3D Vector Field Plot [closed] - c++

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 6 years ago.
Improve this question
I am creating an Electromagnetic field simulator and I am using Qt3D to plot cuboids.The output should be the same input cuboid but with different color distribution indicating the magnetic field at each point but I can't figure how to plot it this way with various colors.
Input (2 intersecting cuboids):
Output should be similar to this:

Related

How to rotate an QGraphicsPixmapItem in Qt [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 2 years ago.
Improve this question
I am trying to rotate an image in Qt. If you try this game, you can easily see how the arrow is rotating:
https://www.friv.com/z/games/killcovid19/game.html?Desktop-x-x-w-x-x-xx
Assuming my image is in a QGraphicsPixmapItem, how should I make it rotate?
First, you need to set the rotation point (bottom-right/left in your case)
void QGraphicsItem::setTransformOriginPoint(qreal x, qreal y)
And then perform a rotation around the transform point
void QGraphicsItem::setRotation(qreal angle)

Histogram calculation for rotation invariant local binary pattern in opencv c++ [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 4 years ago.
Improve this question
I have been working on a opencv project that requires calculation of histogram for rotation invariant local binary pattern.I checked github and bytefish git repos but cant find what i am looking for.
Exactly what i want to say is that once i find the lbp image of any video frame or image, how to make it rotation invariant lbp and find its histogram as texture feature that can be further used for training or classification.
Can someone tell me how to exactly find the histogram for rotation invariant LBP and histogram for uniform rotation invariant LBP in opencv c++.
Thankyou!

Detect High density pixel areas in a binary image [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 6 years ago.
Improve this question
I am doing background subtraction, and I obtain a binary image with foreground objects and with some noise.
I want to obtain a ROI for each object on the binary image and them analyze it to ensure that is the object that I want.
How do I segment only the areas with high pixel intensity (objects)?
One example of obtained image:
Have a look at openCv simpleBlobDetector, there are several configurable parameters to it and tons of tutorials online.
The documentation can be found here: http://docs.opencv.org/trunk/d0/d7a/classcv_1_1SimpleBlobDetector.html
Alternatively you could just convolve a white rectangle across multiple scale spaces and return the median values over each scale space.

Calculate The object angle(face) having two points? [closed]

Closed. This question needs to be more focused. It is not currently accepting answers.
Want to improve this question? Update the question so it focuses on one problem only by editing this post.
Closed 7 years ago.
Improve this question
C++, I want calculate the angle of the direction of the two points.
Here is a picture which shows the two points and the direction of how to get the angle of the direction?
p1 - start point. p2 - direction point. me need direction angle(facing?) from p1 to p2
#include <cmath>
// ...
double angle = atan2(p2.y - p1.y, p2.x - p1.x);
// ...
If you want to, you can also make sure that p1 != p2, because if it is then you'll get a domain error.

How can I map multiple images on the sphere with C++/OpenGL? [closed]

Closed. This question needs details or clarity. It is not currently accepting answers.
Want to improve this question? Add details and clarify the problem by editing this post.
Closed 2 years ago.
Improve this question
Is there anyone know how to map multiple images on the sphere using C++/OpenGL?
As the picture here;
images on sphere
You can split the sphere in multiple sections, each one having bound a single image.
It should be reltively easy to generate a sphere slice coordinate using sphere equation.
You could just combine all the images into a single texture using an image editing program. Then you would only have to apply a single texture over the entire sphere. To do this you would just need to find a way to import a model of a sphere into your program. (Unless you want to try generating one procedurally.)
The easiest way is creating texture images with alpha channel.
You can add many texture into shader code and blend them all by alpha as masking.