I have just installed a program on my pc and after that, an animated arrow is appeared on the screen showing me a new element on the bar:
How can I create this animated arrow ? What API do I have to use ?
It can be made with a window that has a custom shape. One of my colleagues documented how to do this in .NET here:
http://www.atalasoft.com/cs/blogs/jake/archive/2008/05/09/beauty-is-only-skin-deep-skinning-your-winforms-application.aspx
http://www.atalasoft.com/cs/blogs/jake/archive/2008/05/19/beauty-is-only-skin-deep-part-deux-if-it-looks-like-a-duck-it-might-be-a-winform.aspx
The same thing can be done in C++ by following the technique
I'm not aware that such a capability is exposed in an API. I expect the app draws it directly which it is of course perfectly entitled to do.
Related
I'm trying to write a simple AR app in ReactNative, it should simply see 4 predefined markers and draw a rectangle as a boundary on the live preview of the camera, the thing is I'm trying to do the processing in C++ using opencv so as to have the logic of the app in one place accessible to both Android & IOS.
here's what I've been thinking
write the OS dependent code to open the camera and get permissions in (java/ObjC) & the C++ part to do processing on each frame.
call the C++ code (from within the native code) on each frame, and that should return lets say coordinates for the markers.
draw the rect if 4 markers found on the preview in native code (No idea how to achieve this so far but I think it will be native code).
expose that preview (the live preview with the drawn view) to ReactNative (Not sure about that or how to achieve it)
I've looked at the react native camera component but it doesn't provide access to frames & if that's even possible, I'm not sure if it would be a good idea to send frames over the bridge between JS & java/ObjC.
the problem is that I'm not sure of the performance or if that is even possible.
if you know of any ReactNative library that would be great.
Your steps seem sound. After processing the frame in C++, you will need to set the application properties RCTRootView.appProperties in iOS, and emit an event using RCTDeviceEventEmitter on Android. So, you will need an Objective-C wrapper for your C++ code on iOS and a Java wrapper on Android. In either case, you should be able to use the same React Native code for actually drawing the rectangle on top of the camera preview. You're right that the React Native camera component does not have an API for getting individual frames from the camera, so you'll need to write that code natively for each platform.
Programming the GDK a few weeks now, the CardScrollView is a pretty nice interface for displaying cards. However one issue with the UI is showing the user how far along they are in the card stack. In the Mirror API, this is nicely handled by the Slider view at the bottom of the screen as described on the Glass Design page:
https://developers.google.com/glass/design/style/metrics-grids
Unfortunately, I have not been able to get this Slider object to display on the CardScrollView and instead have resorted to a klugey 1 of n text.
Is there any way to get this Slider view to display in the GDK?
This is not yet supported by our API but is currently tracked with Issue #256.
For future reference, this feature has been already implemented as described in the original issue.
You can use the method setHorizontalScrollBarEnabled to show the bar, e.g.
mCardScrollView.setHorizontalScrollBarEnabled(true);
Simple example - on one side we see camera rendered via standard software rendered "Input" on other hand (labeled "Output") rendered via some directX stuff (at least it seems to me) :
So what function is provided by windows api or DirectX api for capturing such mixed scenes?
TightVNC Server can do it, you may want to look into what they are doing. From a simple glance through their source code it looks like they are creating a virtual screen that mirrors the primary screen.
Specifically though, look into the
CreateCompatibleDC and CreateDIBSection API's
As I known, there is not a direct way to capture DirectX render area, although we can see that on the screen. Because the real render action(aka render instruction) happens in hardware layer. So the API in standard SDK cannot know the finally render result, which lead to the black square.
The only way to do this maybe put your hope on the Render layer(such as DirectX engine) itself can support output interface as well as underlying render action. So I suggest to check some documentation to find if there indeed is.
DirectX can present to a limited subsection of the window that you give it, enabling you to create small regions of DX content in larger windows.
I'm trying to figure out how to create a graphical interface, in X11, which exists outside of a window manager's/desktop environment's standard window frame. For example, when Thunderbird finds new mail, it shows a special alert in the lower right hand corner of the screen which is shown without any frame (no close/minimize buttons, etc.).
I'm specifically interested in doing this in QT with C++, but if someone knows a solution with a different graphical library, that would be helpful too.
For QT pass Qt::FramelessWindowHint as a window flag when you construct your top level widget.
See here for more info:
http://doc.qt.nokia.com/main-snapshot/qt.html#WindowType-enum
You can do this with X as well although I haven't done so in a long time.
http://www.xfree86.org/current/XCreateWindow.3.html
With GTK you would use gtk_window_set_decorated(), which would probably be Gtk::Widget->set_decorated() (I think, I don't use gtkmm).
http://developer.gnome.org/gtkmm/unstable/classGtk_1_1Window.html#a67adb1d8051a38e0e5272f141bb8778c
I'm tasked with modifying an existing c++ codebase which uses directdraw for its UI. Is it possible to make use of a browser control that renders onto one of the (existing) directdraw surfaces? If so, can anyone point me in the right direction on how to get started? (or an alternative approach)
Regards all,
Jaime
You should have a look at Awesomium.