POV-Ray Reference POV-Team for POV-Ray Version 3.6.1 ii Contents 1 Introduction 1 1.1 Notation and Basic Assumptions . 1 1.2 Command-line Options . 2 1.2.1 Animation Options . 3 1.2.2 General Output Options . 6 1.2.3 Display Output Options . 8 1.2.4 File Output Options . 11 1.2.5 Scene Parsing Options . 14 1.2.6 Shell-out to Operating System . 16 1.2.7 Text Output . 20 1.2.8 Tracing Options . 23 2 Scene Description Language 29 2.1 Language Basics . 29 2.1.1 Identifiers and Keywords . 30 2.1.2 Comments . 34 2.1.3 Float Expressions . 35 2.1.4 Vector Expressions . 43 2.1.5 Specifying Colors . 48 2.1.6 User-Defined Functions . 53 2.1.7 Strings . 58 2.1.8 Array Identifiers . 60 2.1.9 Spline Identifiers . 62 2.2 Language Directives . 64 2.2.1 Include Files and the #include Directive . 64 2.2.2 The #declare and #local Directives . 65 2.2.3 File I/O Directives . 68 2.2.4 The #default Directive . 70 2.2.5 The #version Directive . 71 2.2.6 Conditional Directives . 72 2.2.7 User Message Directives . 75 2.2.8 User Defined Macros . 76 3 Scene Settings 81 3.1 Camera . 81 3.1.1 Placing the Camera . 82 3.1.2 Types of Projection . 86 3.1.3 Focal Blur . 88 3.1.4 Camera Ray Perturbation . 89 3.1.5 Camera Identifiers . 89 3.2 Atmospheric Effects . 90 iv CONTENTS 3.2.1 Atmospheric Media . 90 3.2.2 Background . 90 3.2.3 Fog . 91 3.2.4 Sky Sphere . 92 3.2.5 Rainbow . 93 3.3 Global Settings . 94 3.3.1 ADC Bailout . 95 3.3.2 Ambient Light . 95 3.3.3 Assumed Gamma . 96 3.3.4 HF Gray 16...................................... 98 3.3.5 Irid Wavelength . 98 3.3.6 Charset . 99 3.3.7 Max Trace Level................................... 99 3.3.8 Max Intersections . 100 3.3.9 Number Of Waves.................................. 100 3.3.10 Noise generator . 100 3.3.11 Radiosity Basics . 100 3.4 Radiosity . 101 3.4.1 How Radiosity Works . 101 3.4.2 Adjusting Radiosity . 101 3.4.3 Tips on Radiosity . 104 4 Objects 107 4.1 Finite Solid Primitives . 108 4.1.1 Blob . 108 4.1.2 Box . 110 4.1.3 Cone . 111 4.1.4 Cylinder . 112 4.1.5 Height Field . 112 4.1.6 Julia Fractal . 115 4.1.7 Lathe . 117 4.1.8 Prism . 119 4.1.9 Sphere . 121 4.1.10 Sphere Sweep . 121 4.1.11 Superquadric Ellipsoid . 122 4.1.12 Surface of Revolution . 123 4.1.13 Text . 125 4.1.14 Torus . 126 4.2 Finite Patch Primitives . 126 4.2.1 Bicubic Patch . 127 4.2.2 Disc . 128 4.2.3 Mesh . 129 4.2.4 Mesh2 . 130 4.2.5 Polygon . 131 4.2.6 Triangle and Smooth Triangle . 133 4.3 Infinite Solid Primitives . 133 4.3.1 Plane . 134 4.3.2 Poly, Cubic and Quartic . 134 4.3.3 Quadric . 137 4.4 Isosurface Object . 137 4.5 Parametric Object . 139 4.6 Constructive Solid Geometry . 140 4.6.1 Inside and Outside . 141 CONTENTS v 4.6.2 Union . 141 4.6.3 Intersection . 143 4.6.4 Difference . 143 4.6.5 Merge . 144 4.7 Light Sources . ..