DolphinVS Sample

Microsoft DirectX 8.1 (C++)

DolphinVS Sample

Description

The DolphinVS sample shows an underwater scene of a dolphin swimming, with caustic effects on the dolphin and sea floor. The dolphin is animated using a technique called tweening. The underwater effect simply uses fog, and the water caustics use an animated set of textures. These effects are achieved using vertex shaders.

Path

Source: (SDK root)\Samples\Multimedia\Direct3D\DolphinVS

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

Several things are happening in this sample.

Two vertex shaders are used: one for the dolphin and one for the sea floor. The vertex shaders are assembly instructions which are assembled from two files, DolphinTween.vsh and SeaFloor.vsh.
The dolphin is tweened—a form of morphing—by passing three versions of the dolphin down in multiple vertex streams. The vertex shader takes the weighted positions of each mesh and produces an output position. The vertex is then lit, texture coordinates are computed, and fog is added.
The sea floor is handled similarly, just with no need for tweening. The caustic effects are added in a separate alpha-blended pass, using an animated set of 32 textures. The texture coordinates for the caustics are generated in the vertex shaders, stored as TEXCOORDINDEX stage 1.

This sample uses common Microsoft® 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.