Introduction to POV-Ray

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Introduction to POV-Ray POV-Team for POV-Ray Version 3.6.1 ii Contents 1 Introduction 1 1.1 Program Description . 2 1.2 What is Ray-Tracing? . 2 1.3 What is POV-Ray? . 2 1.4 Features . 3 1.5 The Early History of POV-Ray . 3 1.5.1 The Original Creation Message . 5 1.5.2 The Name . 6 1.5.3 A Historic ’Version History’ . 7 1.6 How Do I Begin? . 8 1.7 Notation and Basic Assumptions . 9 2 Getting Started 11 2.1 Our First Image . 11 2.1.1 Understanding POV-Ray’s Coordinate System . 11 2.1.2 Adding Standard Include Files . 12 2.1.3 Adding a Camera . 13 2.1.4 Describing an Object . 13 2.1.5 Adding Texture to an Object . 14 2.1.6 Defining a Light Source . 14 2.2 Basic Shapes . 15 2.2.1 Box Object . 15 2.2.2 Cone Object . 16 2.2.3 Cylinder Object . 16 2.2.4 Plane Object . 16 2.2.5 Torus Object . 17 2.3 CSG Objects . 22 2.3.1 What is CSG? . 22 2.3.2 CSG Union . 22 2.3.3 CSG Intersection . 23 2.3.4 CSG Difference . 24 2.3.5 CSG Merge . 25 2.3.6 CSG Pitfalls . 26 2.4 The Light Source . 26 2.4.1 The Pointlight Source . 26 2.4.2 The Spotlight Source . 28 2.4.3 The Cylindrical Light Source . 29 2.4.4 The Area Light Source . 29 2.4.5 The Ambient Light Source . 30 2.4.6 Light Source Specials . 31 2.5 Simple Texture Options . 33 iv CONTENTS 2.5.1 Surface Finishes . 33 2.5.2 Adding Bumpiness . 33 2.5.3 Creating Color Patterns . 33 2.5.4 Pre-defined Textures . 34 2.6 Using the Camera . 35 2.6.1 Using Focal Blur . 35 2.7 POV-Ray Coordinate System . 37 2.7.1 Transformations . 37 2.7.2 Transformation Order . 39 2.7.3 Inverse Transform . 39 2.7.4 Transform Identifiers . 40 2.7.5 Transforming Textures and Objects . 40 2.8 Setting POV-Ray Options . 41 2.8.1 Command Line Switches . 41 2.8.2 Using INI Files . 42 2.8.3 Using the POVINI Environment Variable . 43 3 Advanced Features 45 3.1 Spline Based Shapes . 45 3.1.1 Lathe Object . 45 3.1.2 Surface of Revolution Object . 52 3.1.3 Prism Object . 54 3.1.4 Sphere Sweep Object . 59 3.1.5 Bicubic Patch Object . 60 3.1.6 Text Object . 65 3.2 Polygon Based Shapes . 67 3.2.1 Mesh Object . 67 3.2.2 Mesh2 Object . 69 3.2.3 Polygon Object . 75 3.3 Other Shapes . 77 3.3.1 Blob Object . 77 3.3.2 Height Field Object . 81 3.3.3 Isosurface Object . 83 3.3.4 Poly Object . 97 3.3.5 Superquadric Ellipsoid Object . 103 3.4 Advanced Texture Options . 106 3.4.1 Pigments . 106 3.4.2 Normals . 111 3.4.3 Finishes . 113 3.4.4 Working With Pigment Maps . 118 3.4.5 Working With Normal Maps . 119 3.4.6 Working With Texture Maps . 119 3.4.7 Working With List Textures . 120 3.4.8 What About Tiles? . 121 3.4.9 Average Function . 121 3.4.10 Working With Layered Textures . 122 3.4.11 When All Else Fails: Material Maps . 127 3.4.12 Limitations Of Special Textures . 129 3.5 Using Atmospheric Effects . 130 3.5.1 The Background . 130 3.5.2 The Sky Sphere . 131 3.5.3 The Fog . 134 3.5.4 The Rainbow . 139 CONTENTS v 3.6 Simple Media Tutorial . 143 3.6.1 Types of media . 143 3.6.2 Some media concepts . ..

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Photon Mapping Assignment
Photon Mapping Assignment 15-864 Advanced Computer Graphics, Carnegie Mellon University Instructor: Doug L. James TA: Christopher Twigg Introduction sampling to emit photons of equal intensity from the diffuse area light source. Use the ray tracer’s functionality to propagate photons In this assignment you will implement (portions of) a photon map- (reflect, transmit and absorb) throughout the scene. To maintain ping renderer. For simplicity, we will only consider scenes with a photons of similar intensity, use Russian roulette [Arvo and Kirk single area light source, and assume surfaces are diffuse, or purely 1990] to determine if photons are absorbed (diffuse), transmitted specular (e.g., mirror or glass). To generate images for testing and (transparent), or reflected at surfaces. Use Schlick’s approximation grading, a test scene will be provided for you on the class website; to Fresnel’s specular reflection coefficient to determine the prob- this will be a very simple consisting of the Cornell box, an area ability of transmission and reflection at specular interfaces, e.g., light source, and specular spheres. Although a brief explanation of glass. Store the photons in the photon map using Jensen’s kd-tree what needs to be done is given below, further implementation de- data structure implementation (provided on the web page). Once tails can be found in [Jensen 2001; Jensen 1996], as well as other these photons are stored, the data structure can compute the filtered ray tracing [Shirley 2000], Monte Carlo [Jensen 2003], and global irradiance estimates you need later. illumination texts [Dutre´ et al. 2003]. Build the Caustic Photon Map (20 points): The high- Getting Started: Familiarize yourself with resolution caustic photon map represents the LS+D paths, and it the ray tracer is therefore only necessary to emit photons toward specular objects when computing the caustic photon map.
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Seamless Texture Mapping of 3D Point Clouds
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Texture Mapping There Are Limits to Geometric Modeling
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2014 3-4 Acta Graphica.Indd
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The Photon Mapping Method
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