This topic pertains only to application development in C++. See Direct3D Immediate Mode Visual Basic Samples.

Description

The ShadowVol sample shows how to create and use stencil buffers to implement shadow volumes. With shadow volumes, an object of any shape can cast a shadow onto another object of any shape.

Path

Source: (SDK root)\Samples\Multimedia\D3dim\Src\ShadowVol

Executable: (SDK root)\Samples\Multimedia\D3dim\Shadowvol.exe

User's Guide

This sample runs only on devices that support stencil buffers.

Press F1 to see available commands, or choose from the menu.

Programming Notes

Shadow volumes are a fairly advanced technique.

To create shadow volumes

1. Build a set of polygonal faces that encompass the volume of the shadow.
2. Use the stencil buffer to render the front-facing planes of the shadow volume.
3. Set up the stencil buffer to render the back-facing planes, this time subtracting values from the stencil buffer. The stencil buffer then contains a mask of the cast shadow.
4. Draw a large gray or black rectangle, using the stencil buffer as a mask, and the frame buffer will be updated with the shadow.