| Microsoft DirectX 8.1 (C++) |
The BumpUnderwater sample demonstrates an underwater effect that can be achieved using bump mapping. Bump mapping is a multitexture-blending technique that renders the appearance of rough, bumpy surfaces, but can also be used for other effects as shown here.
Not all cards support all features for bump mapping techniques. Some hardware has no, or limited, bump mapping support. For more information on bump mapping, see Bump Mapping.
Source: (SDK root)\Samples\Multimedia\Direct3D\BumpMapping\BumpUnderWater
Executable: (SDK root)\Samples\Multimedia\Direct3D\Bin
The following table lists the keys that are implemented. You can use menu commands for the same controls.
| Key | Action |
|---|---|
| ENTER | Starts and stops the scene. |
| SPACEBAR | Advances the scene by a small increment. |
| F2 | Prompts the user to select a new rendering device or display mode. |
| ALT+ENTER | Toggles between full-screen and windowed modes. |
| ESC | Exits the application. |
A bump map is a texture that stores the perturbation data. Bump mapping requires two textures. One is an environment map, which contains the lights that you see in the scene. The other is the actual bump mapping, which contain values—stored as du and dv—used to bump the environment map's texture coordinates. Some bump maps also contain luminance values to control the shininess of a particular texel.
This sample uses bump mapping in a nontraditional fashion. Because bump mapping only perturbs an environment map, it can be used for other effects. In this case, it is used to perturb a background image, which can be rendered on the fly, to make an underwater effect.
This sample uses common DirectX code that consists programming elements such as helper functions. This code is shared with other samples in the DirectX SDK. You can find the common headers and source code in (SDK root)\Samples\Multimedia\Common.