FX Composer FAQ


This page answers some of the frequently asked questions about FX Composer.

What is FX Composer?

FX Composer is a fully functional shader development environment for DirectX 9.0 HLSL FX files.  You can always find the latest version of FX Composer and supporting utilities at

How do I use my own models in FX Composer?

FX Composer currently supports the Microsoft .X file format, as well as the NVIDIA .NVB format.  Future versions of FX Composer will include an SDK that supports creating your own importer plug-ins for additional file formats.

Why can't I import .X files?

If refrast is disabled on your system, you will see "Failed to create temporary D3D9 Device!" in the Tasks panel and the import will fail.  Turning refrast on should fix the problem:

  1. Open the DirectX control panel (Start->Control Panels->DirectX)
  2. Click on the Direct3D tab and make sure "Enumerate Reference Rasterizer" is enabled
  3. Start FX Composer and import some .X files

Why does this happen? The .X file importer plug-in creates a temporary device using the reference rasterizer (refrast).  If refrast is not enabled on your system, the temporary device cannot be created and import fails.

This bug will be fixed in the upcoming FX Composer 1.5 release.

Problems rotating objects in the Scene panel?

When you import a .x file that has no animation, you may be unable to rotate the geometry in the scene panel. To work around this problem, use the program that created your .x file, add an empty animation to the model, and then re-import into FX Composer. This problem does not affect .obj files and should be noted when implementing custom importers for proprietary file formats.

Does FX Composer work on GPUs from other vendors?

The shader development features of FX Composer work on any GPU.  Performance analysis features are available for the entire family of GeForce FX GPUs, and future versions of FX Composer will provide a plug-in API for performance analysis on additional GPUs.

How is FX Composer different from other shader tools?

With FX Composer you work directly with .FX files and have access to detailed performance analysis & optimization features that help you create compelling, high performance content for real-time applications.  FX Composer also provides a set of "scene commands" that allow you to simulate running your shader in your own render loop, apply full screen post processing effects and much more.  See the complete list of features on the FX Composer homepage at

Does FX Composer work with Cg or GLSL?

We are always evaluating opportunites to provide powerful tools for developers, but have no plans to add support for other languages to FX Composer.  FX Composer was built to support the large number of developers using HLSL in their applications.

Will FX Composer work on Mac OS X or Linux?

FX Composer was written from the ground up to be a Windows application.  Please let us know if you need a tool like FX Composer on a different platform. 

How much does FX Composer cost?

NVIDIA does not charge for FX Composer.  It is provided for free as part of our developer tools program.  Please let us know if you would like help incorporating similar features in your commercial products.

Other Questions?

More information about FX Composer is available online at