Introduction to POV-Ray POV-Team for POV-Ray Version 3.6 BETA 2 Contents 1 Introduction 13 1.1 Program Description . 14 1.2 What is Ray-Tracing? . 14 1.3 What is POV-Ray? . 15 1.4 Features . 15 1.5 The Early History of POV-Ray . 16 1.5.1 The Original Creation Message . 18 1.5.2 The Name . 19 1.5.3 A Historic ’Version History’ . 21 1.6 How Do I Begin? . 22 1.7 Notation and Basic Assumptions . 22 2 Getting Started 25 2.1 Our First Image . 25 2.1.1 Understanding POV-Ray’s Coordinate System . 25 2.1.2 Adding Standard Include Files . 27 2.1.3 Adding a Camera . 28 2.1.4 Describing an Object . 28 2.1.5 Adding Texture to an Object . 28 2.1.6 Defining a Light Source . 29 2.2 Basic Shapes . 30 2.2.1 Box Object . 30 2.2.2 Cone Object . 31 2.2.3 Cylinder Object . 31 2.2.4 Plane Object . 31 2.2.5 Torus Object . 32 2.3 CSG Objects . 38 2.3.1 What is CSG? . 38 2.3.2 CSG Union . 38 2.3.3 CSG Intersection . 39 2.3.4 CSG Difference . 40 2.3.5 CSG Merge . 41 2.3.6 CSG Pitfalls . 42 2.4 The Light Source . 42 2.4.1 The Pointlight Source . 43 2.4.2 The Spotlight Source . 44 2.4.3 The Cylindrical Light Source . 45 4 CONTENTS 2.4.4 The Area Light Source . 46 2.4.5 The Ambient Light Source . 47 2.4.6 Light Source Specials . 48 2.5 Simple Texture Options . 50 2.5.1 Surface Finishes . 50 2.5.2 Adding Bumpiness . 50 2.5.3 Creating Color Patterns . 51 2.5.4 Pre-defined Textures . 52 2.6 Using the Camera . 53 2.6.1 Using Focal Blur . 53 2.7 POV-Ray Coordinate System . 54 2.7.1 Transformations . 55 2.7.2 Transformation Order . 58 2.7.3 Inverse Transform . 58 2.7.4 Transform Identifiers . 58 2.7.5 Transforming Textures and Objects . 59 2.8 POV-Ray Options . 60 2.8.1 Command Line Switches . 60 2.8.2 Using INI Files . 61 2.8.3 Using the POVINI Environment Variable . 63 3 Advanced Features 65 3.1 Spline Based Shapes . 65 3.1.1 Lathe Object . 65 3.1.2 Surface of Revolution Object . 74 3.1.3 Prism Object . 75 3.1.4 Sphere Sweep Object . 81 3.1.5 Bicubic Patch Object . 82 3.1.6 Text Object . 87 3.2 Polygon Based Shapes . 91 3.2.1 Mesh Object . 91 3.2.2 Mesh2 Object . 92 3.2.3 Polygon Object . 99 3.3 Other Shapes . 101 3.3.1 Blob Object . 101 3.3.2 Height Field Object . 106 3.3.3 Isosurface Object . 107 3.3.4 Poly Object . 120 3.3.5 Superquadric Ellipsoid Object . 126 3.4 Advanced Texture Options . 129 3.4.1 Pigments . 130 3.4.2 Normals . 135 3.4.3 Finishes . 138 3.4.4 Working With Pigment Maps . 143 3.4.5 Working With Normal Maps . 144 3.4.6 Working With Texture Maps . 145 3.4.7 Working With List Textures . 146 3.4.8 What About Tiles? . 147 3.4.9 Average Function . 147 3.4.10 Working With Layered Textures . 148 CONTENTS 5 3.4.11 When All Else Fails: Material Maps . 154 3.4.12 Limitations Of Special Textures . 156 3.5 Using Atmospheric Effects . 157 3.5.1 The Background . 157 3.5.2 The Sky Sphere . 158 3.5.3 The Fog . 162 3.5.4 The Rainbow . 167 3.6 Radiosity . 171 3.6.1 Introduction . 171 3.6.2 Radiosity with conventional lighting . 172 3.6.3 Radiosity without conventional lighting . 176 3.6.4 Normals and Radiosity . 181 3.6.5 Performance considerations . 182 3.7 Making Animations . 182 3.7.1 The Clock Variable: Key To It All . 182 3.7.2 Clock Dependant Variables And Multi-Stage Animations . 184 3.7.3 The Phase Keyword . 185 3.7.4 Do Not Use Jitter Or Crand . 187 3.7.5 INI File Settings . 187 3.8 While-loop tutorial . 189 3.8.1 What a while-loop is and what it is not . 189 3.8.2 How does a single while-loop work? . 189 3.8.3 How do I make a while-loop? . 190 3.8.4 What is a condition and how do I make one? . 191 3.8.5 What about loop types other than simple for-loops? . 192 3.8.6 What about nested loops? . 193 3.8.7 Mixed-type nested loops . 195 3.8.8 Other things to note . 195 3.9 SDL tutorial: A raytracer . 197 3.9.1 Introduction . 198 3.9.2 The idea and the code . 198 3.9.3 Short introduction to raytracing . 203 3.9.4 Global settings . 204 3.9.5 Scene definition . 205 3.9.6 Initializing the raytracer . 206 3.9.7 Ray-sphere intersection . 207 3.9.8 The Trace macro . 211 3.9.9 Calculating the image . 216 3.9.10 Creating the colored mesh . 216 3.9.11 The Camera-setup . 221 3.10 Isosurface Object . 221 3.10.1 Functions in Isosurface . 222 3.10.2 Transformations on Functions . 224 3.10.3 Combining Functions . 226 3.10.4 Improving Isosurface Speed . 227 4 Questions and Tips 229 4.1 Language Tips and tricks to achieve useful things . 229 4.1.1 How do I make a visible light source? . 229 4.1.2 How do I make bright objects? . 230 6 CONTENTS 4.1.3 How do I move the camera in a circular path? . 230 4.1.4 How do I use an image.