POM.rar_POM_Parallax_Reducing Polygons_occlusion_parallax map ga

1 //-------------------------------------------------------------------------------------- 2 // File: ParallaxOcclusionMapping.fx 3 // 4 // Parallax occlusion mapping implementation 5 // 6 // Implementation of the algorithm as described in "Dynamic Parallax Occlusion 7 // Mapping with Approximate Soft Shadows" paper, by N. Tatarchuk, ATI Research, 8 // to appear in the proceedings of ACM Symposium on Interactive 3D Graphics and Games, 2006. 9 // 10 // For examples of use in a real-time scene, see ATI X1K demo "ToyShop": 11 // http://www.ati.com/developer/demos/rx1800.html 12 // 13 // Copyright (c) ATI Research, Inc. All rights reserved. 14 //-------------------------------------------------------------------------------------- 15 16 //-------------------------------------------------------------------------------------- 17 // Global variables 18 //-------------------------------------------------------------------------------------- 19 20 texture g_baseTexture; // Base color texture 21 texture g_nmhTexture; // Normal map and height map texture pair 22 23 float4 g_materialAmbientColor; // Material's ambient color 24 float4 g_materialDiffuseColor; // Material's diffuse color 25 float4 g_materialSpecularColor; // Material's specular color 26 27 float g_fSpecularExponent; // Material's specular exponent 28 bool g_bAddSpecular; // Toggles rendering with specular or without 29 30 // Light parameters: 31 float3 g_LightDir; // Light's direction in world space 32 float4 g_LightDiffuse; // Light's diffuse color 33 float4 g_LightAmbient; // Light's ambient color 34 35 float4 g_vEye; // Camera's location 36 float g_fBaseTextureRepeat; // The tiling factor for base and normal map textures 37 float g_fHeightMapScale; // Describes the useful range of values for the height field 38 39 // Matrices: 40 float4x4 g_mWorld; // World matrix for object 41 float4x4 g_mWorldViewProjection; // World * View * Projection matrix 42 float4x4 g_mView; // View matrix 43 44 bool g_bVisualizeLOD; // Toggles visualization of level of detail colors 45 bool g_bVisualizeMipLevel; // Toggles visualization of mip level 46 bool g_bDisplayShadows; // Toggles display of self-occlusion based shadows 47 48 float2 g_vTextureDims; // Specifies texture dimensions for computation of mip level at 49 // render time (width, height) 50 51 int g_nLODThreshold; // The mip level id for transitioning between the full computation 52 // for parallax occlusion mapping and the bump mapping computation 53 54 float g_fShadowSoftening; // Blurring factor for the soft shadows computation 55 56 int g_nMinSamples; // The minimum number of samples for sampling the height field profile 57 int g_nMaxSamples; // The maximum number of samples for sampling the height field profile 58 59 60 61 //-------------------------------------------------------------------------------------- 62 // Texture samplers 63 //-------------------------------------------------------------------------------------- 64 sampler tBase = 65 sampler_state 66 { 67 Texture = < g_baseTexture >; 68 MipFilter = LINEAR; 69 MinFilter = LINEAR; 70 MagFilter = LINEAR; 71 }; 72 sampler tNormalHeightMap = 73 sampler_state 74 { 75 Texture = < g_nmhTexture >; 76 MipFilter = LINEAR; 77 MinFilter = LINEAR; 78 MagFilter = LINEAR; 79 }; 80 81 82 //-------------------------------------------------------------------------------------- 83 // Vertex shader output structure 84 //-------------------------------------------------------------------------------------- 85 struct VS_OUTPUT 86 { 87 float4 position : POSITION; 88 float2 texCoord : TEXCOORD0; 89 float3 vLightTS : TEXCOORD1; // light vector in tangent space, denormalized 90 float3 vViewTS : TEXCOORD2; // view vector in tangent space, denormalized 91 float2 vParallaxOffsetTS : TEXCOORD3; // Parallax offset vector in tangent space 92 float3 vNormalWS : TEXCOORD4; // Normal vector in world space 93 float3 vViewWS : TEXCOORD5; // View vector in world space 94 95 }; 96 97 98 //-------------------------------------------------------------------------------------- 99 // This shader computes standard transform and lighting 100 //-------------------------------------------------------------------------------------- 101 VS_OUTPUT RenderSceneVS( float4 inPositionOS : POSITION, 102 float2 inTexCoord : TEXCOORD0, 103 float3 vInNormalOS : NORMAL, 104 float3 vInBinormalOS : BINORMAL, 105 float3 vInTangentOS : TANGENT ) 106 { 107 VS_OUTPUT Out; 108 109 // Transform and output input position 110 Out.position = mul( inPositionOS, g_mWorldViewProjection ); 111 112 // Propagate texture coordinate through: 113 Out.texCoord = inTexCoord * g_fBaseTextureRepeat; 114 115 // Transform the normal, tangent and binormal vectors from object space to homogeneous projection space: 116 float3 vNormalWS = mul( vInNormalOS, (float3x3) g_mWorld ); 117 float3 vTangentWS = mul( vInTangentOS, (float3x3) g_mWorld ); 118 float3 vBinormalWS = mul( vInBinormalOS, (float3x3) g_mWorld ); 119 120 // Propagate the world space vertex normal through: 121 Out.vNormalWS = vNormalWS; 122 vNormalWS = normalize( vNormalWS ); 123 vTangentWS = normalize( vTangentWS ); 124 vBinormalWS = normalize( vBinormalWS ); 125 126 // Compute position in world space: 127 float4 vPositionWS = mul( inPositionOS, g_mWorld ); 128 129 // Compute and output the world view vector (unnormalized): 130 float3 vViewWS = g_vEye - vPositionWS; 131 Out.vViewWS = vViewWS; 132 133 // Compute denormalized light vector in world space: 134 float3 vLightWS = g_LightDir; 135 136 // Normalize the light and view vectors and transform it to the tangent space: 137 float3x3 mWorldToTangent = float3x3( vTangentWS, vBinormalWS, vNormalWS ); 138 139 // Propagate the view and the light vectors (in tangent space): 140 Out.vLightTS = mul( vLightWS, mWorldToTangent ); 141 Out.vViewTS = mul( mWorldToTangent, vViewWS ); 142 143 // Compute the ray direction for intersecting the height field profile with 144 // current view ray. See the above paper for derivation of this computation. 145 146 // Compute initial parallax displacement direction: 147 float2 vParallaxDirection = normalize( Out.vViewTS.xy ); 148 149 // The length of this vector determines the furthest amount of displacement: 150 float fLength = length( Out.vViewTS ); 151 float fParallaxLength = sqrt( fLength * fLength - Out.vViewTS.z * Out.vViewTS.z ) / Out.vViewTS.z; 152 153 // Compute the actual reverse parallax displacement vector: