LGram16
e067522598
Game client codebase including: - CharacterActionControl: Character and creature management - GlobalScript: Network, items, skills, quests, utilities - RYLClient: Main client application with GUI and event handlers - Engine: 3D rendering engine (RYLGL) - MemoryManager: Custom memory allocation - Library: Third-party dependencies (DirectX, boost, etc.) - Tools: Development utilities 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
76 lines
3.5 KiB
Plaintext
76 lines
3.5 KiB
Plaintext
//-----------------------------------------------------------------------------
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// Name: ShadowVolume Direct3D Sample
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//
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// Copyright (c) 1998-2001 Microsoft Corporation. All rights reserved.
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//-----------------------------------------------------------------------------
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Description
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===========
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The ShadowVolume sample uses stencil buffers to implement real-time shadows.
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In the sample, a complex object is rendered and used as a shadow-caster, to
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cast real-time shadows on itself and on the terrain below.
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Stencil buffers are a depth buffer technique that can be updated as
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geometry is rendered, and used again as a mask for drawing more geometry.
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Common effects include mirrors, shadows (an advanced technique), dissolves,
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etc..
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Note that not all cards support all features for all the various stencil
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buffer techniques (some hardware has no, or limited, stencil buffer
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support). For more information on stencil buffers, refer to the DirectX SDK
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documentation.
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Path
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====
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Source: DXSDK\Samples\Multimedia\D3D\StencilBuffer\ShadowVolume
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Executable: DXSDK\Samples\Multimedia\D3D\Bin
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User's Guide
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============
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The following keys are implemented. The dropdown menus can be used for the
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same controls.
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<Enter> Starts and stops the scene
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<Space> Advances the scene by a small increment
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<F1> Shows help or available commands.
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<F2> Prompts user to select a new rendering device or display mode
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<Alt+Enter> Toggles between fullscreen and windowed modes
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<Esc> Exits the app.
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Programming Notes
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=================
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Real-time shadows is a fairly advanced technique. Each frame, or as the
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geometry or lights in the scene are moves, an object called a shadow volume
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is computed. A shadow volume is an actual 3D object which is the siholuette
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of the shadowcasting object, as pretruded away from the light source.
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In this sample, the 3D object which casts shadows is a bi-plane. Each frame,
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the sihlouette of the plane is computed (using an edge detection algorithm,
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in which sihlouette edges are found because the normals of adjacent polygons
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will have opposing normals with respect to the light vector). The resulting
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edge list (the sihlouette) is pretuded into a 3D object away from the light
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source. This 3D object is known as the shadow volume, as everypoint inside
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the volume is inside a shadow.
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Next, the shadow volume is rendering into the stencil buffer twice. First,
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only forward-facing polygons are rendering, and the stencil buffer values
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are incremented each time. Then the back-facing polygons of the shadow
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volume are drawm, decrementing values in the stencil buffer. Normally, all
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incremented and decremented values would cancel each other out. However,
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because the scene was already rendered with normal geometry (the plane and
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the terrain, in this case), some pixels will fail the zbuffer test as the
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shadowvolume is rendered. Any values left in the stencil buffer correspond
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to pixels that are in the shadow.
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Finally, these remaining stencil buffer contents are used as a mask, as a
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large all-encompassing black quad is alpha-blended into the scene. With the
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stencil buffer as a mask, only pixels in shadow are darkened
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This sample makes use of common DirectX code (consisting of helper functions,
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etc.) that is shared with other samples on the DirectX SDK. All common
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headers and source code can be found in the following directory:
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DXSDK\Samples\Multimedia\Common
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