# Pipeline Operations. CS 4620 Lecture 10

Size: px
Start display at page:

Transcription

1 Pipeline Operations CS 4620 Lecture Steve Marschner 1

2 Hidden surface elimination Goal is to figure out which color to make the pixels based on what s in front of what.

3 Hidden surface elimination We have discussed how to map primitives to image space projection and perspective are depth cues occlusion is another very important cue 2008 Steve Marschner 3

4 Back face culling For closed shapes you will never see the inside therefore only draw surfaces that face the camera implement by checking n. v n n v v 2008 Steve Marschner 4

5 5

6 Painter s algorithm Simplest way to do hidden surfaces Draw from back to front, use overwriting in framebuffer 2008 Steve Marschner 6

7 Painter s algorithm Amounts to a topological sort of the graph of occlusions that is, an edge from A to B means A sometimes occludes B any sort is valid D A D ABCDEF E B BADCFE A F C B E if there are cycles F there is no sort C 2008 Steve Marschner 7

8 Painter's algorithm examples of cycles No sort unless polygons are divided into small pieces 8

9 Painter s algorithm [Foley et al.] Useful when a valid order is easy to come by Compatible with alpha blending (later) 2008 Steve Marschner 9

10 The z buffer In many (most) applications maintaining a z sort is too expensive changes all the time when the view changes many data structures exist, but complex Solution: draw in any order, keep track of closest Z-buffer keeps track of closest depth so far when drawing, compare object s depth to current closest depth and discard if greater 2008 Steve Marschner 1

11 1

12 Z-Buffering: Algorithm allocate z-buffer; viewport. // Allocate depth buffer Same size as for each pixel (x,y) // For each pixel in viewport. writepixel(x,y,backgrnd); // Initialize color. writedepth(x,y,farplane); // Initialize depth (z) buffer. for each polygon // Draw each polygon (in any order). for each pixel (x,y) in polygon // Rasterize polygon. pz = polygon s z-value at (x,y);// Interpolate z-value at (x, y). if (pz > z-buffer(x,y)) // If new depth is closer: writepixel(x,y,color); // Write new (polygon) color. writedepth(x,y,pz); // Write new depth.

13 Z-Buffering: Example Scan convert the following two polygons. The number in the pixel represents the z- value for that pixel (0,3) (0,0) (3,0) (0,0) Does order matter? (3,0) (3,3)

14 Z-Buffering: Example = = = =

15 [Foley et al.] The z buffer another example of a memory-intensive brute force approach that works and has become the standard 2008 Steve Marschner 1

16 Z-Buffering : Summary Advantages: Easy to implement Fast with hardware support Fast depth buffer memory On most hardware No sorting of objects Shadows are easy (later) Disadvantages: Extra memory required for z-buffer: Integer depth values Scan-line algorithm Prone to aliasing Super-sampling

17 Pipeline for basic z buffer Vertex stage (input: position / vtx; color / tri) transform position (object to screen space) pass through color Rasterizer interpolated parameter: z (screen z) pass through color Fragment stage (output: color, z ) write to color planes only if interpolated z < current z 2008 Steve Marschner 1

18 Precision in z buffer The precision is distributed between the near and far clipping planes this is why these planes have to exist also why you can t always just set them to very small and very large distances Generally use z (not world z) in z buffer 2008 Steve Marschner 1

19 Interpolating in projection linear interp. in screen space linear interp. in world (eye) space Solution: linearly interpolate 1/z' Read, if you are interested, Steve Marschner 1

20 Flat shading Shade using the real normal of the triangle same result as ray tracing a bunch of triangles Leads to constant shading and faceted appearance [Foley et al.] truest view of the mesh geometry 2008 Steve Marschner 2

21 Pipeline for flat shading Vertex stage (input: position / vtx; color and normal / tri) transform position and normal (object to eye space) compute shaded color per triangle using normal transform position (eye to screen space) Rasterizer interpolated parameters: z (screen z) pass through color Fragment stage (output: color, z ) write to color planes only if interpolated z < current z 2008 Steve Marschner 2

22 Result of flat-shading pipeline 2008 Steve Marschner 2

23 Local vs. infinite viewer, light Phong illumination requires geometric information: light vector (function of position) eye vector (function of position) surface normal (from application) Light and eye vectors change need to be computed (and normalized) for each face 2008 Steve Marschner 2

24 Local vs. infinite viewer, light Look at case when eye or light is far away: distant light source: nearly parallel illumination distant eye point: nearly orthographic projection in both cases, eye or light vector changes very little Optimization: approximate eye and/or light as infinitely far away 2008 Steve Marschner 2

25 Directional light Directional (infinitely distant) light source light vector always points in the same direction often specified by position [x y z 0] many pipelines are faster if you use directional lights 2008 Steve Marschner 2

26 Infinite viewer Orthographic camera projection direction is constant Infinite viewer even with perspective, can approximate eye vector using the image plane normal can produce weirdness for wide-angle views Blinn-Phong: light, eye, half vectors all constant! 2008 Steve Marschner 2

27 Specular shading (Blinn-Phong) Close to mirror half vector near normal Measure near by dot product of unit vectors Cornell CS4620 Fall 2008 Lecture 3 specularly reflected light specular coefficient 2008 Steve Marschner 27

28 Gouraud shading [Gouraud thesis] Often we re trying to draw smooth surfaces, so facets are an artifact compute colors at vertices using vertex normals interpolate colors across triangles Gouraud shading Smooth shading 2008 Steve Marschner 2 ]

29 Pipeline for Gouraud shading Vertex stage (input: position, color, and normal / vtx) transform position and normal (object to eye space) compute shaded color per vertex transform position (eye to screen space) Rasterizer interpolated parameters: z (screen z); r, g, b color Fragment stage (output: color, z ) write to color planes only if interpolated z < current z 2008 Steve Marschner 2

30 Result of Gouraud shading pipeline 2008 Steve Marschner 3

31 Vertex normals e. g. spheres example Otherwise have to infer vtx. normals from triangles simple scheme: average surrounding face normals [Foley et al.] Need normals at vertices to compute Gouraud shading Best to get vtx. normals from the underlying geometry 2008 Steve Marschner 3

32 Non-diffuse Gouraud shading Can apply Gouraud shading to any illumination model it s just an interpolation method Results are not so good with fast-varying models like specular ones [Foley et al.] problems with any highlights smaller than a triangle 2008 Steve Marschner 3

33 Phong shading Get higher quality by interpolating the normal [Foley et al.] just as easy as interpolating the color but now we are evaluating the illumination model per pixel rather than per vertex (and normalizing the normal first) in pipeline, this means we are moving illumination from the vertex processing stage to the fragment processing stage 2008 Steve Marschner 3

34 Phong shading [Foley et al.] Bottom line: produces much better highlights 2008 Steve Marschner 3

35 Pipeline for Phong shading Vertex stage (input: position, color, and normal / vtx) transform position and normal (object to eye space) transform position (eye to screen space) pass through color Rasterizer interpolated parameters: z (screen z); r, g, b color; x, y, z normal Fragment stage (output: color, z ) compute shading using interpolated color and normal write to color planes only if interpolated z < current z 2008 Steve Marschner 3

36 Result of Phong shading pipeline 2008 Steve Marschner 3

### Pipeline Operations. CS 4620 Lecture 14

Pipeline Operations CS 4620 Lecture 14 2014 Steve Marschner 1 Pipeline you are here APPLICATION COMMAND STREAM 3D transformations; shading VERTEX PROCESSING TRANSFORMED GEOMETRY conversion of primitives

### Pipeline Operations. CS 4620 Lecture Steve Marschner. Cornell CS4620 Spring 2018 Lecture 11

Pipeline Operations CS 4620 Lecture 11 1 Pipeline you are here APPLICATION COMMAND STREAM 3D transformations; shading VERTEX PROCESSING TRANSFORMED GEOMETRY conversion of primitives to pixels RASTERIZATION

### CS4620/5620: Lecture 14 Pipeline

CS4620/5620: Lecture 14 Pipeline 1 Rasterizing triangles Summary 1! evaluation of linear functions on pixel grid 2! functions defined by parameter values at vertices 3! using extra parameters to determine

### graphics pipeline computer graphics graphics pipeline 2009 fabio pellacini 1

graphics pipeline computer graphics graphics pipeline 2009 fabio pellacini 1 graphics pipeline sequence of operations to generate an image using object-order processing primitives processed one-at-a-time

### graphics pipeline computer graphics graphics pipeline 2009 fabio pellacini 1

graphics pipeline computer graphics graphics pipeline 2009 fabio pellacini 1 graphics pipeline sequence of operations to generate an image using object-order processing primitives processed one-at-a-time

### 3D Rasterization II COS 426

3D Rasterization II COS 426 3D Rendering Pipeline (for direct illumination) 3D Primitives Modeling Transformation Lighting Viewing Transformation Projection Transformation Clipping Viewport Transformation

### The Rasterization Pipeline

Lecture 5: The Rasterization Pipeline Computer Graphics and Imaging UC Berkeley CS184/284A, Spring 2016 What We ve Covered So Far z x y z x y (0, 0) (w, h) Position objects and the camera in the world

### Computer Graphics 1. Chapter 7 (June 17th, 2010, 2-4pm): Shading and rendering. LMU München Medieninformatik Andreas Butz Computergraphik 1 SS2010

Computer Graphics 1 Chapter 7 (June 17th, 2010, 2-4pm): Shading and rendering 1 The 3D rendering pipeline (our version for this class) 3D models in model coordinates 3D models in world coordinates 2D Polygons

### Introduction 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

### Rasterization Overview

Rendering Overview The process of generating an image given a virtual camera objects light sources Various techniques rasterization (topic of this course) raytracing (topic of the course Advanced Computer

### CS 498 VR. Lecture 18-4/4/18. go.illinois.edu/vrlect18

CS 498 VR Lecture 18-4/4/18 go.illinois.edu/vrlect18 Review and Supplement for last lecture 1. What is aliasing? What is Screen Door Effect? 2. How image-order rendering works? 3. If there are several

### Rendering. Converting a 3D scene to a 2D image. Camera. Light. Rendering. View Plane

Rendering Pipeline Rendering Converting a 3D scene to a 2D image Rendering Light Camera 3D Model View Plane Rendering Converting a 3D scene to a 2D image Basic rendering tasks: Modeling: creating the world

### CS 464 Review. Review of Computer Graphics for Final Exam

CS 464 Review Review of Computer Graphics for Final Exam Goal: Draw 3D Scenes on Display Device 3D Scene Abstract Model Framebuffer Matrix of Screen Pixels In Computer Graphics: If it looks right then

### CS 130 Final. Fall 2015

CS 130 Final Fall 2015 Name Student ID Signature You may not ask any questions during the test. If you believe that there is something wrong with a question, write down what you think the question is trying

### CEng 477 Introduction to Computer Graphics Fall 2007

Visible Surface Detection CEng 477 Introduction to Computer Graphics Fall 2007 Visible Surface Detection Visible surface detection or hidden surface removal. Realistic scenes: closer objects occludes the

### CS 381 Computer Graphics, Fall 2008 Midterm Exam Solutions. The Midterm Exam was given in class on Thursday, October 23, 2008.

CS 381 Computer Graphics, Fall 2008 Midterm Exam Solutions The Midterm Exam was given in class on Thursday, October 23, 2008. 1. [4 pts] Drawing Where? Your instructor says that objects should always be

### Reading. 18. Projections and Z-buffers. Required: Watt, Section , 6.3, 6.6 (esp. intro and subsections 1, 4, and 8 10), Further reading:

Reading Required: Watt, Section 5.2.2 5.2.4, 6.3, 6.6 (esp. intro and subsections 1, 4, and 8 10), Further reading: 18. Projections and Z-buffers Foley, et al, Chapter 5.6 and Chapter 6 David F. Rogers

### CHAPTER 1 Graphics Systems and Models 3

?????? 1 CHAPTER 1 Graphics Systems and Models 3 1.1 Applications of Computer Graphics 4 1.1.1 Display of Information............. 4 1.1.2 Design.................... 5 1.1.3 Simulation and Animation...........

Computergrafik Thomas Buchberger, Matthias Zwicker Universität Bern Herbst 2008 Today Introduction Local shading models Light sources strategies Compute interaction of light with surfaces Requires simulation

### ECS 175 COMPUTER GRAPHICS. Ken Joy.! Winter 2014

ECS 175 COMPUTER GRAPHICS Ken Joy Winter 2014 Shading To be able to model shading, we simplify Uniform Media no scattering of light Opaque Objects No Interreflection Point Light Sources RGB Color (eliminating

### Deferred Rendering Due: Wednesday November 15 at 10pm

CMSC 23700 Autumn 2017 Introduction to Computer Graphics Project 4 November 2, 2017 Deferred Rendering Due: Wednesday November 15 at 10pm 1 Summary This assignment uses the same application architecture

### Interpolation using scanline algorithm

Interpolation using scanline algorithm Idea: Exploit knowledge about already computed color values. Traverse projected triangle top-down using scanline. Compute start and end color value of each pixel

### CMSC427 Advanced shading getting global illumination by local methods. Credit: slides Prof. Zwicker

CMSC427 Advanced shading getting global illumination by local methods Credit: slides Prof. Zwicker Topics Shadows Environment maps Reflection mapping Irradiance environment maps Ambient occlusion Reflection

Last Time? The Traditional Graphics Pipeline Reading for Today A Practical Model for Subsurface Light Transport, Jensen, Marschner, Levoy, & Hanrahan, SIGGRAPH 2001 Participating Media Measuring BRDFs

### CS 4620 Program 3: Pipeline

CS 4620 Program 3: Pipeline out: Wednesday 14 October 2009 due: Friday 30 October 2009 1 Introduction In this assignment, you will implement several types of shading in a simple software graphics pipeline.

### OpenGl Pipeline. triangles, lines, points, images. Per-vertex ops. Primitive assembly. Texturing. Rasterization. Per-fragment ops.

OpenGl Pipeline Individual Vertices Transformed Vertices Commands Processor Per-vertex ops Primitive assembly triangles, lines, points, images Primitives Fragments Rasterization Texturing Per-fragment

### Computer Graphics Lecture 11

1 / 14 Computer Graphics Lecture 11 Dr. Marc Eduard Frîncu West University of Timisoara May 15th 2012 2 / 14 Outline 1 Introduction 2 Transparency 3 Reflection 4 Recap 3 / 14 Introduction light = local

### Illumination & Shading: Part 1

Illumination & Shading: Part 1 Light Sources Empirical Illumination Shading Local vs Global Illumination Lecture 10 Comp 236 Spring 2005 Computer Graphics Jargon: Illumination Models Illumination - the

### CS230 : Computer Graphics Lecture 4. Tamar Shinar Computer Science & Engineering UC Riverside

CS230 : Computer Graphics Lecture 4 Tamar Shinar Computer Science & Engineering UC Riverside Shadows Shadows for each pixel do compute viewing ray if ( ray hits an object with t in [0, inf] ) then compute

### Mach band effect. The Mach band effect increases the visual unpleasant representation of curved surface using flat shading.

Mach band effect The Mach band effect increases the visual unpleasant representation of curved surface using flat shading. A B 320322: Graphics and Visualization 456 Mach band effect The Mach band effect

### Graphics and Interaction Surface rendering and shading

433-324 Graphics and Interaction Surface rendering and shading Department of Computer Science and Software Engineering The Lecture outline Introduction Surface rendering and shading Gouraud shading Phong

### Lecture outline Graphics and Interaction Surface rendering and shading. Shading techniques. Introduction. Surface rendering and shading

Lecture outline 433-324 Graphics and Interaction Surface rendering and shading Department of Computer Science and Software Engineering The Introduction Surface rendering and shading Gouraud shading Phong

### CS5620 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

### Graphics for VEs. Ruth Aylett

Graphics for VEs Ruth Aylett Overview VE Software Graphics for VEs The graphics pipeline Projections Lighting Shading VR software Two main types of software used: off-line authoring or modelling packages

Last Time? The Traditional Graphics Pipeline Participating Media Measuring BRDFs 3D Digitizing & Scattering BSSRDFs Monte Carlo Simulation Dipole Approximation Today Ray Casting / Tracing Advantages? Ray

### Surface Graphics. 200 polys 1,000 polys 15,000 polys. an empty foot. - a mesh of spline patches:

Surface Graphics Objects are explicitely defined by a surface or boundary representation (explicit inside vs outside) This boundary representation can be given by: - a mesh of polygons: 200 polys 1,000

### Computer Graphics I Lecture 11

15-462 Computer Graphics I Lecture 11 Midterm Review Assignment 3 Movie Midterm Review Midterm Preview February 26, 2002 Frank Pfenning Carnegie Mellon University http://www.cs.cmu.edu/~fp/courses/graphics/

### Models and Architectures. Ed Angel Professor of Computer Science, Electrical and Computer Engineering, and Media Arts University of New Mexico

Models and Architectures Ed Angel Professor of Computer Science, Electrical and Computer Engineering, and Media Arts University of New Mexico 1 Objectives Learn the basic design of a graphics system Introduce

### Blue colour text questions Black colour text sample answers Red colour text further explanation or references for the sample answers

Blue colour text questions Black colour text sample answers Red colour text further explanation or references for the sample answers Question 1. a) (5 marks) Explain the OpenGL synthetic camera model,

Final Projects Proposals due Thursday 4/8 Proposed project summary At least 3 related papers (read & summarized) Description of series of test cases Timeline & initial task assignment The Traditional Graphics

Computergrafik Matthias Zwicker Universität Bern Herbst 2009 Today Introduction Local shading models Light sources strategies Compute interaction of light with surfaces Requires simulation of physics Global

### CSE 690: GPGPU. Lecture 2: Understanding the Fabric - Intro to Graphics. Klaus Mueller Stony Brook University Computer Science Department

CSE 690: GPGPU Lecture 2: Understanding the Fabric - Intro to Graphics Klaus Mueller Stony Brook University Computer Science Department Klaus Mueller, Stony Brook 2005 1 Surface Graphics Objects are explicitely

### Graphics Hardware and Display Devices

Graphics Hardware and Display Devices CSE328 Lectures Graphics/Visualization Hardware Many graphics/visualization algorithms can be implemented efficiently and inexpensively in hardware Facilitates interactive

### Hidden surface removal. Computer Graphics

Lecture Hidden Surface Removal and Rasterization Taku Komura Hidden surface removal Drawing polygonal faces on screen consumes CPU cycles Illumination We cannot see every surface in scene We don t want

### Chapter 2 A top-down approach - How to make shaded images?

Chapter 2 A top-down approach - How to make shaded images? Comp. Graphics (U), Chap 2 Global View 1 CGGM Lab., CS Dept., NCTU Jung Hong Chuang Graphics API vs. application API Graphics API Support rendering

### Graphics and Interaction Rendering pipeline & object modelling

433-324 Graphics and Interaction Rendering pipeline & object modelling Department of Computer Science and Software Engineering The Lecture outline Introduction to Modelling Polygonal geometry The rendering

### https://ilearn.marist.edu/xsl-portal/tool/d4e4fd3a-a3...

Assessment Preview - This is an example student view of this assessment done Exam 2 Part 1 of 5 - Modern Graphics Pipeline Question 1 of 27 Match each stage in the graphics pipeline with a description

Illumination and Shading Illumination (Lighting)! Model the interaction of light with surface points to determine their final color and brightness! The illumination can be computed either at vertices or

### Computer Graphics. Bing-Yu Chen National Taiwan University The University of Tokyo

Computer Graphics Bing-Yu Chen National Taiwan University The University of Tokyo Hidden-Surface Removal Back-Face Culling The Depth-Sort Algorithm Binary Space-Partitioning Trees The z-buffer Algorithm

### Lets assume each object has a defined colour. Hence our illumination model is looks unrealistic.

Shading Models There are two main types of rendering that we cover, polygon rendering ray tracing Polygon rendering is used to apply illumination models to polygons, whereas ray tracing applies to arbitrary

### Introduction Rasterization Z-buffering Shading. Graphics 2012/2013, 4th quarter. Lecture 09: graphics pipeline (rasterization and shading)

Lecture 9 Graphics pipeline (rasterization and shading) Graphics pipeline - part 1 (recap) Perspective projection by matrix multiplication: x pixel y pixel z canonical 1 x = M vpm per M cam y z 1 This

### Graphics Pipeline 2D Geometric Transformations

Graphics Pipeline 2D Geometric Transformations CS 4620 Lecture 8 1 Plane projection in drawing Albrecht Dürer 2 Plane projection in drawing source unknown 3 Rasterizing triangles Summary 1 evaluation of

### CS 130 Exam I. Fall 2015

S 3 Exam I Fall 25 Name Student ID Signature You may not ask any questions during the test. If you believe that there is something wrong with a question, write down what you think the question is trying

### Hidden Surface Removal

Outline Introduction Hidden Surface Removal Hidden Surface Removal Simone Gasparini gasparini@elet.polimi.it Back face culling Depth sort Z-buffer Introduction Graphics pipeline Introduction Modeling Geom

### Introduction to Computer Graphics with WebGL

Introduction to Computer Graphics with WebGL Ed Angel Professor Emeritus of Computer Science Founding Director, Arts, Research, Technology and Science Laboratory University of New Mexico Models and Architectures

Illumination and Shading Computer Graphics COMP 770 (236) Spring 2007 Instructor: Brandon Lloyd 2/14/07 1 From last time Texture mapping overview notation wrapping Perspective-correct interpolation Texture

### CS Computer Graphics: Hidden Surface Removal

CS 543 - Computer Graphics: Hidden Surface Removal by Robert W. Lindeman gogo@wpi.edu (with help from Emmanuel Agu ;-) Hidden Surface Removal Drawing polygonal faces on screen consumes CPU cycles We cannot

9. Illumination and Shading Approaches for visual realism: - Remove hidden surfaces - Shade visible surfaces and reproduce shadows - Reproduce surface properties Texture Degree of transparency Roughness,

### Problem 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

### Graphics for VEs. Ruth Aylett

Graphics for VEs Ruth Aylett Overview VE Software Graphics for VEs The graphics pipeline Projections Lighting Shading Runtime VR systems Two major parts: initialisation and update loop. Initialisation

### - Rasterization. Geometry. Scan Conversion. Rasterization

Computer Graphics - The graphics pipeline - Geometry Modelview Geometry Processing Lighting Perspective Clipping Scan Conversion Texturing Fragment Tests Blending Framebuffer Fragment Processing - So far,

### CS 4620 Midterm, March 21, 2017

CS 460 Midterm, March 1, 017 This 90-minute exam has 4 questions worth a total of 100 points. Use the back of the pages if you need more space. Academic Integrity is expected of all students of Cornell

### Computer Graphics. Bing-Yu Chen National Taiwan University

Computer Graphics Bing-Yu Chen National Taiwan University Visible-Surface Determination Back-Face Culling The Depth-Sort Algorithm Binary Space-Partitioning Trees The z-buffer Algorithm Scan-Line Algorithm

### QUESTION BANK 10CS65 : COMPUTER GRAPHICS AND VISUALIZATION

QUESTION BANK 10CS65 : COMPUTER GRAPHICS AND VISUALIZATION INTRODUCTION OBJECTIVE: This chapter deals the applications of computer graphics and overview of graphics systems and imaging. UNIT I 1 With clear

### Level of Details in Computer Rendering

Level of Details in Computer Rendering Ariel Shamir Overview 1. Photo realism vs. Non photo realism (NPR) 2. Objects representations 3. Level of details Photo Realism Vs. Non Pixar Demonstrations Sketching,

### RASTERISED RENDERING

DH2323 DGI16 INTRODUCTION TO COMPUTER GRAPHICS AND INTERACTION RASTERISED RENDERING Christopher Peters HPCViz, KTH Royal Institute of Technology, Sweden chpeters@kth.se http://kth.academia.edu/christopheredwardpeters

### CS 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

### Projections and Hardware Rendering. Brian Curless CSE 557 Fall 2014

Projections and Hardware Rendering Brian Curless CSE 557 Fall 2014 1 Reading Required: Shirley, Ch. 7, Sec. 8.2, Ch. 18 Further reading: Foley, et al, Chapter 5.6 and Chapter 6 David F. Rogers and J. Alan

### VISIBILITY & CULLING. Don t draw what you can t see. Thomas Larsson, Afshin Ameri DVA338, Spring 2018, MDH

VISIBILITY & CULLING Don t draw what you can t see. Thomas Larsson, Afshin Ameri DVA338, Spring 2018, MDH Visibility Visibility Given a set of 3D objects, which surfaces are visible from a specific point

### Computer Graphics. Lecture 9 Hidden Surface Removal. Taku Komura

Computer Graphics Lecture 9 Hidden Surface Removal Taku Komura 1 Why Hidden Surface Removal? A correct rendering requires correct visibility calculations When multiple opaque polygons cover the same screen

Illumination Models & Shading Lighting vs. Shading Lighting Interaction between materials and light sources Physics Shading Determining the color of a pixel Computer Graphics ZBuffer(Scene) PutColor(x,y,Col(P));

### Lecture 17: Shading in OpenGL. CITS3003 Graphics & Animation

Lecture 17: Shading in OpenGL CITS3003 Graphics & Animation E. Angel and D. Shreiner: Interactive Computer Graphics 6E Addison-Wesley 2012 Objectives Introduce the OpenGL shading methods - per vertex shading

### Computer Graphics. Illumination and Shading

() Illumination and Shading Dr. Ayman Eldeib Lighting So given a 3-D triangle and a 3-D viewpoint, we can set the right pixels But what color should those pixels be? If we re attempting to create a realistic

### Computergrafik. Matthias Zwicker. Herbst 2010

Computergrafik Matthias Zwicker Universität Bern Herbst 2010 Today Bump mapping Shadows Shadow mapping Shadow mapping in OpenGL Bump mapping Surface detail is often the result of small perturbations in

### Computer Graphics Introduction. Taku Komura

Computer Graphics Introduction Taku Komura What s this course all about? We will cover Graphics programming and algorithms Graphics data structures Applied geometry, modeling and rendering Not covering

### Soft shadows. Steve Marschner Cornell University CS 569 Spring 2008, 21 February

Soft shadows Steve Marschner Cornell University CS 569 Spring 2008, 21 February Soft shadows are what we normally see in the real world. If you are near a bare halogen bulb, a stage spotlight, or other

### Homework #2. Shading, Ray Tracing, and Texture Mapping

Computer Graphics Prof. Brian Curless CSE 457 Spring 2000 Homework #2 Shading, Ray Tracing, and Texture Mapping Prepared by: Doug Johnson, Maya Widyasari, and Brian Curless Assigned: Monday, May 8, 2000

### Models and Architectures

Models and Architectures Objectives Learn the basic design of a graphics system Introduce graphics pipeline architecture Examine software components for an interactive graphics system 1 Image Formation

### Visualisatie BMT. Rendering. Arjan Kok

Visualisatie BMT Rendering Arjan Kok a.j.f.kok@tue.nl 1 Lecture overview Color Rendering Illumination 2 Visualization pipeline Raw Data Data Enrichment/Enhancement Derived Data Visualization Mapping Abstract

### Topics and things to know about them:

Practice Final CMSC 427 Distributed Tuesday, December 11, 2007 Review Session, Monday, December 17, 5:00pm, 4424 AV Williams Final: 10:30 AM Wednesday, December 19, 2007 General Guidelines: The final will

Complex Shading Algorithms CPSC 414 Overview So far Rendering Pipeline including recent developments Today Shading algorithms based on the Rendering Pipeline Arbitrary reflection models (BRDFs) Bump mapping

### Hidden Surfaces II. Week 9, Mon Mar 15

University of British Columbia CPSC 314 Computer Graphics Jan-Apr 2010 Tamara Munzner Hidden Surfaces II Week 9, Mon Mar 15 http://www.ugrad.cs.ubc.ca/~cs314/vjan2010 ews yes, I'm granting the request

### CS452/552; EE465/505. Intro to Lighting

CS452/552; EE465/505 Intro to Lighting 2-10 15 Outline! Projection Normalization! Introduction to Lighting (and Shading) Read: Angel Chapter 5., sections 5.4-5.7 Parallel Projections Chapter 6, sections

### Institutionen för systemteknik

Code: Day: Lokal: M7002E 19 March E1026 Institutionen för systemteknik Examination in: M7002E, Computer Graphics and Virtual Environments Number of sections: 7 Max. score: 100 (normally 60 is required

### Introduction to Computer Graphics 7. Shading

Introduction to Computer Graphics 7. Shading National Chiao Tung Univ, Taiwan By: I-Chen Lin, Assistant Professor Textbook: Hearn and Baker, Computer Graphics, 3rd Ed., Prentice Hall Ref: E.Angel, Interactive

### Rendering. Illumination Model. Wireframe rendering simple, ambiguous Color filling flat without any 3D information

llumination Model Wireframe rendering simple, ambiguous Color filling flat without any 3D information Requires modeling interaction of light with the object/surface to have a different color (shade in

### COMP environment mapping Mar. 12, r = 2n(n v) v

Rendering mirror surfaces The next texture mapping method assumes we have a mirror surface, or at least a reflectance function that contains a mirror component. Examples might be a car window or hood,

### CS 130 Exam I. Fall 2015

CS 130 Exam I Fall 2015 Name Student ID Signature You may not ask any questions during the test. If you believe that there is something wrong with a question, write down what you think the question is

### Texture. Texture Mapping. Texture Mapping. CS 475 / CS 675 Computer Graphics. Lecture 11 : Texture

Texture CS 475 / CS 675 Computer Graphics Add surface detail Paste a photograph over a surface to provide detail. Texture can change surface colour or modulate surface colour. Lecture 11 : Texture http://en.wikipedia.org/wiki/uv_mapping

### CSE 167: Introduction to Computer Graphics Lecture #7: Lights. Jürgen P. Schulze, Ph.D. University of California, San Diego Spring Quarter 2015

CSE 167: Introduction to Computer Graphics Lecture #7: Lights Jürgen P. Schulze, Ph.D. University of California, San Diego Spring Quarter 2015 Announcements Thursday in-class: Midterm Can include material

### Computer Graphics. Illumination and Shading

Rendering Pipeline modelling of geometry transformation into world coordinates placement of cameras and light sources transformation into camera coordinates backface culling projection clipping w.r.t.

### Virtual Reality for Human Computer Interaction

Virtual Reality for Human Computer Interaction Appearance: Lighting Representation of Light and Color Do we need to represent all I! to represent a color C(I)? No we can approximate using a three-color

### CS 475 / CS 675 Computer Graphics. Lecture 11 : Texture

CS 475 / CS 675 Computer Graphics Lecture 11 : Texture Texture Add surface detail Paste a photograph over a surface to provide detail. Texture can change surface colour or modulate surface colour. http://en.wikipedia.org/wiki/uv_mapping

### Intro to Ray-Tracing & Ray-Surface Acceleration

Lecture 12 & 13: Intro to Ray-Tracing & Ray-Surface Acceleration Computer Graphics and Imaging UC Berkeley Course Roadmap Rasterization Pipeline Core Concepts Sampling Antialiasing Transforms Geometric

Illumination and Shading Illumination and Shading z Illumination Models y Ambient y Diffuse y Attenuation y Specular Reflection z Interpolated Shading Models y Flat, Gouraud, Phong y Problems CS4451: Fall