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2
votes
2answers
2k views
How do I rotate a matrix transformation with a centered origin?
This is actually something I'm doing in Objective-C programming, but since it's very math-oriented I thought I'd post it here.
I was reading up on linear transformations: ...
0
votes
1answer
87 views
2D transformation without rotation
Is there a name for 2D transformation with the least squares adjustment having the following parameters:
shift_x,
shift_y,
scale.
Transformation does not use any rotation... Thanks for your help.
1
vote
1answer
190 views
correct rotation and translation matrices
I wrote a C++ program that can calculate the magnetic field $\bar{B}$ generated by a circular coil that is placed in the origin, for a given point $\bar{P}$ in 3D ...
0
votes
1answer
437 views
how to perform a rotation around a point which itself is rotating?
I'm working on rotating human limbs in a 3d game. I use Linear Algebra matrix rotations and translations to achieve moving the human and limbs. I currently can rotate around a pivot point by first ...
