Lecture 19: All Together with Refraction
|
|
- Joanna Gray
- 5 years ago
- Views:
Transcription
1 Lecture 19: All Together with Refraction December 1, /1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 1
2 How about Interreflections? Note reflections Granite tabletop Visible on base Also on handle This is a featured picture on the English language Wikipedia (Featured pictures) and is considered one of the finest images. (October 2012) 12/1/16 Bruce Draper & J. Ross Beveridge 2
3 Rationale for Interreflections Not all the light striking a surface comes directly from a light source. Some reflects off one surface onto another. We ignore diffuse reflected light: Because its small, and we can get away with it Because it is very expensive to compute Specular reflection much more sensitive Just consider reflections in previous image. 12/1/16 Bruce Draper & J. Ross Beveridge 3
4 Interreflections v L In the case of mirrors or shiny objects, this can have a major impact 12/1/16 Bruce Draper & J. Ross Beveridge 4
5 Illustrating Recursive Ray Tracing V R L L L N L N poi V V R L R L V R R L R L poi 12/1/16 Bruce Draper & J. Ross Beveridge 5
6 You have a full working illustration! 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 6
7 In 3D locate Focal Point Image Plane Objects Light 1 Light 2 3D Scene Layout 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 7
8 Rays of Reflection To add reflections, we need the light hitting the surface from the reflected viewing ray. R V L T N T R L V C q q S Multiply reflected illumination by k r and add to total illumination. 12/1/16 Bruce Draper & J. Ross Beveridge 8
9 Computing V R R V = 2(V N)N-V Just like R L, but V replaces L To be more detailed N T V N V = (V N)N T V = N V V = (V N)N V R V = V + 2T V = 2(V N)N-V R V S V 12/1/16 Bruce Draper & J. Ross Beveridge 9
10 The Same Thing in Code From the notebook refr = make_unit((2*np.dot(n,uinv)*n)-uinv) Includes: Function to make result unit length The numpy dot product function The surface normal The ray pointing back the way the original ray came into the surface namely U inverse 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 10
11 Example Code with Recursion There is a lot more going on in this code, study it and play with it until you understand each line; Why is it there? What does it do? 12/1/16 Bruce Draper & J. Ross Beveridge 11
12 Complications that Arise Is the reflection `colored by the material Notebook example uses K r Other systems may use the diffuse coeficients. Is anything lost through bounces? Does bouncing light from surface to surface take away energy? (Yes). So in code there should be an attenuation term. This is set to 0.9 in all the Notebook examples. 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 12
13 Translucence Some light passes through the material. Typically, passed through light gets the diffuse reflection properties of the surface, unless object is 100% translucent (i.e. transparent) Speed of light is a function of the medium This causes light to bend at boundaries example: looking at the bottom of a pool 12/1/16 Bruce Draper & J. Ross Beveridge 13
14 Refraction - With Trigonomety Key is Snell s law sin( θ t )= η i sin θ i η t θ i angle of incidence θ r angle of refraction η i index of refraction material #1 η t index of refraction material #2 ( ) W θ i N θ i R The refraction ray is: " T = η i $ cos θ i # η t ( ) cos( θ t ) % 'N η i W & η t θ t T 12/1/16 Bruce Draper & J. Ross Beveridge 14
15 Practical Refraction: Solids When light enters a solid glass object? h air = 1.0 h glass = 1.5 N W Theta i Sin mu Theta r " θ r = sin 1 η $ i sin θ i # η r ( ) % ' = sin 1 & ( 0.67 sin( θ i )) 12/1/16 Bruce Draper & J. Ross Beveridge 15
16 More Recursion This changes ray tracing from tail-recursion to double-recursion light1 light2 N N camera This is the recursive Refraction ray light3 12/1/16 Bruce Draper & J. Ross Beveridge 16
17 Practical Refraction: Surfaces What happens as it passes through a solid or surface? sinθ 1 = η i η r sinθ i sinθ i = η r η i sinθ 2 sinθ 1 = η i η r η r η i sinθ 2 = sinθ 2 Ø Overall effect: displacement of the incident vector Note: this assumes the two surfaces of the solid are coplanar! 12/1/16 Bruce Draper & J. Ross Beveridge 17
18 Refraction - No Trigonometry. First Constraint: Snells Law T = αw + βn sin( θ i ) 2 µ 2 = sin( θ t ) 2 µ = µ i µ t ( 1 cos( θ i ) 2 ) µ 2 =1 cos( θ t ) 2 W θ i N θ i R ( 1 ( W N) 2 ) µ 2 =1 ( N T ) 2 ( 1 ( W N) 2 ) µ 2 =1 N ( αw + βn) ( ) 2 -N θ t T 12/1/16 Bruce Draper & J. Ross Beveridge 18
19 Refraction - No Trigonometry Second Constraint: Refraction ray is unit length. T T = αw + βn ( ) αw + βn ( ) =1 = α 2 + 2αβ W N ( ) + β 2 =1 Two quadratic equations in two unknowns. Solving is a bit involved, next slide & writeup. Here is the answer. α = µ β = µ ( W N) 1 µ 2 + µ 2 ( W N) 2 12/1/16 Bruce Draper & J. Ross Beveridge 19
20 A Wonderful Real Example Yes, refraction typically makes everthing upside down and backwards. 12/1/16 Bruce Draper & J. Ross Beveridge 20
21 Refraction and Polygons It is entirely possible to implement refraction through complex solid models defined by polygons. But! Doing so requires the following: Models must be complete: no holes! All faces (triangles) must be tagged to a solid. Needed to find where refraction ray exits the solid. There is a simpler special case Thin faces with parallel sides (next slide). 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 21
22 Special Case: Thin Faces Consider entrance and exit The are parallel (see picture) Refraction vectors Pass through at a shifted angle But exit in the same direction Result is an offset only Offset depends on index of refraction Offset depends on the thickness of the face 12/1/16 Bruce Draper & J. Ross Beveridge 22
23 Double Recursion With refraction, ray tracing changes from tail-recursion to double recursion light1 light2 N N camera light3 This is the recursive refraction ray 12/1/16 Bruce Draper & J. Ross Beveridge 23
24 12/1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 24
25 Semester Wrap Up If you understand every line of code in the Sage Notebook creating this image you have covered a good portion of what is needed to have succeeded in CS /1/16 CSU CS410 Fall 2016, Ross Beveridge & Bruce Draper 25
Reflection and Refraction
Reflection and Refraction Lecture #22 Tuesday, ovember 19, 2013 (Major Updates 12/06/13) How about Interreflections ote reflections Granite tabletop Visible on base Also on handle This is a featured picture
More informationReflection and Refraction
Reflection and Refraction Lecture #21 Tuesday, ovember 18, 2014 How about Interreflections! ote reflections! Granite tabletop! Visible on base! Also on handle This is a featured picture on the English
More informationLecture 17: Recursive Ray Tracing. Where is the way where light dwelleth? Job 38:19
Lecture 17: Recursive Ray Tracing Where is the way where light dwelleth? Job 38:19 1. Raster Graphics Typical graphics terminals today are raster displays. A raster display renders a picture scan line
More information1. What is the law of reflection?
Name: Skill Sheet 7.A The Law of Reflection The law of reflection works perfectly with light and the smooth surface of a mirror. However, you can apply this law to other situations. For example, how would
More informationTurn on the Lights: Reflectance
Turn on the Lights: Reflectance Part 2: Shading Tuesday, October 15 2012 Lecture #14 Goal of Shading Model simple light sources Point light sources Extended light sources Ambient lighting Model lighting
More informationRay-Tracing. Misha Kazhdan
Ray-Tracing Misha Kazhdan Ray-Tracing In graphics, we often represent the surface of a 3D shape by a set of triangles. Goal: Ray-Tracing Take a collection of triangles representing a 3D scene and render
More informationLecture 10: Ray tracing
Interactive Computer Graphics Lecture 10: Ray tracing Graphics Lecture 10: Slide 1 Some slides adopted from H. Pfister, Harvard Graphics Lecture 10: Slide 2 Direct and Global Illumination Direct illumination:
More informationOutline The Refraction of Light Forming Images with a Plane Mirror 26-3 Spherical Mirror 26-4 Ray Tracing and the Mirror Equation
Chapter 6 Geometrical Optics Outline 6-1 The Reflection of Light 6- Forming Images with a Plane Mirror 6-3 Spherical Mirror 6-4 Ray Tracing and the Mirror Equation 6-5 The Refraction of Light 6-6 Ray Tracing
More informationAlgebra Based Physics
Slide 1 / 66 Slide 2 / 66 Algebra Based Physics Geometric Optics 2015-12-01 www.njctl.org Table of ontents Slide 3 / 66 lick on the topic to go to that section Reflection Spherical Mirror Refraction and
More informationReflection & refraction
2015 EdExcel A Level Physics 2015 EdExcel A Level Physics Topic Topic 5 5 Reflection & refraction Reflection revision Reflection is the bouncing of light rays off a surface Reflection from a mirror: Normal
More informationOverview: Ray Tracing & The Perspective Projection Pipeline
Overview: Ray Tracing & The Perspective Projection Pipeline Lecture #2 Thursday, August 28 2014 About this Lecture! This is an overview.! Think of it as a quick tour moving fast.! Some parts, e.g. math,
More informationSo far, we have considered only local models of illumination; they only account for incident light coming directly from the light sources.
11 11.1 Basics So far, we have considered only local models of illumination; they only account for incident light coming directly from the light sources. Global models include incident light that arrives
More informationSupplement to Lecture 16
Supplement to Lecture 16 Global Illumination: View Dependent CS 354 Computer Graphics http://www.cs.utexas.edu/~bajaj/ Notes and figures from Ed Angel: Interactive Computer Graphics, 6 th Ed., 2012 Addison
More informationRecursive Ray Tracing. Ron Goldman Department of Computer Science Rice University
Recursive Ray Tracing Ron Goldman Department of Computer Science Rice University Setup 1. Eye Point 2. Viewing Screen 3. Light Sources 4. Objects in Scene a. Reflectivity b. Transparency c. Index of Refraction
More informationPhysics 1C. Lecture 25B. "There are two ways of spreading light: to be the candle or the mirror that reflects it." --Edith Wharton
Physics 1C Lecture 25B "There are two ways of spreading light: to be the candle or the mirror that reflects it." --Edith Wharton Refraction of Light When light passes from one medium to another, it is
More informationLighting and Shading
Lighting and Shading Today: Local Illumination Solving the rendering equation is too expensive First do local illumination Then hack in reflections and shadows Local Shading: Notation light intensity in,
More informationChapter 26 Geometrical Optics
Chapter 26 Geometrical Optics 26.1 The Reflection of Light 26.2 Forming Images With a Plane Mirror 26.3 Spherical Mirrors 26.4 Ray Tracing and the Mirror Equation 26.5 The Refraction of Light 26.6 Ray
More informationCOMP371 COMPUTER GRAPHICS
COMP371 COMPUTER GRAPHICS SESSION 15 RAY TRACING 1 Announcements Programming Assignment 3 out today - overview @ end of the class Ray Tracing 2 Lecture Overview Review of last class Ray Tracing 3 Local
More informationChapter 18 Ray Optics
Chapter 18 Ray Optics Chapter Goal: To understand and apply the ray model of light. Slide 18-1 Chapter 18 Preview Looking Ahead Text p. 565 Slide 18-2 Wavefronts and Rays When visible light or other electromagnetic
More informationCS 428: Fall Introduction to. Raytracing. Andrew Nealen, Rutgers, /18/2009 1
CS 428: Fall 2009 Introduction to Computer Graphics Raytracing 11/18/2009 1 Forward ray tracing From the light sources Simulate light transport one ray at a time Rays start from lights + bounce around
More informationLecture 7 Notes: 07 / 11. Reflection and refraction
Lecture 7 Notes: 07 / 11 Reflection and refraction When an electromagnetic wave, such as light, encounters the surface of a medium, some of it is reflected off the surface, while some crosses the boundary
More informationIntroduction Ray tracing basics Advanced topics (shading) Advanced topics (geometry) Graphics 2010/2011, 4th quarter. Lecture 11: Ray tracing
Lecture 11 Ray tracing Introduction Projection vs. ray tracing Projection Ray tracing Rendering Projection vs. ray tracing Projection Ray tracing Basic methods for image generation Major areas of computer
More informationLIGHT. Speed of light Law of Reflection Refraction Snell s Law Mirrors Lenses
LIGHT Speed of light Law of Reflection Refraction Snell s Law Mirrors Lenses Light = Electromagnetic Wave Requires No Medium to Travel Oscillating Electric and Magnetic Field Travel at the speed of light
More informationCS 325 Computer Graphics
CS 325 Computer Graphics 04 / 02 / 2012 Instructor: Michael Eckmann Today s Topics Questions? Comments? Illumination modelling Ambient, Diffuse, Specular Reflection Surface Rendering / Shading models Flat
More informationRay Tracing. CSCI 420 Computer Graphics Lecture 15. Ray Casting Shadow Rays Reflection and Transmission [Ch ]
CSCI 420 Computer Graphics Lecture 15 Ray Tracing Ray Casting Shadow Rays Reflection and Transmission [Ch. 13.2-13.3] Jernej Barbic University of Southern California 1 Local Illumination Object illuminations
More informationCOMP30019 Graphics and Interaction Ray Tracing
COMP30019 Graphics and Interaction Ray Tracing Department of Computer Science and Software Engineering The Lecture outline Ray tracing Recursive Ray Tracing Binary Space Partition (BSP) Trees Refraction
More information11.2 Refraction. December 10, Wednesday, 11 December, 13
11.2 Refraction December 10, 2013. Refraction Light bends when it passes from one medium (material) to another this bending is called refraction this is because the speed of light changes The Speed of
More informationLecture 14: Refraction
Lecture 14: Refraction We know from experience that there are several transparent substances through which light can travel air, water, and glass are three examples When light passes from one such medium
More informationPhotorealism: Ray Tracing
Photorealism: Ray Tracing Reading Assignment: Chapter 13 Local vs. Global Illumination Local Illumination depends on local object and light sources only Global Illumination at a point can depend on any
More informationAt the interface between two materials, where light can be reflected or refracted. Within a material, where the light can be scattered or absorbed.
At the interface between two materials, where light can be reflected or refracted. Within a material, where the light can be scattered or absorbed. The eye sees by focusing a diverging bundle of rays from
More informationPhysics 1C, Summer 2011 (Session 1) Practice Midterm 2 (50+4 points) Solutions
Physics 1C, Summer 2011 (Session 1) Practice Midterm 2 (50+4 points) s Problem 1 (5x2 = 10 points) Label the following statements as True or False, with a one- or two-sentence explanation for why you chose
More informationLecture Ray Model of Light. Physics Help Q&A: tutor.leiacademy.org
Lecture 1201 Ray Model of Light Physics Help Q&A: tutor.leiacademy.org Reflection of Light A ray of light, the incident ray, travels in a medium. When it encounters a boundary with a second medium, part
More informationComputer Graphics. Ray Tracing. Based on slides by Dianna Xu, Bryn Mawr College
Computer Graphics Ray Tracing Based on slides by Dianna Xu, Bryn Mawr College Ray Tracing Example Created by Anto Matkovic Ray Tracing Example Ray Tracing Example Ray Tracing Most light rays do not reach
More informationIllumination. Courtesy of Adam Finkelstein, Princeton University
llumination Courtesy of Adam Finkelstein, Princeton University Ray Casting mage RayCast(Camera camera, Scene scene, int width, int height) { mage image = new mage(width, height); for (int i = 0; i < width;
More informationGeneral Physics II. Mirrors & Lenses
General Physics II Mirrors & Lenses Nothing New! For the next several lectures we will be studying geometrical optics. You already know the fundamentals of what is going on!!! Reflection: θ 1 = θ r incident
More informationRendering Part I (Basics & Ray tracing) Lecture 25 December 1, 2015
Rendering Part I (Basics & Ray tracing) Lecture 25 December 1, 2015 What is rendering? Generating an image from a 3D scene model Ingredients Representation of 3D geometry Specification for camera & lights
More informationPHYSICS. Chapter 34 Lecture FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E RANDALL D. KNIGHT
PHYSICS FOR SCIENTISTS AND ENGINEERS A STRATEGIC APPROACH 4/E Chapter 34 Lecture RANDALL D. KNIGHT Chapter 34 Ray Optics IN THIS CHAPTER, you will learn about and apply the ray model of light Slide 34-2
More informationChapter 26 Geometrical Optics
Chapter 26 Geometrical Optics The Reflection of Light: Mirrors: Mirrors produce images because the light that strikes them is reflected, rather than absorbed. Reflected light does much more than produce
More informationToday s Topic: Refraction / Snell s Law
Today s Topic: Refraction / Snell s Law Learning Goal: Students will be able to calculate the angle of reflection of a bent light wave. Take out your notes from yesterday as we learn about Snell s Law.
More informationProblem Set 4 Part 1 CMSC 427 Distributed: Thursday, November 1, 2007 Due: Tuesday, November 20, 2007
Problem Set 4 Part 1 CMSC 427 Distributed: Thursday, November 1, 2007 Due: Tuesday, November 20, 2007 Programming For this assignment you will write a simple ray tracer. It will be written in C++ without
More informationChapter 12 Notes: Optics
Chapter 12 Notes: Optics How can the paths traveled by light rays be rearranged in order to form images? In this chapter we will consider just one form of electromagnetic wave: visible light. We will be
More informationOptics: Laser Light Show Student Advanced Version
Optics: Laser Light Show Student Advanced Version In this lab, you will explore the behavior of light. You will observe reflection and refraction of a laser beam in jello, and use a diffraction pattern
More informationREFLECTION & REFRACTION
REFLECTION & REFRACTION OBJECTIVE: To study and verify the laws of reflection and refraction using a plane mirror and a glass block. To see the virtual images that can be formed by the reflection and refraction
More informationExperiment 7 Geometric Optics
Physics 263 Experiment 7 Geometric Optics In this laboratory, we will perform several experiments on geometric optics. A pictorial diagram of the various components to be used is shown in Figure 5. 1 Refraction
More informationReflections. I feel pretty, oh so pretty
Reflections I feel pretty, oh so pretty Objectives By the end of the lesson, you should be able to: Draw an accurate reflective angle Determine the focal length of a spherical mirror Light Review Light
More informationReflection and Refraction
rev 05/2018 Equipment List and Refraction Qty Items Part Numbers 1 Light Source, Basic Optics OS-8517 1 Ray Optics Set OS-8516 2 White paper, sheet 1 Metric ruler 1 Protractor Introduction The purpose
More informationRecall: Basic Ray Tracer
1 Recall: Ray Tracing Generate an image by backwards tracing the path of light through pixels on an image plane Simulate the interaction of light with objects Recall: Basic Ray Tracer Trace a primary ray
More informationPhysics 102: Lecture 17 Reflection and Refraction of Light
Physics 102: Lecture 17 Reflection and Refraction of Light Physics 102: Lecture 17, Slide 1 Recall from last time. Today Last Time Reflection: θ i = θ r Flat Mirror: image equidistant behind Spherical
More informationAll forms of EM waves travel at the speed of light in a vacuum = 3.00 x 10 8 m/s This speed is constant in air as well
Pre AP Physics Light & Optics Chapters 14-16 Light is an electromagnetic wave Electromagnetic waves: Oscillating electric and magnetic fields that are perpendicular to the direction the wave moves Difference
More informationChapter 5 Mirrors and Lenses
Chapter 5 Notes: Mirrors and Lenses Name: Block: The Ray Model of Light The ray model of light represents light as a line, or ray, indicating the path of a beam of light. Light travels in straight lines
More informationLight: Geometric Optics
Light: Geometric Optics 23.1 The Ray Model of Light Light very often travels in straight lines. We represent light using rays, which are straight lines emanating from an object. This is an idealization,
More informationHome Lab 7 Refraction, Ray Tracing, and Snell s Law
Home Lab Week 7 Refraction, Ray Tracing, and Snell s Law Home Lab 7 Refraction, Ray Tracing, and Snell s Law Activity 7-1: Snell s Law Objective: Verify Snell s law Materials Included: Laser pointer Cylindrical
More informationOptics Course (Phys 311) Geometrical Optics Refraction through Lenses
Optics Course (Phys ) Geometrical Optics Refraction through Lenses Lecturer: Dr Zeina Hashim Slide 1 Objectives covered in this lesson : 1. Refraction through single spherical refracting surfaces. 2. Lenses:
More informationComp 410/510 Computer Graphics. Spring Shading
Comp 410/510 Computer Graphics Spring 2017 Shading Why we need shading Suppose we build a model of a sphere using many polygons and then color it using a fixed color. We get something like But we rather
More informationDispersion (23.5) Neil Alberding (SFU Physics) Physics 121: Optics, Electricity & Magnetism Spring / 17
Neil Alberding (SFU Physics) Physics 121: Optics, Electricity & Magnetism Spring 2010 1 / 17 Dispersion (23.5) The speed of light in a material depends on its wavelength White light is a mixture of wavelengths
More informationLecture 11: Ray tracing (cont.)
Interactive Computer Graphics Ray tracing - Summary Lecture 11: Ray tracing (cont.) Graphics Lecture 10: Slide 1 Some slides adopted from H. Pfister, Harvard Graphics Lecture 10: Slide 2 Ray tracing -
More informationI have a meeting with Peter Lee and Bob Cosgrove on Wednesday to discuss the future of the cluster. Computer Graphics
Announcements Assignment 4 will be out later today Problem Set 3 is due today or tomorrow by 9am in my mail box (4 th floor NSH) How are the machines working out? I have a meeting with Peter Lee and Bob
More informationRay Optics. Lecture 23. Chapter 34. Physics II. Course website:
Lecture 23 Chapter 34 Physics II Ray Optics Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Today we are going to discuss: Chapter 34: Section 34.1-3 Ray Optics Ray Optics Wave
More informationRay Optics. Lecture 23. Chapter 23. Physics II. Course website:
Lecture 23 Chapter 23 Physics II Ray Optics Course website: http://faculty.uml.edu/andriy_danylov/teaching/physicsii Let s finish talking about a diffraction grating Diffraction Grating Let s improve (more
More informationRefraction of Light. c = m / s. n = c v. The index of refraction is never less than 1. Some common indices of refraction are listed below.
Refraction of Light The speed of light in a vacuum is c = 3.00 10 8 m / s In air, the speed is only slightly less. In other transparent materials, such as glass and water, the speed is always less than
More informationLight and the Properties of Reflection & Refraction
Light and the Properties of Reflection & Refraction OBJECTIVE To study the imaging properties of a plane mirror. To prove the law of reflection from the previous imaging study. To study the refraction
More informationRendering: Reality. Eye acts as pinhole camera. Photons from light hit objects
Basic Ray Tracing Rendering: Reality Eye acts as pinhole camera Photons from light hit objects Rendering: Reality Eye acts as pinhole camera Photons from light hit objects Rendering: Reality Eye acts as
More informationLECTURE 25 Spherical Refracting Surfaces. Geometric Optics
LECTURE 25 Spherical Refracting Surfaces Geometric ptics When length scales are >> than the light s wavelength, light propagates as rays incident ray reflected ray θ θ r θ 2 refracted ray Reflection: Refraction:
More informationChapter 3. Physical phenomena: plane parallel plate. This chapter provides an explanation about how rays of light physically behave when
Chapter 3 Physical phenomena: plane parallel plate This chapter provides an explanation about how rays of light physically behave when propagating through different medium (different index of refraction).
More informationChapter 32 Light: Reflection and Refraction. Copyright 2009 Pearson Education, Inc.
Chapter 32 Light: Reflection and Refraction Units of Chapter 32 The Ray Model of Light Reflection; Image Formation by a Plane Mirror Formation of Images by Spherical Mirrors Index of Refraction Refraction:
More informationOptics INTRODUCTION DISCUSSION OF PRINCIPLES. Reflection by a Plane Mirror
Optics INTRODUCTION Geometric optics is one of the oldest branches of physics, dealing with the laws of reflection and refraction. Reflection takes place on the surface of an object, and refraction occurs
More informationSESSION 5: INVESTIGATING LIGHT. Key Concepts. X-planation. Physical Sciences Grade In this session we:
SESSION 5: INVESTIGATING LIGHT Key Concepts In this session we: Explain what light is, where light comes from and why it is important Identify what happens when light strikes the surface of different objects
More informationRay Tracing. Kjetil Babington
Ray Tracing Kjetil Babington 21.10.2011 1 Introduction What is Ray Tracing? Act of tracing a ray through some scene Not necessarily for rendering Rendering with Ray Tracing Ray Tracing is a global illumination
More informationComputer Graphics. Lecture 9 Environment mapping, Mirroring
Computer Graphics Lecture 9 Environment mapping, Mirroring Today Environment Mapping Introduction Cubic mapping Sphere mapping refractive mapping Mirroring Introduction reflection first stencil buffer
More informationLighting and Reflectance COS 426
ighting and Reflectance COS 426 Ray Casting R2mage *RayCast(R3Scene *scene, int width, int height) { R2mage *image = new R2mage(width, height); for (int i = 0; i < width; i++) { for (int j = 0; j < height;
More informationWavefronts and Rays. When light or other electromagnetic waves interact with systems much larger than the wavelength, it s a good approximation to
Chapter 33: Optics Wavefronts and Rays When light or other electromagnetic waves interact with systems much larger than the wavelength, it s a good approximation to Neglect the wave nature of light. Consider
More informationWhen light strikes an object there are different ways it can be affected. Light can be
When light strikes an object there are different ways it can be affected. Light can be transmitted, reflected, refracted, and absorbed, It depends on the type of matter that it strikes. For example light
More informationLight: Geometric Optics (Chapter 23)
Light: Geometric Optics (Chapter 23) Units of Chapter 23 The Ray Model of Light Reflection; Image Formed by a Plane Mirror Formation of Images by Spherical Index of Refraction Refraction: Snell s Law 1
More informationCS 6620 Shading. Steve Parker Peter Shirley
CS 6620 Shading Steve Parker Peter Shirley Shading models Lambert s cosine law Light reaching surface is proportional to projected area: cos θ Lambertian shading Comes from a rough surface (at microscopic
More informationP H Y L A B 1 : G E O M E T R I C O P T I C S
P H Y 1 4 3 L A B 1 : G E O M E T R I C O P T I C S Introduction Optics is the study of the way light interacts with other objects. This behavior can be extremely complicated. However, if the objects in
More informationLab 10 - GEOMETRICAL OPTICS
L10-1 Name Date Partners OBJECTIVES OVERVIEW Lab 10 - GEOMETRICAL OPTICS To examine Snell s Law. To observe total internal reflection. To understand and use the lens equations. To find the focal length
More informationPhysics 1C. Lecture 22A. "There are two ways of spreading light: to be the candle or the mirror that reflects it." --Edith Wharton
Physics 1C Lecture 22A "There are two ways of spreading light: to be the candle or the mirror that reflects it." --Edith Wharton The Nature of Light An interesting question developed as to the nature of
More informationCS5620 Intro to Computer Graphics
So Far wireframe hidden surfaces Next step 1 2 Light! Need to understand: How lighting works Types of lights Types of surfaces How shading works Shading algorithms What s Missing? Lighting vs. Shading
More informationspeed of light in vacuum = speed of light in the material
Chapter 5 Let Us Entertain You Snell s law states that as light enters a substance such as acrylic (high index of refraction) from air (low index of refraction), the light bends toward the normal. When
More informationØ Sampling Theory" Ø Fourier Analysis Ø Anti-aliasing Ø Supersampling Strategies" Ø The Hall illumination model. Ø Original ray tracing paper
CS 431/636 Advanced Rendering Techniques Ø Dr. David Breen Ø Korman 105D Ø Wednesday 6PM 8:50PM Presentation 6 5/16/12 Questions from ast Time? Ø Sampling Theory" Ø Fourier Analysis Ø Anti-aliasing Ø Supersampling
More informationPhysics 102: Lecture 17 Reflection and Refraction of Light
Physics 102: Lecture 17 Reflection and Refraction of Light Physics 102: Lecture 17, Slide 1 Today Last Time Recall from last time. Reflection: q i = q r Flat Mirror: image equidistant behind Spherical
More informationCS354 Computer Graphics Ray Tracing. Qixing Huang Januray 24th 2017
CS354 Computer Graphics Ray Tracing Qixing Huang Januray 24th 2017 Graphics Pipeline Elements of rendering Object Light Material Camera Geometric optics Modern theories of light treat it as both a wave
More informationLight and Lenses Notes
Light and Lenses Notes Refraction The change in speed and direction of a wave Due to change in medium Must cross boundary at an angle other than 90 o, otherwise no change in direction I R (unlike reflection)
More informationL. R. & S. M. VISSANJI ACADEMY SECONDARY SECTION PHYSICS - GRADE: VIII REFRACTION OF LIGHT
L. R. & S. M. VISSANJI ACADEMY SECONDARY SECTION - 2016-17 PHYSICS - GRADE: VIII REFRACTION OF LIGHT REFRACTION When light travels from one transparent medium to another transparent medium, it bends from
More informationLighting and Shading Computer Graphics I Lecture 7. Light Sources Phong Illumination Model Normal Vectors [Angel, Ch
15-462 Computer Graphics I Lecture 7 Lighting and Shading February 12, 2002 Frank Pfenning Carnegie Mellon University http://www.cs.cmu.edu/~fp/courses/graphics/ Light Sources Phong Illumination Model
More informationCOMP 175 COMPUTER GRAPHICS. Lecture 11: Recursive Ray Tracer. COMP 175: Computer Graphics April 9, Erik Anderson 11 Recursive Ray Tracer
Lecture 11: Recursive Ray Tracer COMP 175: Computer Graphics April 9, 2018 1/40 Note on using Libraries } C++ STL } Does not always have the same performance. } Interface is (mostly) the same, but implementations
More informationLighting affects appearance
Lighting affects appearance 1 Source emits photons Light And then some reach the eye/camera. Photons travel in a straight line When they hit an object they: bounce off in a new direction or are absorbed
More informationRay Tracing. CS334 Fall Daniel G. Aliaga Department of Computer Science Purdue University
Ray Tracing CS334 Fall 2013 Daniel G. Aliaga Department of Computer Science Purdue University Ray Casting and Ray Tracing Ray Casting Arthur Appel, started around 1968 Ray Tracing Turner Whitted, started
More informationUnit 9 Light & Optics
Unit 9 Light & Optics 1 A quick review of the properties of light. Light is a form of electromagnetic radiation Light travels as transverse waves having wavelength and frequency. fλ=c The velocity of EMR
More informationHomework Set 3 Due Thursday, 07/14
Homework Set 3 Due Thursday, 07/14 Problem 1 A room contains two parallel wall mirrors, on opposite walls 5 meters apart. The mirrors are 8 meters long. Suppose that one person stands in a doorway, in
More informationLight: Geometric Optics
Light: Geometric Optics The Ray Model of Light Light very often travels in straight lines. We represent light using rays, which are straight lines emanating from an object. This is an idealization, but
More informationPhysics Experiment 13
Fig. 13-1 Equipment This side of the mirror is gray. Place this side on the baseline. You can see your reflection on this side of the mirror. Fig. 13-2 Mirror Placement: The "Plexi-Ray Kit" contains a
More informationChapter 5 Mirror and Lenses
Chapter 5 Mirror and Lenses Name: 5.1 Ray Model of Light Another model for light is that it is made up of tiny particles called. Photons travel in perfect, lines from a light source This model helps us
More informationExperiment 9. Law of reflection and refraction of light
Experiment 9. Law of reflection and refraction of light 1. Purpose Invest light passing through two mediums boundary surface in order to understand reflection and refraction of light 2. Principle As shown
More informationFLAP P6.2 Rays and geometrical optics COPYRIGHT 1998 THE OPEN UNIVERSITY S570 V1.1
F1 The ray approximation in optics assumes that light travels from one point to another along a narrow path called a ray that may be represented by a directed line (i.e. a line with an arrow on it). In
More informationLight. Form of Electromagnetic Energy Only part of Electromagnetic Spectrum that we can really see
Light Form of Electromagnetic Energy Only part of Electromagnetic Spectrum that we can really see Facts About Light The speed of light, c, is constant in a vacuum. Light can be: REFLECTED ABSORBED REFRACTED
More informationGEOMETRIC OPTICS. LENSES refract light, so we need to know how light bends when entering and exiting a lens and how that interaction forms an image.
I. What is GEOMTERIC OPTICS GEOMETRIC OPTICS In geometric optics, LIGHT is treated as imaginary rays. How these rays interact with at the interface of different media, including lenses and mirrors, is
More informationRay Tracing. CS116B Chris Pollett Apr 20, 2004.
Ray Tracing CS116B Chris Pollett Apr 20, 2004. Outline Basic Ray-Tracing Intersections Basic Ray-Tracing Reference Point (i,j) Projection Plane Have a set up like in the above picture. Shoot rays from
More informationIntroduction to Visualization and Computer Graphics
Introduction to Visualization and Computer Graphics DH2320, Fall 2015 Prof. Dr. Tino Weinkauf Introduction to Visualization and Computer Graphics Visibility Shading 3D Rendering Geometric Model Color Perspective
More informationThe Question. What are the 4 types of interactions that waves can have when they encounter an object?
The Question What are the 4 types of interactions that waves can have when they encounter an object? Waves, Wave fronts and Rays Wave Front: Crests of the waves. Rays: Lines that are perpendicular to the
More information