based generation of web images
It is May 2017. My boss has asked me to produce some code to make some custom web images on our website based on text that the user enters into their browser.
The Server environment is Windows 2012 running IIS, and I am familiar with C#. From what I read I should be able to use GDI+ to create images, draw smooth text into them etc.
However, one of my colleagues suggested GDI+ may not work on Windows Server, and that GDI+ is based on older GDI which is 32-bit and will therefore be scrapped one day soon, and that I should use DirectX instead. I feel that to introduce another layer would make matters more complex to write & support.
There are a lot of web pages discussing these subjects as well as performance of each but it feels inconclusive so I ask for experience from the SO community.
So, question: Will GDI work on Windows Server ?
EDIT: Thanks for the responses. I see from them that I was a tad vague on a couple of points. Specifically, we are intending the rendering to image process to be a queue-based process with a service running the GDI+ graphics code. I have just read this from 2013 which suggests that GDI+ should not be run within a service, and suggesting that Direct2D is the MS preferred way-to-go.
EDIT 2: Further research has found this page. It says the options are GDI, GDI+ or Direct2D. I copy the key paras here, though the entire page is a quick read so view at source for context if you can.
Options for Available APIs
There are three options for server-side rendering: GDI, GDI+ and Direct2D. Like GDI and GDI+, Direct2D is a native 2D rendering API that gives applications more control over the use of graphics devices. In addition, Direct2D uniquely supports a single-threaded and a multithreaded factory. The following sections compare each API in terms of drawing qualities and multithreaded server-side rendering.
GDI
Unlike Direct2D and GDI+, GDI does not support high-quality drawing features. For instance, GDI does not support antialiasing for creating smooth lines and has only limited support for transparency. Based on the graphics performance test results on Windows 7 and Windows Server 2008 R2, Direct2D scales more efficiently than GDI, despite the redesign of locks in GDI. For more information about these test results, see Engineering Windows 7 Graphics Performance. In addition, applications using GDI are limited to 10240 GDI handles per process and 65536 GDI handles per session. The reason is that internally Windows uses a 16-bit WORD to store the index of handles for each session.
GDI+*
While GDI+ supports antialiasing and alpha blending for high-quality drawing, the main problem with GDI+ for server-scenarios is that it does not support running in Session 0. Since Session 0 only supports non-interactive functionality, functions that directly or indirectly interact with display devices will therefore receive errors. Specific examples of functions include not only those dealing with display devices, but also those indirectly dealing with device drivers. Similar to GDI, GDI+ is limited by its locking mechanism. The locking mechanisms in GDI+ are the same in Windows 7 and Windows Server 2008 R2 as in previous versions.
Direct2D
Direct2D is a hardware-accelerated, immediate-mode, 2-D graphics API that provides high performance and high-quality rendering. It offers a single-threaded and a multithreaded factory and the linear scaling of course-grained software rendering. To do this, Direct2D defines a root factory interface. As a rule, an object created on a factory can only be used with other objects created from the same factory. The caller can request either a single-threaded or a multithreaded factory when it is created. If a single-threaded factory is requested, then no locking of threads is performed. If the caller requests a multithreaded factory, then, a factory-wide thread lock is acquired whenever a call is made into Direct2D. In addition, the locking of threads in Direct2D is more granular than in GDI and GDI+, so that the increase of the number of threads has minimal impact on the performance.
After some discussion of threading and some sample code, it concludes...
Conclusion
As seen from the above, using Direct2D for server-side rendering is simple and straightforward. In addition, it provides high quality and highly parallelizable rendering that can run in low-privilege environments of the server.
Whilst I interpret the slant of the piece as being pro-Direct2D, the points on locking and session-0 for GDI+ are concerning. Arguably, since we propose a queue-based process, the locking issue is less severe, but if there are immediate and practical restrictions to what a service can do with GDI+ then it looks like Direct2D is the only viable route for my project.
Did I interpret this correctly or has the SO community more recent & relevant experience?
EDIT: With the initial batch of responses slowing up and no sign of a definitive answer, I add this edit. The team here has selected sharpdx as a wrapping library to MS DirectWrite which is itself part of the Direct3D family of API's. We are not 100% certain that sharpdx will be required and we will be comparing it to a solely DirectWrite implementation as we go along looking out for the benefit or hindrance the extra layer represents. We believe at this point in time that this follows the direction MS were trying to suggest in the article sampled above, and that we will be free of GDI/+ shortcomings in a service environment and able to benefit from performance and feature gains in DirectWrite. We shall see.
EDIT: Having delved into SharpDx we are making progress and something mentioned by Mgetz about 'WARP' now makes sense. Direct3D is the underpinning tech we access via the SharpDX API. AS with all low-level graphics work, we request a device context (aka dc), then a drawing surface, then we draw. The device context part is where WARP comes in. A dc is usually fronting a hardware device - but in my project I am targeting a service on a server where it is unlikely that there will be a graphics processor, and maybe not even a video card. If it is a virtual server then the video processor may be shared etc. So I don't want to be tied to a 'physical' hardware device. Enter WARP (good time to view the link for full context), which is an entirely software realisation of a dc - no hardware dependency. Sweet. Here is an extract from the linked page:
Enabling Rendering When Direct3D 10 Hardware is Not Available
WARP allows fast rendering in a variety of situations where hardware implementations are unavailable, including:
When the user does not have any Direct3D-capable hardware When an application runs as a service or in a server environment
When a video card is not installed
When a video driver is not available, or is not working correctly
When a video card is out of memory, hangs, or would take too many system resources to initialize
就你而言，我可能会尝试与SkiaSharp（https://github.com/mono/SkiaSharp）一起从平台/ API细节中抽象出一点
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