From the Readme:
Glass Refraction Demo for Irrlicht 3D Engine
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sio2 'at' users.sourceforge.net
This is a demo of realtime dynamic glass refraction.
The scene - minus any refraction geometry - is rendered into an Irrlicht-managed rendertarget. When rendering the refraction geometry an HLSL shader takes the rendertarget, refraction texture, diffuse texture and calculates the per-pixel refraction.
Usage
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WASD keys or arrow (cursor) keys to move camera.
Alt-F4 or Escape key to exit.
Space - Move refracting window to just infront of the camera's current position.
Requirements
============
Drivers:
Latest DirectX 9.0b drivers [www.microsoft.com/directx],
Latest DirectX9 drivers for your graphics hardware [from your HW vendor].
Graphics hardware with:
Vertex Shader 2.0 support, or better
Pixel Shader 2.0 support, or better.
Notes
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1. This demo may require the Visual Studio 2005 Redistributable Files installed on your machine. These can be obtained from http://www.sio2.g0dsoft.com in the "Misc" section in "Downloads".
2. The background scene is the PerPixelLighting sample from the Irrlicht SDK. Since the refraction shader requires PS2.0, the PerPixelLighting scene is fixed to use the best normal mapping (parallax normal mapping).
3. This Irrlicht build is based on Irrlicht Subversion revision 467.
Credits
=======
1. The base scene for this demo is the PerPixelLighting sample from the Irrlicht SDK.
2. The stained-glass window texture and bumpmap are from the ATI Treasure Chest demo.
3. The HLSL refraction shader was written by myself (SiO2).
