Microsoft DirectX 8.1 (C++)

BumpLens Sample

Description

The BumpLens sample demonstrates a lens 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.

Path

Source: (SDK root)\Samples\Multimedia\Direct3D\BumpMapping\BumpLens

Executable: (SDK root)\Samples\Multimedia\Direct3D\Bin

User's Guide

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.

Programming Notes

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 a lens 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 the following directory: (SDK root)\Samples\Multimedia\Common