Does someone know a fast way to add the ability to rotate and move a 3D model using Qt?
Obviously, I have to make changes to the world matrix based on the mouse and keyboard movements, and hence I should somehow handle the appropriate mouseEvents and keyboardEvens.
For a 3d camera this seems a bit tricky and although I could implement it myself, I'd better stick to something ready.
Does anyone know or have an example which handles this kind of actions and reflects them to the world matrix?
Thank you.
This might be what you're looking for. It is an example that loads .obj models and allows you to rotate them with the mouse. It also shows you how to render Qt dialogs within the OpenGL scene.
Related
I have seen some similar questions asked but no definitive answer.
I have a background image that I'm using for my main menu for a cocos2d game. I plan to have it animated but not sure what is the most efficient way to do this. One idea was to have multiple images to create the animation but I was thinking this may take up too much memory as each image would be quite big.
The other idea was having one background image as a sprite and then having child sprites of that image that are animated with ccaction. The only thing is I may not be able to create such an elaborate animation if I do this.
I just wanted to get some feedback on this to see what would be the best approach.
Thank you,
Making a frame-by-frame animation of the whole screen would make your app size litteraly explode.
You should definitely go with your 2nd idea, i.e have different sprites for each animated component and use actions to animate them.
Check out CocosBuilder: it provides a nice UI for designing such complex animations
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 am working on a graphics game project in OpenGL and I want to make a front page of the game containing a image, few buttons and some text. Buttons on click perform different actions e.g. start button for starting the game , Can anyone please suggest me , How can I do it?
How can I do it?
Well, by implementing it. OpenGL is not a game engine, nor a scene graph, nor a UI toolkit. It's merely a drawing API providing you the means to draw nice pictures, and that's it. Anything beyond that is the task of either a 3rd party library/toolkit, or your own code, or a combination of both.
A usual approach to model this behaviour is by introducing application states. Here is a related question.
You could model your StartScreenState by drawing a plane with buttons using an orthogonal projection and not drawing (or not having initialized yet) the rest. When the player clicks on 'start', you can switch to perspective projection and display game contents.
I don't know that I would even use OpenGL for that. OpenGL is for rendering colored/textured triangles/quads so that you can do tons of stuff graphically. There's no such thing as "load an image to coordinate x,y on the screen". The equivalent would be "draw two triangles with these vertices that make up a rectangle and are textured with this image". Which is why I would probably stay away from OpenGL to do this, because you don't really need to use any of the awesome features that OpenGL has.
A very common UI framework that I believe nestles in with OpenGL well if you really want to use the two together is Qt. It should make your life easier in terms of UI stuff. See wiki and dev page.
Hey i'm trying to make a GUI lib with SFML, and everything's done except one problem: Making the Interface stay still even when the camera moves or zooms in.
This would be easy to fix if zooming wasn't possible, but zooming out means scaling the contents of the Interface up, which causes it's text/images to become blurry.
Does anyone have a way to get around this issue? (preferably only using SFML, but if i must i can add OpenGL stuff....)
Stop using the same camera and perspective matrices for your GUI as you do for your scene.
In the case of SFML apply a different view, then restore the old one.
I have a problem about a simple mpi program.This program have some 3D points and these points are moving during the program. I created an simple code by implemented c++ and then I tried to add an simple gui. I used gnuplot library and I have a problem. When I call the gui function the gui is created and it is disappeared at the same time. I mean, point object have x,y,z coordinate and I have an array that includes point objects. I want to create them as gui. Can you help me about this problem?
Thanks for any help..
what about Qt? You could use the Qt Graphics View Framework to simulate the 3D-environment - it even supports coordinate transformation (ok, it was originally designed for 2d scope). It supports OpenGL and maybe you are able to simulate the 3D points by drawing dots and setting their positions using simple cosinus and tangens mathematics.
Don't get afraid of the many functions and classes Qt offers - it's very easy and fast to learn - just check out the simple tutorials and after that you right can start your gui!
...and if you are used to Qt, you'll never want to miss it :)
Could it be that the plot is up correctly but that then your program ends? Ie everything's correct, the window goes up, but the next thing that happens is that the program is done, and the window gets destroyed? Try putting in a couple lines that wait for a keypress right after you throw up the window. Then, the window will stay until you press a key (and then the program will end).