Microsoft DirectX 9.0

Point Sprites Sample


The Point Sprites sample shows how to use the new Microsoft?Direct3D?point sprites feature. A point sprite is a forward-facing, textured quad that is referenced only by (x,y,z) position coordinates. Point sprites are most often used for particle systems and related effects.

Not all cards support all features for point sprites. For more information about point sprites, refer to the Microsoft DirectX® software development kit (SDK) documentation.


Source: (SDK root)\Samples\C++\Direct3D\PointSprites

Executable: (SDK root)\Samples\C++\Direct3D\Bin

User's Guide

The following table lists the keys that are implemented. You can use menu commands for the same controls.

ENTERStarts and stops the scene.
SPACEBARAdvances the scene by a small increment.
W, SMoves forward and back.
E, QTurns left and right.
A, ZRotates up and down.
ARROW KEYSSlides left, right, up, and down.
F1Shows Help or available commands.
F2Prompts the user to select a new rendering device or display mode.
F3Animates the emitter.
F4Changes color.
ALT+ENTERToggles between full-screen and windowed modes.
ESCExits the application.

Programming Notes

Without Direct3D support, point sprites can be implemented with four vertices that are oriented each frame towards the eyepoint, much like a billboard. With Direct3D, though, you can refer to each point sprite just by its center position and a radius. This saves processor computation time and bandwidth when uploading vertex information to the graphics card.

In this sample, each particle is implemented using multiple alpha-blended point sprites, giving the particle a motion-blur effect.

This sample uses common DirectX code that consists of programming elements such as helper functions. This code is shared with other samples in the DirectX SDK. You can find the sample framework headers and source code in (SDK root)\DXSDK\Samples\C++\Common\Include and (SDK root)\DXSDK\Samples\C++\Common\Src.

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