I'm writing a program in C#/Mono to be run on an ARM computer. It needs to be able to get the state of an Xbox controller plugged in to the system. I have tried a number of various libraries (XInputDotNet, for one), but they have all had various issues (like trying to use incompatible native C++ DLLs).
How can I read the state of an Xbox controller on an ARM machine?
P.S. Although there are similar questions, this is not a duplicate. All the solutions for previous questions fail for one reason or another on ARM.
To speak more directly to your task - you need to interface with a USB device. Typically this means opening up a handle to the USB driver, giving you a pipe through which you can read and write data to the USB device. libusb is a great way to do that in Linux userspace applications.
Given that you're going to be doing this in C# on mono, you're going to need to do pinvokes to libusb. If you're not familiar with pinvokes yet, I'd recommend practicing on something small, since they can get complicated very fast; particularly, read about SafeHandles.
There is at least one existing project you could use to base your work off of - xboxdrv, which is a userland C++ application, built on top of libusb, that reads and writes the controller's data and presents it as a standard joystick so that any joystick-aware program can utilize it.
The libusb library, which can be compiled on any Linux platform, including ARM, actually has a sample program (xusb) that can report the status of an XBox Controller.
See https://github.com/libusb/libusb/blob/master/examples/xusb.c#L945.
Related
I am making a C# app to capture graphic from an avermedia pcie capture card.
But it seems that there are no out of box tools to do so.
So I made a C++ directshow app to do the capture, which is a console app and opens a capture window when running.
How can I redirect the output to a C# app? for example, to a CaptureElement?
So you want to have XAML CaptureElement connected to AverMedia PCIe capture card. This sounds like a well-understood challenge overall, however every other piece of technology you mentioned is eventually a bad choice: DirectShow, multiple apps with piping, redirection and fitting of cutsom code to XAML CaptureElement control.
Microsoft has intentionally been limited ways you can integrate different APIs and so there are not so many ways to get everything together.
Let us go over the supposed integration path. The capture card is supposed to be shipped with a compatible driver:
Video capture devices are supported through the UVC class driver and must be compatible with UVC 1.1
When this is the case, such devices are visible to Media Foundation API handling video capture among tasks. XAML CaptureElement would be able to see a video capture device through this API and this way everything is supposed to work without need to fit anything from your end.
If this is not happening, it suggests you are dealing with an unsupported device coming without suitable or compatible driver.
Previous media API in Windows was DirectShow but its days are gone. It remains perfectly working as a legacy framework, a lot of applications out there are still relying on it. Specifically it will not integrate with new technology like XAML and UWP. More to that, even Media Foundation itself, the current media API, in its public offering is lagging behind when it comes to fitting with most recent technology. Having said that it is a good idea to stay well clear of DirectShow here if this is at all possible.
I see no need for cross-process design with video travelling between process through piping. There is no good reason for such design and even though this can work efficiently (Windows itself proves it can work great in terms of performance by having so called Frame Server service in it), this is not to be built on piping. In your case it is unlikely to be have to be built on multiple processes either. Instead you can develop a native code DLL project that takes care of video acquisition and connects to managed code via suitable glue layer: C++/CLI, COM, C++/WinRT and such.
Then next thing is fitting to XAML CaptureElement. The control is designed to work with Windows.Media.Capture.MediaCapture class that talks to hardware and you don't have suitable hardware as you plan to implement your own acquisition layer. Long story short you are not supposed to forward external data to CaptureElement and you would have hard time doing this. Your best strategy is to upload externally obtained data to Windows.Graphics.Imaging.SoftwareBitmap or alike and take involved performance impact as acceptable. That is, you will be dealing with video frames as images.
An alternative way is to upload acquired video frames into Direct 3D 11 textures and it would open you a more performant way of integration with video related controls, such as Windows.UI.Xaml.Controls.SwapChainPanel however it would also require that you put much more development effort in there.
My C# application uses DirectShow and requires DirectX to run. I would like check that DirectX is enabled at start-up, can anyone advise the correct method to do so?
Thanks
DirectShow is not a part of DirectX. There is only some intersection in video renderer using DirectDraw and Direct3D, and wrappers over audio APIs which are in fact no longer independent but wrappers over other APIs. I would say there is nothing to check for and DirectShow is already an OS core component, but if you have some specific concerns then what are they? Maybe you could attempt to create some DirectX object directly on app startup and see if this attempt is successful.
I think I'm right in saying if the DirectX DLLs aren't installed on the host machine, your application wont even start. Beyond that, you should always be checking that creation of DirectX objects succeeds before attempting to use them.
I need to develop a C# touch-screen desktop application with a "modern good-looking" UI.
How would you approach it? I´ve got in mind using Flash (just for the UI) or WPF... but i´m open to any idea or any third-party C# UI you´d know.
Is Flash easy to integrate with C#?
Thanks for your knowledge!
You should look for a AMF remoting library in C#.
Remoting is when you call a function on your server from flash.
AMF (version 0 or 3) is a binary format used to encode object transfered
between client and server
Weborb and fluorine are solutions for this.
see : .NET and AMF
You will probably be doing well with a third party framework to avoid the overhead of writing user interactions, controls, etc.
A couple of options are
http://xamarin.com/
http://www.resco.net/developer/mobileformstoolkit/
A review of these options is provided here.
I recall combining a flash interface with a C# back-end back in university. There's a method called fscommand() that will take a couple of string parameters (I may be mistaken, read up on it) to pass to and from the interface and the C# "code-behind".Flash is an ok option, but if I were you I'd opt for a WPF interface. I'm a huge fan of the telerik libraries, their WPF one allows you to create the most modern-looking interfaces and dashboards. Not to mention that the skills you will acquire while learning enough about wpf will be hugely beneficial in your career as a developer the way things are going (depending, obviously, on what direction you're heading).
FlashBuilder 4.6 has some nice functionality for quickly building a UI that work on a desktop or mobile device. You could use FluorineFX (free) or webOrb on a webserver to send data back and forth to a database server if that were needed. If you build it with the Flashbuilder 4.6 mobile project template, it would work on a iPad, mac, windows pc, or android device as well. Since a pc touchscreen should use the same type of finger gestures as a mobile app, this might be a nice way to go. (I don't actually have a touchscreen on my pc, but it runs well with a mouse, so I'd assume it worked with gestures too).
Adobe.tv has lots of examples of building a mobile app project (Which also runs on a PC) and there is a Flashbuilder 4.6 free trial.
http://flex.org/
We want to write a client for an online service which should be available on as many platforms as possible. This question is about what programming language and framework we should use to create this client.
These platforms are required: Linux, Mac, Windows, iOS (iPhone, iPod, iPad) and Android. The more the better.
For the mobile platforms there is Titanium Mobile. I haven't tried this thing yet, the website says you can develop for both iOS and Android using web skills such as Javascript. I don't know yet if you can deploy for both platforms using the SAME code. It would be great!
There is also Titanium Desktop but I don't like the idea that the complete source code is shared with the final application. Titanium does this for Mobile too but it isn't that easy to modify an app loaded via App Store.
So, what other way is there to create an application which runs on at least the three major desktop platforms? I thought c# with mono would be the way to go but I just realized that you need to use mono with MonoMac in order to publish it on the Mac App Store and use things like Growl. And since MonoMac is naturally only available for Macs, it's again not possible to deploy the mono app on all platforms without rewriting it for at least the Mac. And it would be nice if the app looks "native" on all platforms. Gtk# just does not look good on a Mac. It's "okay" on Windows and great on Linux.
I know we could use Objective-C for iOS and Mac, Java for Android, C#.net for Windows and C#.mono for Linux but the main point is that we don't want to write the same app in a lot of different languages. That would make development and maintenance really hard.
And we prefer languages with C-style syntax which are much easier to learn for us PHP web developers. Btw: We dislike Air and I'm not sure about Java since I never used it but it also does not look "native" and it feels kinda slow.
Edit:
Just a note: It wouldn't be a problem to create an own form for each platform if at least the remaining code is the same. Is it possible to use MonoMac, Gtk# and Win Forums in the same C# application? And I'd prefer C# over C++ as I have no skills in C++, so I first need to check how hard it is to write with Qt.
Another note: We don't plan to spend much money and because we need to pay Apples Developer Programs we want to use free or cheap technology. Preferable Open Source.
Just use C# for all of the above.
The mono project will cover Mac and Linux, with monodroid your android requirements are covered and monotouch will take care of iPod/iPad/iPhone.
In regards to UI - mono has full support for the System.Windows.Forms namespace, so you don't have to use GTK# if you don't want to.
I don't think I need to mention windows support ;)
If you really want to support all those platforms from a single application, your best bet will be to create a web application. With HTML5, such an application can even be cached on the device and used when no connection is available. Also, that strategy would make it feasible to customize the UI based on the device running the app.
You will not have good luck if you set out to build a single native app that runs on Android and iOS, let alone all the other platforms you mentioned. The reason that they're different platforms rather than the same is that they're, well, different. They have different capabilities, run on different hardware, are built with different languages, employ different application models with different user interfaces, and have audiences with different expectations.
The best solution I've come across over the years is Qt SDK.
Great support for all major platforms, Symbian, OS X, Linux flavors, Windows, Windows CE (mobile), Android and iOS partial support and etc.
Its base is C++ but bindings for almost every language (like C#) is available. Lots of help and support is also covered.
The core Qt libs are very fast and extensive, And the whole KDE desktop (of Linux) is done with it. Famous software like VLC and VirtualBox are done in Qt.
Another relatively new way of doing cross-platform development is to use the open source Eto.Forms, which allows you to have one UI codebase target each platform's native toolkit. It is a UI abstraction layer that can target GTK#, MonoMac/OSX, WinForms, and WPF.
There is also an iOS port in the works.
Java sounds like the best fit. It is cross-platform, easy to understand, has a huge userbase and android is based on it.
Depending if you need an offline interaction mode, it sounds like you should develop a web application. You can develop a mobile version and a desktop version and thus support all the of the above platforms. Look at youtube's application for Iphone, it retains the same functionality as the the iphone app but is purely html. Furthermore, html5 capable browsers could also have the ability to run offline.
Crazy as it sounds, check out Flash/Flex - it is cross platform, code once, run everywhere ,now compiles down to native code on e.g. Android and iOS and the 10.1 player is shipping all over. I had to solve exactly this problem and when Flash Builder Burrito catered for mobile after working with it for a while I have switching from C#/Flash hybrid to Flash only for clients. (Our backend is C#/Node/C++, etc).
Depending on your timelines and needs it is something look into.
Some random links to peruse:
Blog post about performance and video to single app multi device
Developing flash and flex applications
Using ExternalInterface in AS3 is it possible to call OS (C#?) functions within XP?
Example: Set the desktop background to a image supplied by a flash app?
If it is possible would it be different calls when applied to different OS. And what about cross over the Mac?
Any information would be great
Thanks
If you're launching the swf from within a C# app, external interface will do just fine. Nothing will change on the flash side, but you'll need to go through a couple hoops to get it to work in C#. It's not as simple as AMF or External Interface to JS.
All the communications to C# get converted to XML describing the data, and you've gotta write XML to send back to flash. Other than that though, its relativly simple.
Here's some info on how to do it. The AS portion is Flash 8/AS2, but the C# portion should say the same.
When working with Flash from a webpage or as a desktop app, you are limited to a small security sandbox and you will not be able to make any relevant OS call. I thought that switching to AIR would give the developper more flexibility but it doesn't seem correct either. From "The Pros and Cons of Adobe Air":
AIR apps have
file access, clipboard access, support
multiple windows, support drag and
drop, and can trigger notifications
(toast in Windows). If you app needs
to interact with the desktop in other
ways, the chances are that AIR is not
suitable. For example, there is no
access to COM automation, and no way
to execute external applications. The
reason is to maintain cross-platform
compatibility. That's a worthy goal,
but it would be good to have a way out
of the sandbox. Unlike Java or .NET,
you cannot extend AIR with custom
native code libraries. Nor can you
call operating system APIs.
As Alex Jillard commented, if your swf is called inside a C# desktop application, you should be able to access more OS funcionalities although I'm not sure how.
You could use as already mentioned AIR. Another idea would be to use HippoHX (I haven't written this, the similarity with my username is just coincidence). It runs on top of the NekoVM and gives you unrestricted (so no limitations like in AIR ) access to the system.