With the release last month of HDX 3D for Professional Graphics as a feature of XenDesktop, Citrix now offers two alternatives for delivering high-end 3D graphics from hosted applications. Let's compare these two solutions.

HDX 3D Pro Graphics on XenDesktop

Our premier solution for 3D professional graphics is based on hosted Windows desktops and works with either the XenDesktop 3 or XenDesktop 4 Desktop Delivery Controller. HDX 3D Pro Graphics features our most advanced technologies for data compression, making XenDesktop the best solution on the market for delivering 3D graphics to remote workers. For top level performance, we offer GPU-based compression, leveraging NVIDIA graphics processors with 96 or more CUDA cores. The compression level is automatically adjusted based on bandwidth. Just below that is CPU-based JPEG XR compression (no special GPU required). JPEG XR (the 'XR' stands for 'Extended Range'), formerly known as HD Photo, is an ISO/IEC standard for high dynamic range image encoding. These compression options are supported by the HDX 3D online plug-in for Windows, a special version of the ICA client. With advanced compression and other clever innovations, HDX 3D Pro Graphics delivers a good experience even at 2 Mbps and 200 ms roundtrip latency. And, of course, it delivers a high definition "like local" experience on high bandwidth, low latency connections.

Application compatibility is excellent with HDX 3D Pro Graphics because the applications run on a standard Windows XP operating system (and Windows 7 support is in development). It doesn't matter whether the applications use DirectX/Direct3D or OpenGL or whatever. HDX 3D supports True Color, important when a very large number of colors, shades, and hues need to be displayed, as with high quality photographic images or complex graphics. Customers are already using HDX 3D to work with models with more than a million parts, and 64-bit OS support is coming soon, which will enable huge amounts of memory to be addressed.

These comments from our customers sum it up best:
• So far this is the only product to have anywhere near acceptable performance
• Everyone is loving it
• 50 to 75% better than our existing solution
• In pure Swedish, it is "sh$@#ing good"!
• At 1.5 Mbps it is still very usable
• We have been extremely impressed

HDX 3D on XenApp for Windows Server 2008

For many organizations, HDX 3D on XenApp provides a great solution for delivering professional graphics, since Windows Server 2008 now enables a graphics card to be used for 3D rendering on Terminal Services / Remote Desktop Services. While hardware acceleration is limited to DirectX/Direct3D-based applications, that may be all you need depending on the specific applications your end users require. OpenGL based applications are CPU-rendered but they perform much faster on 64-bit Windows than on 32-bit so you may find that to be adequate. Of course, if you really need hardware acceleration for your OpenGL applications, go with HDX 3D Pro Graphics on XenDesktop.

Compression options with HDX 3D on XenApp are not quite as extensive as on XenDesktop but are generally sufficient for intracontinental WAN access. The highest level of compression is obtained by selecting Heavyweight JPEG, a special variant of JPEG that uses arithmetic encoding instead of the normal Huffman encoding. It gives a further reduction in bandwidth of around 10 to 20% without changing the pixel quality at all (compared to standard JPEG), at the cost of higher CPU consumption. With Progressive Display, users get a responsive experience even over WAN/Internet connections because images are delivered with lossier compression while being moved and quickly resolve to full resolution when motion stops.

A single graphics card in the server can support multiple concurrent users, depending on their usage characteristics. I spoke with a customer using an entry-level NVIDIA FX 370 GPU and they support four concurrent users on an HP 360 G5 server with a dual-core Xeon processor and 4 GB of memory running 32-bit Windows Server. They estimate that they will be able to support 12 to 16 simultaneous users on a dual quad-core server with 64-bit Windows Server and 32 GB of memory. Again, it depends on the application and the work profile of the users. A more powerful GPU, like the NVIDIA FX 5600 or 5800, will help with scalability, too.

HDX 3D on XenApp supports lossless compression (important in Healthcare), but color depth with DirectX hardware acceleration is currently limited to 16-bit High Color. True Color support (16 million colors) is offered with CPU-based rendering, and True Color with GPU hardware acceleration is planned for the near future, making HDX 3D on XenApp a great option for delivering PACS applications over hospital campus networks.

A Look Ahead

How will these technologies evolve in the future? 64-bit Windows XP and Windows 7 support is planned for HDX 3D Pro Graphics on XenDesktop, and True Color support is coming soon for HDX 3D on XenApp. Windows Server 2008 R2 is likely to bring some benefits, too. And as the graphics and hypervisor vendors introduce GPU virtualization, we expect to leverage that on both XenApp and XenDesktop; some exciting progress in this area is already happening in the lab. Expanding the VM Hosted Apps feature of XenApp to encompass 3D graphics apps would be a natural step.

Tell Us about Your Experience with HDX 3D

If you're using either of the HDX 3D technologies described above, I'm sure other customers would like to hear your story. Please tell us about the 3D applications you deliver, your data center and network, and how your users are benefiting.

Derek Thorslund
Citrix Product Strategist, HDX

As announced on August 31st, HDX 3D for Professional Graphics is now available for download. There's also lots of great documentation on HDX 3D Pro Graphics now on our Support site (scroll down to the bottom of the Product Documentation for XenDesktop 3 page). Or if you are just looking for a high-level overview, be sure to visit hdx.citrix.com.

Here are some highlights of this new XenDesktop feature:

• Supports the delivery of 3D professional graphics applications, both OpenGL and DirectX based, which need graphics hardware (GPU) acceleration for optimal performance.
• Works as an add-on to XenDesktop 3 and XenDesktop 3 Feature Pack 1.
• Automatically adjusts compression based on bandwidth and available resources. Delivers full HDX user experience on a LAN (100 Mbps) and very usable, interactive experience over a WAN (2 Mbps or above, with up to about 200 ms roundtrip latency). Makes desktop virtualization viable and practical for design engineers, architects, and other professional graphics users.
• Supports high resolution monitors (e.g. 1920 x 1200). For best results over limited bandwidth WAN connections, resolutions of 1280 x 1024 or below are recommended.
• Provides a real-time image quality configuration tool with an easy way to switch between a sharper image or smoother motion (great when working on  a limited bandwidth connection).
• HDX 3D host workstation (e.g. blade or rack workstation in the data center) is supported on Windows XP SP3 32-bit Professional.
• HDX 3D online plug-in for Windows (client) is supported on Windows XP, Windows Server 2003 and Windows Vista. The plug-in is supported on both 32-bit and 64-bit OS versions.

Download a free Eval and try it out!

Derek Thorslund
HDX Product Strategist

If you have a Direct3D based application that consumes a lot of CPU running on Windows Server 2003, consider hosting it on XenApp 5 for Windows Server 2008. The reason? Under WS08, Direct3D apps can take advantage of graphics processing hardware on the server to do the graphics rendering. As a result, you'll likely find that you can provide better performance to your users and increase the number of concurrent users per server compared to using software rendering (see my earlier blog post). The one key limitation is that the apps must run in 16-bit (5-6-5) color mode ("High color") since the solution does not currently support 24-bit or 32-bit color. Also, running on a hypervisor is not yet possible, until the hypervisor and graphics vendors introduce GPU virtualization technology.

DirectX hardware acceleration can be used together with the Progressive Display feature of HDX 3D. One customer recently commented that the bandwidth requirement to deliver a particular Direct3D graphics application with good performance using these technologies was 1.5 Mbps for the first user plus 0.5 Mbps for each successive user. This has made XenApp a very attractive platform for delivering the application to their remote users.

Derek Thorslund
Product Strategist, HDX Multimedia Virtualization

As I promised in my blog post about SmartRendering (a key aspect of HDX Adaptive Orchestration), here's a video that demonstrates a new Citrix technology for leveraging the graphics processor on the user's PC or deskop appliance to locally render DirectX graphics. HDX Adaptive Orchestration queries the graphics capabilities of the endpoint device and intelligently determines how to combine client-side and server-side rendering. Furthermore, rendering decisions can be made based on available network bandwidth or application characteristics. The result is a high definition user experience, increased server scalability and optimal use of network bandwidth. This video shows how the Windows Aero desktop and WPF-based data visualization applications can be delivered using DirectX command remoting while an OpenGL-based GIS application is delivered using accelerated bitmap remoting.

Derek Thorslund
Product Strategist, Multimedia Virtualization

In this 4-minute video I interview Nitin Desai, team lead for the 3D professional graphics subproject of our Apollo multimedia virtualization initiative, and he demonstrates a high-end CAD application - CATIA V5.19 from Dassault - running on XenDesktop with graphics hardware acceleration. This technology, available as a Tech Preview, enables organizations to deliver DirectX and OpenGL applications and large 3D models over DSL-like network connections while keeping their intellectual property safe within the data center.

Derek Thorslund
Product Strategist, Multimedia Virtualization

It is always exciting when the first emails start to come in with feedback on a new software release. A few weeks ago, the Apollo team put out a second Tech Preview release of our accelerated bitmap remoting technology for 3D graphics acceleration on XenDesktop. This release introduced support for delivering 3D professional graphics applications -- both OpenGL and DirectX based -- over a DSL-like WAN/Internet connection (1.5 - 6 Mbps). With this new technology, companies can keep their intellectual property safe in the delivery center while enabling workers to access 3D applications remotely, even from another continent. Here are some of the early comments:

• "We have been extremely impressed by early results while testing the Apollo Tech Preview with [Autodesk] Revit Architecture." -- Global architectural firm, testing over high latency trans-Atlantic WAN links.
• "The [test subjects'] reactions are positive so far. At 1.5 Mbps it is still very usable." -- Major software vendor.
• "So far this is the only product to have anywhere near acceptable performance." -- Top tier system integrator.
• "[We're] doing user testing and so far everyone is loving it." -- Diversified manufacturer of commercial and defense products.

Based on the positive response, we are now accepting additional organizations into our Tech Preview Program. So if you'd like to "kick the tires", please complete the application form at www.citrix.com/apollo3Dgraphics.

Derek Thorslund
Product Strategist, Multimedia Virtualization

Can you run Direct3D apps on XenApp? What about WPF apps?

Direct3D, part of Microsoft's DirectX API, is used to render 3D graphics in applications where high performance is required. Direct3D apps are not generally supported on XenApp because they require hardware acceleration. That's what kicked off the 3D acceleration technology being developed by Citrix under project Apollo. However, some Direct3D apps will fall back to software rendering, so they can be hosted on XenApp. It depends on whether the software developer has enabled fallback to the software rasterizer. Be aware that Direct3D apps may consume a lot of CPU to do the graphics rendering, especially if they make use of a lot of fancy effects. You'll probably want a multi-core server with lots of memory to deliver these apps.

WPF (Windows Presentation Foundation, the graphical subsystem of .NET Framework 3.0 and above), although Direct3D based, automatically falls back to software rendering when no GPU is available. WPF apps have been supported on XenApp as of PS 4.5 FP1 which was released in September 2007. They will run on XenApp for Windows Server 2003 when 16-bit or "5-6-5" color (also called "High color") is configured. With Windows Server 2008, 24-bit or "8-8-8" color ("True color") is also supported.

Depending on the WPF functionality that is leveraged by the application, performance and scalability on XenApp will vary. SpeedScreen Progressive Display optimizes the delivery of rendered graphics to the client device via compression and auto-sharpening. However, WPF applications using intensive 3D graphics or fading effects will consume more CPU and memory than typical GDI applications, so you can expect server scalability to be lower. Another challenge for project Apollo . . .

Derek Thorslund
Product Strategist, Multimedia Virtualization

Sit back and listen in as I speak with Doug Brown, Citrix Technology Professional and Microsoft MVP, about the Citrix Multimedia Virtualization Initiative and the new technologies being developed by the project Apollo team in this DABCC Radio podcast...

Derek Thorslund
Product Strategist, Multimedia Virtualization

Did you miss the Apollo Accelerated Bitmap Remoting demo at Synergy in Houston? Click here to view a brief video recorded by Vishal Ganeriwala, featuring "yours truly" and Daniel L'Hommedieu from our Engineering team.

Derek Thorslund
Product Strategist, Multimedia Virtualization

The Project Apollo multimedia virtualization team has just released the first Technology Preview of Accelerated Bitmap Remoting, a new technology that leverages graphics processor hardware acceleration to efficiently deliver high end 3D professional graphics and imaging. Although most customers' graphics needs are already well met by SpeedScreen Progressive Display (a revolutionary technology introduced in XenApp Presentation Server 4.5 and also included in XenDesktop), working with large 3D graphics models often demands the added computational power of a graphics processing unit (GPU). Project Apollo follows in the footsteps of Project Pictor which developed the technology behind Citrix's new Virtual Design Studio product for applications built on the popular OpenGL graphics API. Since many software vendors are now introducing applications using DirectX, the Apollo team has been busy researching new techniques for supporting the full range of Windows-compatible 3D graphics technologies. The Apollo technology also delivers Microsoft Windows Vista Aero desktops with full "glass" effects and Flip 3D animation.

This Tech Preview release marks the completion of phase one of project Apollo, focused on verifying the ability of this technology to efficiently capture graphics from a very wide range of professional graphics applications. Optimizations to reduce network bandwidth consumption, including enabling SpeedScreen Progressive Display to work along with Accelerated Bitmap Remoting, are in the works for the next phase of the project.

If you'd like to nominate your organization to evaluate this Tech Preview release, please visit www.citrix.com/apollo and complete the application form. The Apollo web site also provides answers to frequently asked questions and information on technical prerequisites.  

Derek Thorslund
Product Strategist, Multimedia Virtualization

The Apollo team is busy developing several new technologies for multimedia virtualization. Details of the upcoming Tech Preview release of Apollo Accelerated Bitmap Remoting have now been posted on the Citrix.com web site. This technology expands Citrix's capabilities for high-end professional graphics and 3D medical imaging beyond OpenGL. This video demonstrates Accelerated Bitmap Remoting delivering Autodesk Inventor, Autodesk Revit Architecture and Google Earth over ICA, leveraging the graphics processor on a Windows Vista host.

Derek Thorslund
Product Strategist, Multimedia Virtualization

Our project Apollo technology for remoting Vista Aero and any multimedia application that can run on Vista just keeps getting better. This video gives you a sneak peek at the latest version of Apollo, demonstrated by Juan Rivera (Citrix Development Manager) in the Tech Lab at Citrix Summit 2008 in Orlando.