First things first: if you haven't yet read 2D, Acceleration, And Windows: Aren't All Graphics Cards Equal?, please feel free to check that one out first, since it's the Part 1 to this Part 2 exploration into the history of 2D in Windows and current issues seen on high-end discrete graphics cards.
In this second part, we focus on the relevance of GDI, explain 2D graphics output more completely, and present to you our 2D benchmark (for the folks who haven't already discovered it on Tom's Hardware DE). In order to fully understand the results from that benchmark, we must first dig into some related theoretical fundamentals.
Direct2D or GDI? Or perhaps both?
Why Do We Still Test GDI in the Era of Windows 7 and Direct2D?
In the first part of this series, a number of readers speculated that, with the introduction of DirectX 10-capable graphics cards and Windows Vista, older GDI methods for 2D graphics output were rendered obsolete. The WPF (Windows Presentation Foundation), along with Direct2D, have been available to Microsoft developers for some time now. Nevertheless, there are plenty of good reasons why GDI (the Graphics Device Interface) remains unarguably meaningful and relevant, which means we must examine its behavior and performance, even for the brave new world of Windows 7. These reasons include:
- The GDI continues to support older graphics cards, while Direct2D requires cards that can support DirectX 10 or better.
- GDI is supported in every known version of Windows, whereas Direct2D is available only in Windows Vista and Windows 7.
- Every graphics application that runs under Windows XP (and older Windows versions) uses GDI
Lots of software developers resist converting their software from older to newer APIs. Even today, many developers continue to turn to the same well-understood programming libraries, even if newer technologies are available. Converting from one library to another also means rewriting and retesting all affected code modules. Because performance improvements that result from converting from an older library to a newer one may be barely perceptible, software developers also balk at making such changes on purely economic grounds (too much time and effort for too small of a result). If you take the implementation of Direct2D in various components of Mozilla Firefox as an illustrative example, you get a sense of the industry’s leisurely pace in carrying out this conversion process. In addition, it would be a form of business suicide for many of these firms to lock the entire community of XP users out of their latest releases. All of this adds up to a single compelling observation: the GDI is likely to stick around until Windows XP no longer represents any significant component of the end-user community.
Then there are technical reasons to explain the persistence of GDI. Key GDI code modules (those that are included and invoked most often in Windows applications) aren't completely portable. Direct2D also consumes significant processing power and system resources, but can do nothing that Direct3D cannot also deliver. And those who elect to skip using Direct3D have usually considered this decision quite carefully. In addition, the GDI works independently of the output devices, such as monitors or printers, that may be in use. Thus, the same routine in a program can render graphics on a monitor, and output to a printer, thereby reducing the code (and its subsequent maintenance and error risk) by as much as one-half. Many of the most affordable printers are GDI devices nowadays, and this situation is unlikely to change any time soon, even in Windows 7, where plenty of drivers for GDI-only printers remain widely available.
Direct2D as a part of Direct3D-Output (D3D)
The Whole Is More Than the Sum of All Parts
We ourselves view the conversion to WPF and Direct2D as a move that’s being pushed forcibly by Microsoft, and as an irreversible technical step forward. But those who get all hot and bothered by new technology should think back to previous introductions, which we'll recap in this piece. Windows XP included, there is more than enough legacy technology hanging around that you can really only face the future if you’re willing to ignore the past. But alas, this disregards the realities in which most users operate, such as the well-known phobia for Windows XP shown by 780G and 785G on-board graphics chips.
We want to revisit our benchmarks from Part 1 here, but this time we’ll use our own custom-built software (readers can also download this tool from our site, and run it on their own PCs). We'll observe that even the most expensive graphics cards fall flat on some of these tests, if they’re affected by drivers that haven't been optimized for what many folks consider an older technology.
- Introduction: Why GDI Output For 2D Graphics Remains Relevant
- The 2D GDI For Windows XP Through Windows 7, In Detail
- 2D Graphics Output Using GDI: Direct Or Buffered?
- The Radeon HD 5000's Symptoms And Their Relevance To Windows 7
- Tom2D: Our Simple 2D GDI Benchmark
- Tom2D: Text Output
- Tom2D: Line Output
- Tom2D Splines/Bézier Curves
- Tom2D: Polygons
- Tom2D: Rectangles
- Tom2D: Ellipses
- Tom2D: Blitting
- Tom2D: Stretching
- Conclusion
- UPDATE: ATI Steps Up With A Hotfixed Driver
BENCHMARK: DIRECT DRAWING TO VISIBLE DEVICE
Text: 8556 chars/sec
Line: 47513 lines/sec
Polygon: 7757 polygons/sec
Rectangle: 6564 rects/sec
Arc/Ellipse: 3874 ellipses/sec
Blitting: 13974 operations/sec
Stretching: 266 operations/sec
Splines/Bézier: 10510 splines/sec
Score: 984
Oh great, more news on a 5xxx series not being able to handle simple apps like CS4.... I have yet to use CS4 on my desktop with my 5850..... I hope Ati comes out with more patches if this is a problem.
BENCHMARK: DIRECT DRAWING TO VISIBLE DEVICE
Text: 8106 chars/sec
Line: 6528 lines/sec
Polygon: 249 polygons/sec
Rectangle: 1484 rects/sec
Arc/Ellipse: 6127 ellipses/sec
Blitting: 379 operations/sec
Stretching: 80 operations/sec
Splines/Bézier: 5263 splines/sec
Score: 362
BENCHMARK: DIB-BUFFER AND BLIT
Text: 12633 chars/sec
Line: 21067 lines/sec
Polygon: 4087 polygons/sec
Rectangle: 535 rects/sec
Arc/Ellipse: 5604 ellipses/sec
Blitting: 1443 operations/sec
Stretching: 213 operations/sec
Splines/Bézier: 12213 splines/sec
Score: 607
Text: 54466 chars/sec
Line: 73135 lines/sec
Polygon: 23943 polygons/sec
Rectangle: 3927 rects/sec
Arc/Ellipse: 26911 ellipses/sec
Blitting: 9827 operations/sec
Stretching: 464 operations/sec
Splines/Bézier: 41911 splines/sec
Score: 2600
Text: 45746
line: 40508
Splines/beziers: 20466
Poygon: 322
Rectangle: 1954
Arc/E.: 3494
Biting: 2406
Stretching: 211
Score: 1150
First, try adding a DDB (device dependent bitmap) test mode as well - even if your DIBs are using the same colordepth as the display mode, perhaps some drivers fail to optimize for this?
Second, what about the power savings mode modern GPUs tend to run in, in 2D mode? I'm not sure what it takes to kick out of the power-savings mode, but perhaps it could be as simple as creating a D3D context and displaying a single frame?
Text: 45496 chars/sec
Line: 44352 lines/sec
Polygon: 12293 polygons/sec
Rectangle: 7013 rects/sec
Arc/Ellipse: 9854 ellipses/sec
Blitting: 7265 operations/sec
Stretching: 642 operations/sec
Splines/Bézier: 36955 splines/sec
Score: 1853
4870 Windows 7 running Cat 9.12
Text: 57405 chars/sec
Line: 42421 lines/sec
Polygon: 14198 polygons/sec
Rectangle: 10724 rects/sec
Arc/Ellipse: 18070 ellipses/sec
Blitting: 16297 operations/sec
Stretching: 615 operations/sec
Splines/Bézier: 37779 splines/sec
Score: 2382
BENCHMARK: DIB-BUFFER AND BLIT
Text: 38521 chars/sec
Line: 145631 lines/sec
Polygon: 22599 polygons/sec
Rectangle: 2572 rects/sec
Arc/Ellipse: 30395 ellipses/sec
Blitting: 10595 operations/sec
Stretching: 1082 operations/sec
Splines/Bézier: 47304 splines/sec
Score: 2904
Windows 7 core i7 920@3.8 ati 4890 Catalyst 10.1
Points, lines, bezier curves, arcs (and circles, a subset of arc), ellipses, unfilled polys/rectangles ... all those aren't easily/efficiently implemented with the core 3D primitive: filled polygons. Perhaps some of it can be efficiently implemented with shaders, but that's uncharted territory for me
Text: 25419 chars/sec
Line: 26376 lines/sec
Polygon: 8153 polygons/sec
Rectangle: 1152 rects/sec
Arc/Ellipse: 8672 ellipses/sec
Blitting: 3359 operations/sec
Stretching: 455 operations/sec
Splines/Bézier: 15977 splines/sec
Score: 1011
CPU: C2D e4300
GFX: GMA 3100
MB: G31
OS: Win 7
Text: 17806 chars/sec
Line: 20636 lines/sec
Polygon: 17975 polygons/sec
Rectangle: 3312 rects/sec
Arc/Ellipse: 23234 ellipses/sec
Blitting: 6199 operations/sec
Stretching: 321 operations/sec
Splines/Bézier: 20157 splines/sec
Score: 1433
BENCHMARK: DIRECT DRAWING TO VISIBLE DEVICE (AMD FUSION: Productibity)
Text: 6140 chars/sec
Line: 5109 lines/sec
Polygon: 5233 polygons/sec
Rectangle: 1017 rects/sec
Arc/Ellipse: 6819 ellipses/sec
Blitting: 1851 operations/sec
Stretching: 104 operations/sec
Splines/Bézier: 5673 splines/sec
Score: 427
BENCHMARK: DIRECT DRAWING TO VISIBLE DEVICE
Text: 43898 chars/sec
Line: 73421 lines/sec
Polygon: 17483 polygons/sec
Rectangle: 2989 rects/sec
Arc/Ellipse: 21805 ellipses/sec
Blitting: 6082 operations/sec
Stretching: 363 operations/sec
Splines/Bézier: 35804 splines/sec
Score: 2138
Windows vista 64, Phenom2 x3 720 (4 core enabled), Catalyst 10.1, ati 5850