László Szirmay-Kalos Budapesti University of Technology and Economics Department of Control...
-
Upload
emmalee-hinkley -
Category
Documents
-
view
219 -
download
1
Transcript of László Szirmay-Kalos Budapesti University of Technology and Economics Department of Control...
László Szirmay-Kalos
Budapesti University of Technology and EconomicsDepartment of Control Engineering and Information Technology
andGraphisoft R&D
Photorealistic Image Synthesisin CAD Systems
(IKTA3 00101/2000)
Photorealistic Image Synthesis in CAD systems 2
The Project• A research project between BUTE and Graphisoft• Research topic: global illumination in architectural CAD
systems• January 2001 – April 2002• Homepage: www.iit.bme.hu/~szirmay/ikta/index.html• Participants:
– Project leader: dr. László Szirmay-Kalos (BUTE)– Advisors: dr. László Szirmay-Kalos (BUTE) and László
Sparing (Graphisoft)– PhD students: György Antal, Ferenc Csonka (Graphisoft),
László Kovács (BUTE), Benedek Balazs (BUTE), Szécsi László (BUTE)
– Others: dr. Horváth Tamás (BUTE), Csaba Kelemen• The main results: scientific research and a new framework
called RenderX for testing and implementing global illumination algorithms
Photorealistic Image Synthesis in CAD systems 3
Graphisoft and ArchiCAD• Graphisoft was promoted in 1982• It is the third software company in the
AEC sector (Architecture, Engineering and Construction)
• The leading product of Graphisoft is the ArchiCAD, which is an object oriented, 3D design software for the architecture and building industry
Photorealistic Image Synthesis in CAD systems 4
Outlines
• Objective of the project
• Photorealistics image synthesis fundamentals
• The result of the project
• Products and applications
Photorealistic Image Synthesis in CAD systems 5
Goal of the project
• Global illumination image synthesis– Must be physically accurate– Solving the rendering equation– Identify all potential light paths– Conventional methods took hours to render
• Interactive naviagation and animation– must produce new images in seconds
Photorealistic Image Synthesis in CAD systems 6
The aim of image synthesis
• In the virtual world, a virtual camera makes the photo of the scene.
The camera looks into the world through a window
The camera sees the scene like this
Photorealistic Image Synthesis in CAD systems 7
The rendering equation
L= Le+ T L
Photorealistic Image Synthesis in CAD systems 8
How does the Nature work?• 100 W light bulb emits 1042 photon per second
• The calculation of the intersected patches, that the photons hit is determined parallel with the speed of light
• The photons are absorbed randomly or reflected into a random direction
• Very little fraction of the emitted photons arrive finally to the eye
Photorealistic Image Synthesis in CAD systems 9
Local Illumination
Top: sharp (left) and soft (right) shadows on local illumination imagesDown: the global illumination image
(H. W. Jensen, 1996)
Photorealistic Image Synthesis in CAD systems 10
Global Illumination
• Identify all the possible light paths via multiple reflections, from the light source to the eye
Photorealistic Image Synthesis in CAD systems 11
Global Illumination• Follow the light paths from the camera to the eye
with another method
(Szirmay-Kalos László, 2000)
Photorealistic Image Synthesis in CAD systems 12
Results• Publications in 2001:
– László Szirmay-Kalos, Ferenc Csonka, György Antal: Global Illumination as a Combination of Continuous Random Walk and FiniteElement Based Iteration, Eurographics Conference, 2001
– Csaba Kelemen, László Szirmay-Kalos: A Microfacet Based Coupled Specular-Matte BRDF Model with Importance Sampling,Eurographics Conference, 2001
– Csaba Kelemen, László Szirmay-Kalos: Simple and Robust Mutation Strategy for Metropolis Light Transport Algorithm, Dagstuhl Seminar on Monte-Carlo Methods in Rendering, 2001
– György Antal, László Szirmay-Kalos, Ferenc Csonka, Csaba Kelemen: Multiple Strategy Stochastic Iteration for Architectural Walkthroughs, Dagstuhl Seminar on Monte-Carlo Methods in Rendering, 2001
– Ferenc Csonka, László Szirmay-Kalos György Antal: Cost-Driven Multiple Importance Sampling for Monte-Carlo Rendering, MCM Conference, Salzburg, 2001
– György Antal, László Szirmay-Kalos, Ferenc Csonka, Csaba Kelemen: Multiple Strategy Stochastic Iteration for Architectural Walkthroughs, Technical Report, TR-186-2-01-17, Vienna, 2001
– Csaba Kelemen, László Szirmay-Kalos: Simple and Robust Mutation Strategy for Metropolis Light Transport Algorithm, Technical Report, TR-186-2-01-18, Vienna, 2001
– Ferenc Csonka, László Szirmay-Kalos György Antal: Cost-Driven Multiple Importance Sampling for Monte-Carlo Rendering, MCM Conference, Technical Report, TR-186-2-01-19, Vienna, 2001
– László Szirmay-Kalos, László Kovács, Ali Mohamed Abbas: Testing Global Illumination Methods with Analytically Computable Scenes Winter School of Computer Graphics Conf., 2001
– Roel Martínez, László Szirmay-Kalos, Mateu Sbert, Ali Mohamed Abbas: Parallel Implementation of Stochastic Iteration Algorithms, Winter School of Computer Graphics Conf., 2001
– László Szirmay-Kalos, György Antal, Mateu Sbert: Progressive Light Path Development, Winter School of Computer Graphics Conf., 2001
Photorealistic Image Synthesis in CAD systems 13
Results• Publications in 2002:
– György Antal, László Szirmay-Kalos, Ferenc Csonka: Weighted Multipass Method Based on Stochastic Iteration and Random Walk Methods, Winter School Of Computer Graphics Conference, 2002
– Csaba Kelemen, László Szirmay-Kalos, György Antal, Ferenc Csonka: Simple and Robust Mutation Strategy for Metropolis Light Transport Algorithm, Eurographics Conference, 2002
– György Antal, László Szirmay-Kalos, Ferenc Csonka: Hemicube Shooting for Non-Diffuse Global Illumination, Spring Conference on Computer Graphics, 2002
– László Szirmay-Kalos, Vlastimil Havran, Balázs Benedek, László Szécsi: On the Efficiency of Ray-shooting Acceleration Schemes, Spring Conference on Computer Graphics, 2002
• Submitted papers:– György Antal, László Szirmay-Kalos, Ferenc Csonka, Csaba Kelemen: Multiple Strategy Stochastic Iteration for
Architectural Walkthroughs– Ferenc Csonka, László Szirmay-Kalos, György Antal: Cost-Driven Multiple Importance Sampling for Monte-Carlo
Rendering– Ferenc Csonka, László Szirmay-Kalos, Csaba Kelemen, György Antal: Dependent Tests driven Filtering in Monte-Carlo
Global Illumination– György Antal, Ferenc Csonka: An Efficient And Robust Framework for Global Illumination Algorithms, 1st Hungarian
Conference on Computer Graphics, 2002– Ferenc Csonka, György Antal: A Multi-Phase Energy Preserving Filtering Method for Architectural Scenes, 1st Hungarian
Conference on Computer Graphics, 2002
Photorealistic Image Synthesis in CAD systems 14
Applications• The CAD programs connect to the global illumination application via 3D File
formats: SCE, 3DS, VRML, MGF.
RayBundle
RenderX
SCE
3DS, VRML,MGF,...
SceWriterArchiCAD
3D Studio
Maya
Photorealistic Image Synthesis in CAD systems 15
RenderX
SCE3DSVRMLMGF
WireframeLocal IlluminationRay-TracingRay Bundles (Gouraud)Ray Bundles (Phong)Path TracingBidirectional Path TracingMetropolis...
ScalingWardetc.
Photorealistic Image Synthesis in CAD systems 16
Stochastic Iteration Finite element methods
15 K patches5 seconds1220
Photorealistic Image Synthesis in CAD systems 17
Stochastic Iteration with Phong shading
Photorealistic Image Synthesis in CAD systems 18
Production qualityMonte-Carlo methods
Photorealistic Image Synthesis in CAD systems 19
Walkthrough Animation• Place camera
keyframes in ArchiCAD,
• save scene, • calculate global
illumination animation in RenderX