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Original article
The Unigine engine is comparable to Epic's Unreal and id Software's Doom architectures. On a regular basis the development studio releases tech demos with benchmark options. The new Unigine demo Heaven (Download) delivers for example DirectX 11 and Tessellation, one of the API's most important features. For DirectX 11 Tessellation polygons are dissected. This process is GPU accelerated and allows developers to use more detailed models. In Direct 3D 11 Microsoft utilizes a tessellator that is supported by two new Shader levels. The Hullshader calculates the level of detail of the tessellation per patch. For this it uses the checkpoints calculated by the Vortexshader. From the tessellation results the Domainshader creates Vertics, which are dealt with by the pipeline as usual. Furthermore the Heaven benchmark makes extensive use of Screen Space Ambient Occlusion (SSAO), volumetric clouds (particle effects) and a fluid day-night-cycle.

You don't have a DirectX 11 graphics card? Don't worry, Unigine also supports DX10, DX9 and OpenGL - without Tessellation features of course.

Unigine Heaven: DX 11 Tessellation in action
The first graphics cards with a DX 11 hardware tessellator are Ati's Radeon HD 5000 models. In order to make use of this feature you need Windows 7 or a patched Vista. If this is the case you can switch Tessellation on or off in the Unigine benchmark. If it is active, diverse objects like walls or bricks are modeled with a multiple amount of their original number of polygons. This way furrows and bumps get "noticeable” physically. The result looks excellent and has an andvantage in contrast to Parallax Occlusion Mapping (POM) and similar techniques: It is affected by Anisotropic Filtering and Multisampling Anti Aliasing.

Click to select Tessellation settings

Tessellation off DX11 Tessellation on

Click to select Tessellation settings

Tessellation off DX11-Tessellation on

Click to select Tessellation settings

Tessellation off DX11 Tessellation on

Unigine Heaven: Graphics cards benchmarks
Although the GPU accelerated tessellation is much faster than the CPU version, but it nevertheless costs a lot of performance. On a Radeon HD 5870 in DX 11 mode the frames per second drop by 39 percent as soon as tessellation is activated. Surprisingly a Radeon HD 5770 deals a little better with the additional work and drops only 31 percent. Current Geforce cards do not support Hardware Tessellation.