qnode | Client node of LwM2M-like Lightweight Message

In appointmentFunctions.h you include queueFunctions.h

So when queueFunctions.h is read the type Appointment is unknown.

It doesn't help you that queueFunctions.h also includes appointmentFunctions.h because at that time appointmentFunctions_H__ is already defined, i.e. the file content will not be read.

If file X.h depends on something from file Y.h and at the same time Y.h depends on something from file X.h you have a design error that must be fixed.

As far as I can see the dependency is only pointer to struct so you can get rid of the dependency by forward declaring the struct.

In queueFunctions.h do these changes:

You could have a field called prev in your class QNode to track the previous node it visited and when you finished the search, you can track your path by following the prev link.

The code would be :

First, the method creates a new node with the given key, then it checks if the rear is empty (which actually means that the queue is empty). If the queue is empty, it sets the new node with the key as the rear and the front since it's the only node in the list. If the list isn't empty, it links the node to the rear (this.rear.next==temp) and updates it as the new rear.

As for your question about the front, it doesn't need to be updated when you use enqueue. Enqueue adds a node to the end of the list and updates it as the rear. Dequeue removes a node from the front and updates the new front (the one after the original front).

There is already a C++ translation this QML code that I tried to translate (using geometry shader):

https://github.com/ismailsunni/qt3d-custom-shader

My own translation can be found here. It works now after solving the issues mentioned in this question.

I got a different version running based on this bug report. You can find my implementation on GitHub. The billboards don't change their size when the camera moves, i.e. become smaller and larger on screen like every other object, but I hope you can work with that.

On the master branch the images also move for some reason as can be seen in this image:

The no_instanced_rendering branch doesn't use instanced rendering and displays everything correctly.

Edit I'm sorry I'm not using your example but I don't have time anymore to adjust it. Check out the patch related to the bug report I mentioned. The person implemented a material with this effect, you should be able to extract it and make it run.

GitHub users wonder-sk and ismailsunni solved this issue for me by pointing to an error in the code:

QTextureMaterial doesn't support transparency in the textures.

Check out my answer to this question to see how to implement transparency in textures yourself. There is not out-of-the-box solution in Qt3D.

The solution is that the python package "pennylane" doesn't yet have the resources built out to work on GPUs. Since Pennylane is a relatively new package, this is something they plan to build out in the future.

The problem is in your release implementation:

The rule is one free per malloc, since you are not allocating space for your temporary node (is just a pointer to the front), you dont have to call free, just ignore it.