Are GDI, GDI+ and OpenGL really obsolete/deprecated? [closed]

Answer 1

Because OpenGL is a standard, it should be considered equally deprecated as C or C++ so it is a matter of time before the entire Windows API -- which today has become a compile once run on every x86 machine API thanks to Wine -- is considered deprecated in favour of .NET and C#.

I use GDI for simple graphics and OpenGL, when I need accelerated 3d.

Another aspect is that Microsoft's build-in implementation of OpenGL is definitely to be considered as deprecated since it is just version 1.1 or something, but that has been for a long time.

Answer 2

If you want to support Windows XP, then you're supporting a "legacy" operating system, and as such, using a "legacy" graphics framework is the logical choice.

Even if that weren't true, let's just say that I disagree with the advice given by the linked MSDN article. The "legacy" status here has more to do with which technology the Windows team thinks is cool this week. The status designation of "obsolete" just means that the group responsible is no longer accepting or fulfilling bug reports (except for critical security issues). Not too big of a deal—these technologies have been around long enough that they're fairly feature-complete and stable.

GDI isn't going anywhere, so if you need something rock-solid that is guaranteed to be supported anywhere and everywhere, that's what I would go with.

If you need a bit more 2D capabilities than GDI offers (e.g., alpha channel transparency), then you could consider using GDI+. It's nearly an order of magnitude slower than GDI, but that's not too big of an issue on modern machines with more power than you could ever want. This, too, is going to be supported for a very long time to come.

That said, if I were writing a new app today, I probably wouldn't bother with OpenGL. There's very little that it offers in benefits over Direct2D and DirectWrite, which are both what Microsoft is pushing as the replacements for GDI/GDI+. There might be some benefit to using OpenGL if you absolutely must target Windows XP because as far as I can tell, Direct2D/DirectWrite are only supported on Vista and later, but that's because (as I mentioned originally), Windows XP falls squarely into the "legacy" or "obsolete" camp itself. Alternatively, if you already know OpenGL well and don't have time or the desire to learn Direct2D/DirectWrite, then it might make sense to continue using it in a new application.

Don't let the verbiage of the MSDN article scare you. Choose whatever technology makes the most sense for your specific use case given all of the available information. By the time any of these technologies go away completely, you'll have to re-write the app completely for a dozen other reasons.

Edit: Hmm, it looks like DirectWrite has also been declared (by some people at least) "obsolete" as well, having been replaced by Direct2D. That's funny, it hasn't even been around long enough for me to bother learning it. I guess that only goes to support my earlier argument that "obsolete" simply designates that a particular technology is not what is currently considered to be in vogue by the Microsoft devs.

I'm personally waiting until all the bugs get worked out of this stuff (and we decide on a semi-permanent standard) before I make the switch for any of my applications. Everything I've seen written in DirectDraw or Direct2D has had serious rendering bugs and is a performance nightmare, even on reasonably competent machines. Sure, they only show up sometimes, under the right conditions, but that's too much for me. And I swear, the blurry text shows up all the time. Not being able to read what's on screen is a deal-killer for me and my users. GDI doesn't have this problem, and it's not going anywhere.

Answer 3

OpenGL isn't deprecated, Microsoft's implementation of it is. Microsoft's implementation is stuck at version 1.1, which is old. The current version of the standard is past version 4. If you want to use OpenGL, it is fully supported by NVidia, ATI, and Intel graphics cards on the Windows desktop, but not in Metro Windows Modern UI apps, is an industry standard, and also works on Mac and Linux. If you need a software fallback implementation, Mesa has got you covered, and it even works on DOS. (Since Mesa can render into memory buffers, there's no reason it won't work in Modern UI apps, but you probably don't want to do this because it can be slow.) One thing of note is that WGL, the API for accessing OpenGL functionality on the Windows desktop, depends on GDI (which is deprecated) so you probably want to use something like FreeGLUT or SDL instead if you want to future-proof your application, which also nets you platform independence.

OpenGL ES is a variant of OpenGL which works on Android and Apple iOS. It is also accessible in JavaScript via WebGL, which Internet Explorer 11 will support (and pretty much every other browser already does.) ANGLE provides a hardware-accelerated implementation of GLES for Windows which piggybacks off of DirectX (version 9 or 11) and thus should work in Modern UI apps as well. Once again, Mesa's got the software implementation covered.

TL;DR: OpenGL is not only not deprecated, it is cross-platform, standard, and has tremendous momentum in the industry. GDI and GDI+, well, not so much.

Answer 4

Are GDI, GDI+ and OpenGL really obsolete/deprecated?

This is not true for OpenGL. OpenGL 4 allows you to use geometry shaders on winxp. Which isn't possible with DirectX (DirectX 10 and up isn't supported on WInXP). It is also one of the only cross-platform 3D APIs out there.

From a business point of view MS is interested in promoting DirectX since it is their technology that lock Developer into windows platform (they're also interested in making DirectX more attractive for developer, but that's another story). So it makes sense that they aren't keen on promoting OpenGL.

What else should be used?

I'd advise to stop using platform-specific tecnologies when possible. Grab cross-platform framework and use it for your application. There's Qt, GTK, wxWidgets and other toolkits for GUI apps, and SDL(and alternatives) for games. This way when platform developer decide to make ridiculous decision (like not supporting DX10 on WinXP) you dislike, you'll be able to move elsewhere with minimum development cost. Qt is also ridiculously powerful and at the moment I have no reason to use something else for GUI development. Still, situation can change in the future.

In short, while developing for certain platform you should keep in mind that platform developer might have their goals that are not compatible with your wishes. Discovering that your source has become locked into single platform isn't very pleasant experience. Your own goals should be the first priority, and if os developer tries to make you use certain technology you don't like, then you shouldn't support that technology.

Answer 5

Yeah, about OpenGL, it actually outperforms DirectX in many ways both resource and display wise. It will never be promoted by Microsoft because it can't own OpenGL, not to mention most people don't do their research and Microsoft can claim it is old. Truth is opengl is opensource standard and evolves at a much faster rate than closed does because it is more than 1 room of developers paid to work on it. Also Microsoft has contracts with many companies to release using only Microsoft's software, this causes more business for Microsoft and less to use the more advanced OpenGL standard. It is a interesting lock up if you will, Microsoft creates these contracts so that many programs are written in DirectX to keep business for Microsoft, and no company will refuse it because Microsoft has about 80%+ home user market.

Answer 6

I suspect that Microsoft's definition of "legacy" has little to do with what any sensible developer should do, and is instead based on some Grand Rewrite of the Windows API.

Starting at around Windows Vista, Microsoft has been redesigning many of their API's. We now have MMDevAPI as the One True Sound API, WIC is the One True Image File API, etc. From what I've seen/heard, these new API's are much better than the old ones, and the "legacy" systems all work based on the new ones. In Windows Vista and later, DirectSound is entirely based on MMDevAPI, and components that need to read image files do it via WIC.

Windows 8 will have an ARM version, which it appears will support only a subset of the current Windows API. We won't know for sure until Windows on ARM is released, but, based on the libraries included for the ARM platform in Visual Studio 11 (ref: http://www.winehq.org/pipermail/wine-devel/2012-March/094559.html), it's looking like GDI+ and OpenGL will not be available. GDI is available for linking, but that doesn't necessarily mean it's intact.

This new API's from Vista and later roughly correspond to the libraries in the VS11 ARM target. I'm guessing that anything on that list is there because it's either the latest and greatest way to do what it does, or it's too technically important to discard (for now). Thus, "legacy" is anything that's not the latest and greatest way to do at least one thing.

I'm not sure what is the One True Graphics API. Already we have Direct2D, Direct3D, DirectComposition (which, by the way, is not available until Windows 8), DirectWrite, and DXGI. DXGI seems the closest, but I don't have a deep enough understanding of the graphics API's to say. I suspect gdi32 is technically very difficult to get rid of. How are non-legacy applications meant to find out when part of a window has been revealed and therefore must be painted, without using WM_PAINT, which involves an HDC, and how could a library do that on an application's behalf without replacing its window procedure? How are we meant to make semi-transparent windows without using UpdateLayeredWindow, which takes an HDC? How much does user32 depend on gdi32, and can they really be separated?

From a technical standpoint, Windows can easily get rid of GDI+ and OpenGL, but I'm not convinced that getting rid of OpenGL will work out, even on a new platform that doesn't promise any backward compatibility. It seems too valuable to developers. GDI+ isn't so important, but it's very easy for a third party to provide a replacement.

I would say use any of the API's you listed, and the worst that's likely to happen is that you have to rewrite your UI if you want to port your app to metro or Windows on ARM. GDI is a fine choice if your needs are simple and you'll be coding directly for the Windows API. There aren't many situations where I'd recommend GDI+ over OpenGL as a drawing API. GDI+ is slow, limited, and only available on Windows. The GDI+ API is simpler because it's 2D, so maybe it's worthwhile if you need to do something very simple but with anti-aliasing.