I want to show a car's path in a window in real time, how to do that, and what classes I have to use. Is there anything like drawing area, in Qt.
Any Help will be appreciated.
You'll need to read up on QGraphicsview. There are several helpful examples that show every bit of what functionality is present here. The implementation itself... I guess it's just a bunch of QLines on a QGraphicsScene. The realtime part is handled by calling repaint or paintevent or whatever it's called periodically, or setting up a complex animation.
The Qwt library on top of Qt is pretty good for this.
Related
I'm looking to make a sprite animation editor. I have the loading of my custom animation file done but now need to get the actual ui started. I'm really just stuck on what widgets I would use to actually play my animation. I need to be able to go to certain frame, play, pause, loop, etc. Once I'm done with the viewing portion I plan on adding in the editing.
I've seen AnimatedSprite in qt docs but that seems to only allow playback of sprites in the same file. In my situation sprites can be from multiple image files and sometimes doesn't follow a grid like sprite cutter.
First of all, you should decide whether you want to use QML or Widgets. AnimatedSprite is QML related class. All widget-related classes starts with "Q" letter.
If you decide to use Qt Widgets, I would recommend to take a look at Qt Animation Framework in combination with Qt Graphics View Framework. Most likely it will not let you do everything you want out of box, but it should provide you with a rich set of useful tools.
If you need here are some examples.
Hope it helps.
Have a look at QMovie. This class may provide all the methods you need, as long as you only want to use it for viewing. The QMovie can be passed to a QLabel to show the animation.
QMovie however supports only gif out of the box (and there is a third party plugin for apng files). You would probably have to create your own image handle plugin to support your format.
If thats not applicable or to complicated, you will most likely have to create your own custom widget. Have a look at the painter example. Playing an animation is not that hard if you have all the frames. A simple QTimer to change the image to be drawn in a constant rate should work.
I'm developing an application with C++ and GTK3 but I'm stucked. I've created a visual application with glade which has three columns and one of them, the middle one, is a DrawingArea. In that DrawingArea I want to draw some circles at the point I want to after pressing a button and have different mouse events on that circles (like drag and drop, double click, right click...). I've made the first thing (draw a circle after pressing a button) following the official documentation, but the problem is that I don't know how to do the mouse events, but I thought about it and I have some different solutions (I don't know if they are the bests solutions or maybe there are better):
I think the best way is to create a signal to the cairomm context, but I didn't see anything to do that. Maybe the way would be to create a cairo surface or something like that.
Every time I click to create a circle, I would have to create a gtk widget in which I can handle mouse events. The problem here is that the widget needs to have circular shape and need to be drawable. Is it possible to create a circular DrawingArea? It could be the best. I saw the way to create custom widgets here.
Use goocanvasmm. The problem here is that goocanvasmm has a little documentation (I'm sorry I can not post more than two links because of my reputation) and I think this is not the best solution, I prefer to use cairomm.
This application was written in C using GTK2, and the circles were drawn using gnomecanvas, adding signals in an easy way to each circle; and now I'm moving this application to C++ and GTK3 to renew it.
I'm very new to GTK (and graphical interfaces in general), but I looked for solutions for hours and I don't know what is the best way in order to continue my work.
Thank you for your help :)
It's best to use a canvas library for this such as GooCanvas. Doing it with cairo alone would require you to listen to mouse events on the whole drawing area, and keep track of where the circles were in order to decide which circle the mouse event belongs to - exactly the problem which the canvas library has already solved for you.
If you are having trouble with goocanvasmm documentation, a look at the documentation for GooCanvas' C API combined with knowledge of how the C API translates into C++ will usually suffice. Although the GooCanvasmm documentation seems fairly extensive to me.
I guess this question has been ask before, but I have not found sufficient answer to even start poking around. Most answer refers to catching WM_PAINT method directly and do custom rendering, or use a onwer draw object. However, I did not see a centralized place that has the info. to start researching. Hence, the question.
My goal is to create a very simple GUI program with custom look into it. I prefer the way winamp does their custom look that is customizable through "skins". However, I am not interested in using some cross-platform library like GTK+, QT or wxWidget.
I have some experience in system programming, but not much for GUI. I spent most of my time developing console applications, and I just started doing some QT development. If you can point me in the right direction, I'd be very appreciated.
PS: I am interested in both windows and linux environment.
Everybody,
Sorry for the late reply. I had a chance to have a quick talk with the original developer for winamp, and this is the quick answers I have:
Using skins: Artists create skins, developer will render the skins
To the OS (Windows), winamp is just one pretty box, nothing else. There is a container windows, and that's about it
All controls (button, label, list, etc) are implemented by winamp team themselves. All messages and stuffs are passed as relative position to the container window. WinAmp and the GUI engine has to decide if a button is clicked or if the label next to it is the target, etc.
Rendering artists skins created in XML
I do not have the details on if they use any libraries to do all that, but I am suspecting they do hook a window call directly, and do custom rendering themselves.
GUI skin usually using plug-in mechanism
I guess this is exactly what you are looking for:
https://www.linux.com/learn/tutorials/428800:weekend-project-creating-qt-interfaces-with-gimp?utm_medium=twitter&utm_source=twitterfeed
I also interested in creating custom look of window and widgets.
Speaking about widgets it's not hard, just need to create subclass (if you are using C++) or some widget and implement some methods like draw, handle etc. But this solution is good only if you use some high-level library like GTK, QT, etc. If you want to implement all controls by your own, you may get any graphics library, which can create window and do any graphics inside. For example, SDL2 + Cairo. SDL2 for creating window, Cairo for vector rendering controls/widgets. Both of this libraries are for win and linux. Another option is take opengl/vulkan + some lib for rendering window. It could be SDL2, SFML, GLFW.
If you really interested how it works on low level, then search Windows API for Windows and XLib or XCB for Linux/X.Org.
Speaking about window, I still investigate it. However I have one thought: you may create an empty window and then draw whatever you want. Then you need to add handlers for resizing window on the borders. But I am not sure if it's good solution, and if it won't freezes.
Could anyone suggest me a particular way to implement animation in my Dialog-based mfc program? The animation that I am intending to add is like a construction digger machine graphic that would read the values of the machine parameters and change the shape of the graphic accordingly. Most of the information is read from a text file in terms of the parameters, so I just need to be able to get the animation working.
Thanks for your help in advance.
Well, GDI is easy but ugly and quite slow, GDI+ is also easy, but nicer although generally slower. OpenGL or DirectX are much, much faster but quite hard to program. Other libraries, such as cairo, are also available.
I'd suggest to start with the easiest (maybe GDI+) and see if it is fast enough for you.
Do do that, just Invalidate() the control where you are drawing in a timer, (or when you receive new data), and paint the whole graphic in the OnPaint() function. A basic improvement is to Invalidate() only the region where the new data affects the picture.
If then you notice that your code is not fast enough, come back and ask how to improve it. A concrete example will make it easier to get a more useful answer.
there are lot of articles. Most of them based on drawing in device context
http://www.codeproject.com/KB/GDI/flickerfree.aspx
http://www.codeguru.com/cpp/g-m/bitmap/article.php/c4879
http://www.codersource.net/mfc/mfc-gdi-plus/animation-control-mfc.aspx
I have an application that I want add some cool animations to show state changes. However, wxwidgets would be difficult because I'd have to program these animations in straight gdi. What's the best way to add these effect windows? Should I open a flash window and run a flash sequence or is maybe some other technology? Does .net have something I could code into a dll and run from my wxwidgets binary? I need something that is super easy to draw and set up the animation.
It's hard to say what the best approach would be to achieve "cool effects", but in most cases you would want a double-buffered drawing surface. That's what I've used in similar-sounding situations.
In wxWidgets, you would want wxBufferedDC.
You could prepare animation as a bunch of images (wxImage loaded from PNG, GIF, JPG or whatever files), and then use a timer and paint them on a control. Maybe it sounds like too much, you I believe you could do it in 50-70 lines of code.
Perhaps you just could make a single widget that has a custom paint-event that hand-draws the various widgets inside it? Then you could draw them at the appropriate locations/sizes without having to involve wxwidgets at all, it would just be a bunch of line-draw/rectangle-draw/text-draw commands to update the display for each frame of animation.