Volume Illumination & Vector Field Visualisation
|
|
- Lindsay Charles
- 5 years ago
- Views:
Transcription
1 Volume Illumination & Vector Field Visualisation Visualisation Lecture 11 Institute for Perception, Action & Behaviour School of Informatics Volume Illumination & Vector Vis. 1
2 Previously : Volume Rendering Image Order Volume Rendering Object Order Volume Rendering ray casting / intensity transfer function splatting / hybrid shear-warp rendering algorithm Volume Classification volume scalars colour & opacity feature isolation & classification transparency & clipping Volume Illumination & Vector Vis. 2
3 Light Propagation in Volumes Lighting in volume only transmission and emission considered (until now) can also: reflect light scatter light into different directions Volume Illumination & Vector Vis. 3
4 Global Illumination of Volumes For every voxel ray intersects, need to consider: Light absorbed. Light emitted. Light scattered out of the ray. Light scattered into the ray. Volume Illumination & Vector Vis. 4
5 Global Illumination of Volumes For every voxel ray intersects, need to consider: Light absorbed. Normally ignore scattering in volumetric illumination Light!Light emitted. scattered out of the ray. Light scattered into the ray. Why? : computational cost Volume Illumination & Vector Vis. 5
6 Example: single scatter Synthetic images of the Earth s atmosphere produced by Rayleigh scattering. Irwin 95. Light scattered to produce atmospheric haze effect Volume Illumination & Vector Vis. 6
7 Example : multiple scattering Scattering has scale dependence can see this is quite a small cloud. Light scattered multiple times to produce simulation of a cloud Volume Illumination & Vector Vis. 7
8 Example : sub-surface scattering Very large statue Medium sized Small statue. Varying how light is scattered inside a surface affects perception hence useful in visualisation why? - prior visual experience, perception of distance? Volume Illumination & Vector Vis. 8
9 Volume Illumination -? Anyway, scattering is to costly so we usually do not take them into account when doing volume rendering But we still can add slight shadows to the volume by illuminating them Volume Illumination & Vector Vis. 9
10 Volume Illumination Why do we want to illuminate volumes? illumination helps us to better understand 3D structure displays visual cues to surface orientation highlight significant gradients within volume Volume Illumination & Vector Vis. 10
11 What are we illuminating? embedded (iso-) surface sharp gradients in opacity Volume Illumination & Vector Vis. 11
12 Shading an Embedded isosurface classify volume with a step function use regular specular / diffuse surface shading Remember for lighting equations of lecture 2 require illumination direction camera model (position) surface orientation need to calculate and store surface normal (for our voxel in order to illuminate them) Volume Illumination & Vector Vis. 12
13 Estimating the surface normal from distance map Use distance map to the iso-surface value 1. Determine the threshold value 2. Determine the surface voxels based on the threshold 3. Compute the normal vectors based on centred difference method 1 zthe x = z x 1, y z x 1, y For example, if we sample 2 centre of the voxels, 1 z y = z x, y 1 z x, y 1 2 z x z y 1 N = 2, 2, z x z y 1 z x z y 1 z x z y 1 Volume Illumination & Vector Vis. 13
14 Result : illuminated iso-surface MIP technique Surface normals recovered from depth map of surface Shaded embedded isosurface. regions of similar curvature taken into consideration Volume Illumination & Vector Vis. 14
15 Normals are sensitive to step size Step size through the volume / over the depth map Step = 2.0 Step = 1.0 Step = 0.1 Artefacts with larger step sizes under standard lighting model Volume Illumination & Vector Vis. 15
16 Illuminating Opacity (Scalar) Gradient Illuminate scalar gradient instead of iso-surface requirement : estimate and store gradient at every voxel Composite Shaded Composite Shaded opacity gradient (shades changes in opacity) Volume Illumination & Vector Vis. 16
17 Estimating Opacity Gradient Use 3D centred difference operator I = I x, I y, I z = I, I, I x y z I x 1, y, z I x 1, y, z I= x 2 We can extract the normal vectors of the region where the scalar values are changing significantly, i.e. boundary of tissues Evaluate at each voxel and interpolate Volume Illumination & Vector Vis. 17
18 Illumination : storing normal vectors Visualisation is interactive compute normal vectors for surface/gradient once store normal perform interactive shading calculations Storage : 2563 data set of 1-byte scalars ~16Mb normal vector (stored as floating point(4-byte)) ~ 200Mb! Solution : quantise direction & magnitude as small number of bits Volume Illumination & Vector Vis. 18
19 Illumination : storing normal vectors Quantize vector direction into one of N directions on a sub-divided sphere Subdivide an octahedron into a sphere. Number the vertices. Encode the direction according the nearest vertex that the vector passes through. For infinite light sources, only need to calculate the shading values once and store these in a table. Volume Illumination & Vector Vis. 19
20 Volume Illumination Summary Illumination can aid visual understanding of volumes scattering gives clue to object scale / effects perception too expensive at current time for interactive visualisation Illumination of: embedded isosurface gradient magnitude finite difference estimation Normal vector storage for each cell need to estimate surface normal use depth map use index into triangulated sphere Volume Illumination & Vector Vis. 20
21 Visualising Vectors Examples of vector data: meteorological analyses / simulation medical blood flow measurement Computational simulation of flow over aircraft, ships, submarines etc. visualisation of derivatives Why is visualising these difficult? not just of flow itself 2 or 3 components per data point, temporal aspects of vector flow, vector density Volume Illumination & Vector Vis. 21
22 Insight in Vector Fields Two properties of vector fields to visualise : local view of the flow global view of the flow e.g a meteorological wind forecast Local : for given location, what is the current wind strength and direction Global: a given location, where has the wind flow come from, and where will it go to. Volume Illumination & Vector Vis. 22
23 Two Methods of Flow Visualisation Visualise Flow wrt fixed point e.g. plot flow glyphs to show local direction and magnitude local view of vector field Visualise flow as the trajectory of a particles transported by the flow e.g plot particle traces, streamlines etc. global view of vector field require integrating the flow equation Volume Illumination & Vector Vis. 23
24 State of Flow : Steady / Unsteady Steady flow remains constant over time state of equilibrium or snapshot use particle traces known as streamlines Unsteady flow varies with time implications to tracing massless particles particle traces known as streaklines show little information about flow direction or magnitude Volume Illumination & Vector Vis. 24
25 Vectors : local visualisation Set of basic methods for showing local view: oriented lines, hedgehogs & glyphs colour mapping vector components warping animation Volume Illumination & Vector Vis. 25
26 Local vector visualisation : lines Draw line at data point indicating vector direction scale according to magnitude indicate direction as vector orientation problems non-uniform spacing showing large dynamic range field e.g. speed Option : use barbs to show speed Volume Illumination & Vector Vis. 26
27 Example : meteorology NOAA/FSL Lines are drawn with constant length, barbs indicate wind speed. Also colour mapped scalar field of wind speed. Volume Illumination & Vector Vis. 27
28 Example : lines in 3D Problems : Difficult to understand position and orientation in projection to 2D image. Clutter is also a problem. Volume Illumination & Vector Vis. 28
29 Local vector visualisation : colour map Dense Normal Vectors in 3D capture of large scale environment X component = Red. Y component = Green Z component = Blue. Returned laser power Distance to object (darker is closer black is no data) Volume Illumination & Vector Vis. 29
30 Local vector visualisation : Glyphs 2D or 3D objects inserted at data point, oriented with vector flow problem : scaling scaling glyph results in non-linear change in appearance surface area changes with square of size problem : clutter e.g. blood flow (reduced data) colourmap shows magnitude in addition to glyph scale Volume Illumination & Vector Vis. 30
31 Local vector visualisation : Warping deform geometry according to the vector field vector fields often associated with motion, or displacement. e.g vibration of a beam. Volume Illumination & Vector Vis. 31
32 Example : warping Insert slice planes into the data volume Displace surface according to flow momentum take care with scaling to avoid excessive geometric distortion surfaces may intersect, or even turn inside-out Volume Illumination & Vector Vis. 32
33 Local vector visualisation : animation Animation to enhance lines or glyphs improved clarity of magnitude and/or direction draw lines or glyphs & animate over time removes ambiguity in line or glyph direction also move glyphs along a streamline to visualise transport Volume Illumination & Vector Vis. 33
34 Vector Visualisation Summary Vector visualisation: local view / global view steady / unsteady flow methods of vector visualisation : Local Vector Visualisation: lines, hedgehogs & glyphs colour mapping, warping & animation Next lecture : more vector fields! Volume Illumination & Vector Vis. 34
Volume Illumination. Visualisation Lecture 11. Taku Komura. Institute for Perception, Action & Behaviour School of Informatics
Volume Illumination Visualisation Lecture 11 Taku Komura Institute for Perception, Action & Behaviour School of Informatics Taku Komura Volume Illumination & Vector Vis. 1 Previously : Volume Rendering
More informationVolume Illumination and Segmentation
Volume Illumination and Segmentation Computer Animation and Visualisation Lecture 13 Institute for Perception, Action & Behaviour School of Informatics Overview Volume illumination Segmentation Volume
More informationVolume Illumination, Contouring
Volume Illumination, Contouring Computer Animation and Visualisation Lecture 0 tkomura@inf.ed.ac.uk Institute for Perception, Action & Behaviour School of Informatics Contouring Scaler Data Overview -
More informationVector Field Visualisation
Vector Field Visualisation Computer Animation and Visualization Lecture 14 Institute for Perception, Action & Behaviour School of Informatics Visualising Vectors Examples of vector data: meteorological
More informationPreviously... contour or image rendering in 2D
Volume Rendering Visualisation Lecture 10 Taku Komura Institute for Perception, Action & Behaviour School of Informatics Volume Rendering 1 Previously... contour or image rendering in 2D 2D Contour line
More informationVolume Rendering. Computer Animation and Visualisation Lecture 9. Taku Komura. Institute for Perception, Action & Behaviour School of Informatics
Volume Rendering Computer Animation and Visualisation Lecture 9 Taku Komura Institute for Perception, Action & Behaviour School of Informatics Volume Rendering 1 Volume Data Usually, a data uniformly distributed
More information11/1/13. Visualization. Scientific Visualization. Types of Data. Height Field. Contour Curves. Meshes
CSCI 420 Computer Graphics Lecture 26 Visualization Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 2.11] Jernej Barbic University of Southern California Scientific Visualization
More informationVisualization. CSCI 420 Computer Graphics Lecture 26
CSCI 420 Computer Graphics Lecture 26 Visualization Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 11] Jernej Barbic University of Southern California 1 Scientific Visualization
More informationScalar Algorithms: Contouring
Scalar Algorithms: Contouring Computer Animation and Visualisation Lecture tkomura@inf.ed.ac.uk Institute for Perception, Action & Behaviour School of Informatics Contouring Scaler Data Last Lecture...
More informationData Visualization (DSC 530/CIS )
Data Visualization (DSC 530/CIS 60-0) Isosurfaces & Volume Rendering Dr. David Koop Fields & Grids Fields: - Values come from a continuous domain, infinitely many values - Sampled at certain positions
More informationVector Visualisation 1. global view
Vector Field Visualisation : global view Visualisation Lecture 12 Institute for Perception, Action & Behaviour School of Informatics Vector Visualisation 1 Vector Field Visualisation : local & global Vector
More informationData Visualization (CIS/DSC 468)
Data Visualization (CIS/DSC 468) Vector Visualization Dr. David Koop Visualizing Volume (3D) Data 2D visualization slice images (or multi-planar reformating MPR) Indirect 3D visualization isosurfaces (or
More informationCIS 467/602-01: Data Visualization
CIS 467/60-01: Data Visualization Isosurfacing and Volume Rendering Dr. David Koop Fields and Grids Fields: values come from a continuous domain, infinitely many values - Sampled at certain positions to
More informationVisualization Computer Graphics I Lecture 20
15-462 Computer Graphics I Lecture 20 Visualization Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 12] April 15, 2003 Frank Pfenning Carnegie Mellon University http://www.cs.cmu.edu/~fp/courses/graphics/
More informationHeight Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 12] April 23, 2002 Frank Pfenning Carnegie Mellon University
15-462 Computer Graphics I Lecture 21 Visualization Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 12] April 23, 2002 Frank Pfenning Carnegie Mellon University http://www.cs.cmu.edu/~fp/courses/graphics/
More informationLecture overview. Visualisatie BMT. Fundamental algorithms. Visualization pipeline. Structural classification - 1. Structural classification - 2
Visualisatie BMT Fundamental algorithms Arjan Kok a.j.f.kok@tue.nl Lecture overview Classification of algorithms Scalar algorithms Vector algorithms Tensor algorithms Modeling algorithms 1 2 Visualization
More informationVisualization. Images are used to aid in understanding of data. Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [chapter 26]
Visualization Images are used to aid in understanding of data Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [chapter 26] Tumor SCI, Utah Scientific Visualization Visualize large
More informationData Visualization (DSC 530/CIS )
Data Visualization (DSC 530/CIS 60-01) Scalar Visualization Dr. David Koop Online JavaScript Resources http://learnjsdata.com/ Good coverage of data wrangling using JavaScript Fields in Visualization Scalar
More informationVisualization Computer Graphics I Lecture 20
15-462 Computer Graphics I Lecture 20 Visualization Height Fields and Contours Scalar Fields Volume Rendering Vector Fields [Angel Ch. 12] November 20, 2003 Doug James Carnegie Mellon University http://www.cs.cmu.edu/~djames/15-462/fall03
More informationData Representation in Visualisation
Data Representation in Visualisation Visualisation Lecture 4 Taku Komura Institute for Perception, Action & Behaviour School of Informatics Taku Komura Data Representation 1 Data Representation We have
More informationVolume visualization. Volume visualization. Volume visualization methods. Sources of volume visualization. Sources of volume visualization
Volume visualization Volume visualization Volumes are special cases of scalar data: regular 3D grids of scalars, typically interpreted as density values. Each data value is assumed to describe a cubic
More informationData Visualization (CIS/DSC 468)
Data Visualization (CIS/DSC 46) Volume Rendering Dr. David Koop Visualizing Volume (3D) Data 2D visualization slice images (or multi-planar reformating MPR) Indirect 3D visualization isosurfaces (or surface-shaded
More informationFlow Visualisation 1
Flow Visualisation Visualisation Lecture 13 Institute for Perception, Action & Behaviour School of Informatics Flow Visualisation 1 Flow Visualisation... so far Vector Field Visualisation vector fields
More informationRaycasting. Ronald Peikert SciVis Raycasting 3-1
Raycasting Ronald Peikert SciVis 2007 - Raycasting 3-1 Direct volume rendering Volume rendering (sometimes called direct volume rendering) stands for methods that generate images directly from 3D scalar
More informationLecture overview. Visualisatie BMT. Transparency. Transparency. Transparency. Transparency. Transparency Volume rendering Assignment
Visualisatie BMT Lecture overview Assignment Arjan Kok a.j.f.kok@tue.nl 1 Makes it possible to see inside or behind objects Complement of transparency is opacity Opacity defined by alpha value with range
More informationOptical Models of Direct Volume Rendering by Nelson Max
Optical Models of Direct Volume Rendering by Nelson Max By Michael Shah Duration: 15~20minutes February 7, 2011 Slides and study guide available at http://www.cse.ohio-state.edu/ ~shahmi/coursework.html
More informationCIS 467/602-01: Data Visualization
CIS 467/602-01: Data Visualization Vector Field Visualization Dr. David Koop Fields Tables Networks & Trees Fields Geometry Clusters, Sets, Lists Items Items (nodes) Grids Items Items Attributes Links
More informationScalar Data. Visualization Torsten Möller. Weiskopf/Machiraju/Möller
Scalar Data Visualization Torsten Möller Weiskopf/Machiraju/Möller Overview Basic strategies Function plots and height fields Isolines Color coding Volume visualization (overview) Classification Segmentation
More informationlecture 21 volume rendering - blending N layers - OpenGL fog (not on final exam) - transfer functions - rendering level surfaces
lecture 21 volume rendering - blending N layers - OpenGL fog (not on final exam) - transfer functions - rendering level surfaces - 3D objects Clouds, fire, smoke, fog, and dust are difficult to model with
More informationLecture overview. Visualisatie BMT. Vector algorithms. Vector algorithms. Time animation. Time animation
Visualisatie BMT Lecture overview Vector algorithms Tensor algorithms Modeling algorithms Algorithms - 2 Arjan Kok a.j.f.kok@tue.nl 1 2 Vector algorithms Vector 2 or 3 dimensional representation of direction
More informationContours & Implicit Modelling 4
Brief Recap Contouring & Implicit Modelling Contouring Implicit Functions Visualisation Lecture 8 lecture 6 Marching Cubes lecture 3 visualisation of a Quadric toby.breckon@ed.ac.uk Computer Vision Lab.
More informationProcessing 3D Surface Data
Processing 3D Surface Data Computer Animation and Visualisation Lecture 15 Institute for Perception, Action & Behaviour School of Informatics 3D Surfaces 1 3D surface data... where from? Iso-surfacing
More informationDisplay. Introduction page 67 2D Images page 68. All Orientations page 69 Single Image page 70 3D Images page 71
Display Introduction page 67 2D Images page 68 All Orientations page 69 Single Image page 70 3D Images page 71 Intersecting Sections page 71 Cube Sections page 72 Render page 73 1. Tissue Maps page 77
More informationFundamental Algorithms
Fundamental Algorithms Fundamental Algorithms 3-1 Overview This chapter introduces some basic techniques for visualizing different types of scientific data sets. We will categorize visualization methods
More informationScientific Visualization. CSC 7443: Scientific Information Visualization
Scientific Visualization Scientific Datasets Gaining insight into scientific data by representing the data by computer graphics Scientific data sources Computation Real material simulation/modeling (e.g.,
More informationVisualizer An implicit surface rendering application
June 01, 2004 Visualizer An implicit surface rendering application Derek Gerstmann - C1405511 MSc Computer Animation NCCA Bournemouth University OVERVIEW OF APPLICATION Visualizer is an interactive application
More informationVolume Visualization
Volume Visualization Part 1 (out of 3) Overview: Volume Visualization Introduction to volume visualization On volume data Surface vs. volume rendering Overview: Techniques Simple methods Slicing, cuberille
More informationVirtual 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
More informationProcessing 3D Surface Data
Processing 3D Surface Data Computer Animation and Visualisation Lecture 17 Institute for Perception, Action & Behaviour School of Informatics 3D Surfaces 1 3D surface data... where from? Iso-surfacing
More informationProcessing 3D Surface Data
Processing 3D Surface Data Computer Animation and Visualisation Lecture 12 Institute for Perception, Action & Behaviour School of Informatics 3D Surfaces 1 3D surface data... where from? Iso-surfacing
More informationLecture 15: Shading-I. CITS3003 Graphics & Animation
Lecture 15: Shading-I CITS3003 Graphics & Animation E. Angel and D. Shreiner: Interactive Computer Graphics 6E Addison-Wesley 2012 Objectives Learn that with appropriate shading so objects appear as threedimensional
More informationVolume Visualization. Part 1 (out of 3) Volume Data. Where do the data come from? 3D Data Space How are volume data organized?
Volume Data Volume Visualization Part 1 (out of 3) Where do the data come from? Medical Application Computed Tomographie (CT) Magnetic Resonance Imaging (MR) Materials testing Industrial-CT Simulation
More informationFast Visualization of Object Contours by Non-Photorealistic Volume Rendering
Fast Visualization of Object Contours by Non-Photorealistic Volume Rendering Balázs Csébfalvi bfalvi,, Lukas Mroz, Helwig Hauser, Andreas König, Eduard Gröller Institute of Computer Graphics and Algorithms
More informationVolume Rendering - Introduction. Markus Hadwiger Visual Computing Center King Abdullah University of Science and Technology
Volume Rendering - Introduction Markus Hadwiger Visual Computing Center King Abdullah University of Science and Technology Volume Visualization 2D visualization: slice images (or multi-planar reformation:
More informationCPSC GLOBAL ILLUMINATION
CPSC 314 21 GLOBAL ILLUMINATION Textbook: 20 UGRAD.CS.UBC.CA/~CS314 Mikhail Bessmeltsev ILLUMINATION MODELS/ALGORITHMS Local illumination - Fast Ignore real physics, approximate the look Interaction of
More informationHardware Accelerated Volume Visualization. Leonid I. Dimitrov & Milos Sramek GMI Austrian Academy of Sciences
Hardware Accelerated Volume Visualization Leonid I. Dimitrov & Milos Sramek GMI Austrian Academy of Sciences A Real-Time VR System Real-Time: 25-30 frames per second 4D visualization: real time input of
More informationCOMPUTER GRAPHICS AND INTERACTION
DH2323 DGI17 COMPUTER GRAPHICS AND INTERACTION INTRODUCTION TO RAYTRACING Christopher Peters CST, KTH Royal Institute of Technology, Sweden chpeters@kth.se http://kth.academia.edu/christopheredwardpeters
More informationThe exam begins at 2:40pm and ends at 4:00pm. You must turn your exam in when time is announced or risk not having it accepted.
CS 184: Foundations of Computer Graphics page 1 of 12 Student Name: Student ID: Instructions: Read them carefully! The exam begins at 2:40pm and ends at 4:00pm. You must turn your exam in when time is
More informationGraphics 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
More informationScalar Data. CMPT 467/767 Visualization Torsten Möller. Weiskopf/Machiraju/Möller
Scalar Data CMPT 467/767 Visualization Torsten Möller Weiskopf/Machiraju/Möller Overview Basic strategies Function plots and height fields Isolines Color coding Volume visualization (overview) Classification
More informationComputer Graphics Ray Casting. Matthias Teschner
Computer Graphics Ray Casting Matthias Teschner Outline Context Implicit surfaces Parametric surfaces Combined objects Triangles Axis-aligned boxes Iso-surfaces in grids Summary University of Freiburg
More informationTopic 12: Texture Mapping. Motivation Sources of texture Texture coordinates Bump mapping, mip-mapping & env mapping
Topic 12: Texture Mapping Motivation Sources of texture Texture coordinates Bump mapping, mip-mapping & env mapping Texture sources: Photographs Texture sources: Procedural Texture sources: Solid textures
More informationCourse Review. Computer Animation and Visualisation. Taku Komura
Course Review Computer Animation and Visualisation Taku Komura Characters include Human models Virtual characters Animal models Representation of postures The body has a hierarchical structure Many types
More informationDirect Volume Rendering
Direct Volume Rendering Balázs Csébfalvi Department of Control Engineering and Information Technology Budapest University of Technology and Economics Classification of Visualization Algorithms Indirect
More informationVolume Rendering. Lecture 21
Volume Rendering Lecture 21 Acknowledgements These slides are collected from many sources. A particularly valuable source is the IEEE Visualization conference tutorials. Sources from: Roger Crawfis, Klaus
More informationContours & Implicit Modelling 1
Contouring & Implicit Modelling Visualisation Lecture 8 Institute for Perception, Action & Behaviour School of Informatics Contours & Implicit Modelling 1 Brief Recap Contouring Implicit Functions lecture
More information8. Tensor Field Visualization
8. Tensor Field Visualization Tensor: extension of concept of scalar and vector Tensor data for a tensor of level k is given by t i1,i2,,ik (x 1,,x n ) Second-order tensor often represented by matrix Examples:
More informationVisual cues to 3D geometry. Light Reflection and Advanced Shading. Shading. Recognizing materials. size (perspective) occlusion shading
Visual cues to 3D geometry Light Reflection and Advanced Shading size (perspective) occlusion shading CS 4620 Lecture 17 1 2 Shading Recognizing materials Variation in observed color across an object strongly
More informationVector Visualization
Vector Visualization Vector Visulization Divergence and Vorticity Vector Glyphs Vector Color Coding Displacement Plots Stream Objects Texture-Based Vector Visualization Simplified Representation of Vector
More informationScalar Visualization
Scalar Visualization Visualizing scalar data Popular scalar visualization techniques Color mapping Contouring Height plots outline Recap of Chap 4: Visualization Pipeline 1. Data Importing 2. Data Filtering
More informationFlow Visualization with Integral Surfaces
Flow Visualization with Integral Surfaces Visual and Interactive Computing Group Department of Computer Science Swansea University R.S.Laramee@swansea.ac.uk 1 1 Overview Flow Visualization with Integral
More informationGPU-based Volume Rendering. Michal Červeňanský
GPU-based Volume Rendering Michal Červeňanský Outline Volume Data Volume Rendering GPU rendering Classification Speed-up techniques Other techniques 2 Volume Data Describe interior structures Liquids,
More informationComputer Graphics and Visualization. What is computer graphics?
CSCI 120 Computer Graphics and Visualization Shiaofen Fang Department of Computer and Information Science Indiana University Purdue University Indianapolis What is computer graphics? Computer graphics
More informationIllumination and Shading
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
More informationComputer 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/
More informationInteractive Computer Graphics A TOP-DOWN APPROACH WITH SHADER-BASED OPENGL
International Edition Interactive Computer Graphics A TOP-DOWN APPROACH WITH SHADER-BASED OPENGL Sixth Edition Edward Angel Dave Shreiner Interactive Computer Graphics: A Top-Down Approach with Shader-Based
More informationTopic 11: Texture Mapping 11/13/2017. Texture sources: Solid textures. Texture sources: Synthesized
Topic 11: Texture Mapping Motivation Sources of texture Texture coordinates Bump mapping, mip mapping & env mapping Texture sources: Photographs Texture sources: Procedural Texture sources: Solid textures
More informationVisualization Toolkit(VTK) Atul Kumar MD MMST PhD IRCAD-Taiwan
Visualization Toolkit(VTK) Atul Kumar MD MMST PhD IRCAD-Taiwan Visualization What is visualization?: Informally, it is the transformation of data or information into pictures.(scientific, Data, Information)
More informationRAYTRACING. Christopher Peters INTRODUCTION TO COMPUTER GRAPHICS AND INTERACTION. HPCViz, KTH Royal Institute of Technology, Sweden
DH2323 DGI15 INTRODUCTION TO COMPUTER GRAPHICS AND INTERACTION RAYTRACING HPCViz, KTH Royal Institute of Technology, Sweden http://kth.academia.edu/christopheredwardpeters Based on DGI12 notes by Carl
More informationLecture 18: Primer on Ray Tracing Techniques
Lecture 18: Primer on Ray Tracing Techniques 6.172: Performance Engineering of Software Systems Joshua Slocum November 16, 2010 A Little Background Image rendering technique Simulate rays of light - ray
More informationRendering. 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
More informationIntroduction to 3D Graphics
Graphics Without Polygons Volume Rendering May 11, 2010 So Far Volumetric Rendering Techniques Misc. So Far Extended the Fixed Function Pipeline with a Programmable Pipeline Programming the pipeline is
More informationData Visualization. Fall 2017
Data Visualization Fall 2017 Vector Fields Vector field v: D R n D is typically 2D planar surface or 2D surface embedded in 3D n = 2 fields tangent to 2D surface n = 3 volumetric fields When visualizing
More informationIsosurface Rendering. CSC 7443: Scientific Information Visualization
Isosurface Rendering What is Isosurfacing? An isosurface is the 3D surface representing the locations of a constant scalar value within a volume A surface with the same scalar field value Isosurfaces form
More informationComputer 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
More informationPipeline 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
More informationApplications of Explicit Early-Z Culling
Applications of Explicit Early-Z Culling Jason L. Mitchell ATI Research Pedro V. Sander ATI Research Introduction In past years, in the SIGGRAPH Real-Time Shading course, we have covered the details of
More informationTopic 11: Texture Mapping 10/21/2015. Photographs. Solid textures. Procedural
Topic 11: Texture Mapping Motivation Sources of texture Texture coordinates Bump mapping, mip mapping & env mapping Topic 11: Photographs Texture Mapping Motivation Sources of texture Texture coordinates
More information3D vector fields. Contents. Introduction 3D vector field topology Representation of particle lines. 3D LIC Combining different techniques
3D vector fields Scientific Visualization (Part 9) PD Dr.-Ing. Peter Hastreiter Contents Introduction 3D vector field topology Representation of particle lines Path lines Ribbons Balls Tubes Stream tetrahedra
More informationComputer Graphics. Lecture 13. Global Illumination 1: Ray Tracing and Radiosity. Taku Komura
Computer Graphics Lecture 13 Global Illumination 1: Ray Tracing and Radiosity Taku Komura 1 Rendering techniques Can be classified as Local Illumination techniques Global Illumination techniques Local
More informationOrthogonal Projection Matrices. Angel and Shreiner: Interactive Computer Graphics 7E Addison-Wesley 2015
Orthogonal Projection Matrices 1 Objectives Derive the projection matrices used for standard orthogonal projections Introduce oblique projections Introduce projection normalization 2 Normalization Rather
More informationLevel 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,
More informationDirect Volume Rendering
Direct Volume Rendering CMPT 467/767 Visualization Torsten Möller Weiskopf/Machiraju/Möller Overview Volume rendering equation Compositing schemes Ray casting Acceleration techniques for ray casting Texture-based
More informationConsider a partially transparent object that is illuminated with two lights, one visible from each side of the object. Start with a ray from the eye
Ray Tracing What was the rendering equation? Motivate & list the terms. Relate the rendering equation to forward ray tracing. Why is forward ray tracing not good for image formation? What is the difference
More informationGraphics 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
More informationLECTURE 37: Ray model of light and Snell's law
Lectures Page 1 Select LEARNING OBJECTIVES: LECTURE 37: Ray model of light and Snell's law Understand when the ray model of light is applicable. Be able to apply Snell's Law of Refraction to any system.
More informationLets 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
More informationDirect Volume Rendering
Direct Volume Rendering Visualization Torsten Möller Weiskopf/Machiraju/Möller Overview 2D visualization slice images (or multi-planar reformating MPR) Indirect 3D visualization isosurfaces (or surface-shaded
More informationComputer graphics Labs: Blender (2/3) LuxRender: Interior Scene Rendering
Computer graphics Labs: Blender (2/3) LuxRender: Interior Scene Rendering University of Liège Department of Aerospace and Mechanical engineering Designed with Blender 2.76b LuxRender During the first tutorial
More informationGlobal Illumination CS334. Daniel G. Aliaga Department of Computer Science Purdue University
Global Illumination CS334 Daniel G. Aliaga Department of Computer Science Purdue University Recall: Lighting and Shading Light sources Point light Models an omnidirectional light source (e.g., a bulb)
More informationPipeline 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
More informationChapter 7 - Light, Materials, Appearance
Chapter 7 - Light, Materials, Appearance Types of light in nature and in CG Shadows Using lights in CG Illumination models Textures and maps Procedural surface descriptions Literature: E. Angel/D. Shreiner,
More informationCMSC427 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
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 informationVector Visualization. CSC 7443: Scientific Information Visualization
Vector Visualization Vector data A vector is an object with direction and length v = (v x,v y,v z ) A vector field is a field which associates a vector with each point in space The vector data is 3D representation
More informationPipeline Operations. CS 4620 Lecture 10
Pipeline Operations CS 4620 Lecture 10 2008 Steve Marschner 1 Hidden surface elimination Goal is to figure out which color to make the pixels based on what s in front of what. Hidden surface elimination
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 informationA Broad Overview of Scientific Visualization with a Focus on Geophysical Turbulence Simulation Data (SciVis
A Broad Overview of Scientific Visualization with a Focus on Geophysical Turbulence Simulation Data (SciVis 101 for Turbulence Researchers) John Clyne clyne@ucar.edu Examples: Medicine Examples: Biology
More informationChapter 6 Visualization Techniques for Vector Fields
Chapter 6 Visualization Techniques for Vector Fields 6.1 Introduction 6.2 Vector Glyphs 6.3 Particle Advection 6.4 Streamlines 6.5 Line Integral Convolution 6.6 Vector Topology 6.7 References 2006 Burkhard
More informationSchedule. MIT Monte-Carlo Ray Tracing. Radiosity. Review of last week? Limitations of radiosity. Radiosity
Schedule Review Session: Tuesday November 18 th, 7:30 pm, Room 2-136 bring lots of questions! MIT 6.837 Monte-Carlo Ray Tracing Quiz 2: Thursday November 20 th, in class (one weeks from today) MIT EECS
More information