Repository logo

Infoscience

  • English
  • French
Log In
Logo EPFL, École polytechnique fédérale de Lausanne

Infoscience

  • English
  • French
Log In
  1. Home
  2. Academic and Research Output
  3. EPFL thesis
  4. Traversing Time Dependent Light Fields for Daylight Glare Evaluation
 
doctoral thesis

Traversing Time Dependent Light Fields for Daylight Glare Evaluation

Wasilewski, Stephen William  
2023

To understand how daylight gives shape and life to architectural spaces, whether existing or imagined, requires quantifying its dynamism and energy. Maintaining these details presents a challenge to simulation and analysis methods that flatten data into discrete images or virtual sensor points from a point and time. To address this challenge, this thesis presents a new method for sampling and evaluating simulated daylight. It is intended as a bridge between image-based and sensor-based methods; one that can produce image-level high accuracy directional distribution data with much shorter simulation times that are closer to sensor-based methods. Instead of producing a fixed grid of points, pixels, and sun directions, an iteratively guided sampling approach structured by the discrete wavelet transformation captures the distribution of light incident on a viewpoint with a variable density. By storing the direction vector and effective solid-angle of each sampled ray, the data can be directly evaluated for any luminance-based quantity and view direction. Coupled with daylight coefficients, where the contributions from regions of the sky-dome are recorded rather than associating a value to every possible sky distribution, these methods reduce simulation time at three stages by reducing the number of samples. With fewer samples, it takes less time to render, less time to combine with sky values, and less time to evaluate potential glare sources. Through a series of simulated reference validations, this thesis shows that the proposed method can reproduce the value predicted by a high quality reference simulation in a small fraction of the time. The method achieves higher accuracy results compared to those of existing simulation methods that rely on simplifications. The method is robust across a wide range of daylight conditions and can be tuned to the desired scope of the output. The method can be applied to render a single image in high detail or used to calculate glare metrics in order to evaluate a whole building zone. This method enables a more complete characterization of daylight and visual comfort across an occupied zone; one that is less biased by proxy measurements, representative point selection, or assumptions about glare-causing pathways. Using these methods, we can more reliably understand how daylight will respond to proposed interventions, which should be useful for guiding design, regulatory standards, and improving performance.

  • Files
  • Details
  • Metrics
Type
doctoral thesis
DOI
10.5075/epfl-thesis-10118
Author(s)
Wasilewski, Stephen William  
Advisors
Andersen, Marilyne  
•
Wienold, Jan  
Jury

Prof. Jean-François Molinari (président) ; Prof. Marilyne Andersen, Dr Jan Wienold (directeurs) ; Prof. Wenzel Jakob, Dr. David Geisler-Moroder, Prof. Christoph Reinhart (rapporteurs)

Date Issued

2023

Publisher

EPFL

Publisher place

Lausanne

Public defense year

2023-01-16

Thesis number

10118

Total of pages

203

Subjects

daylight

•

simulation

•

rendering

•

CBDM

•

glare

•

visual comfort

•

validation

•

lightfield

EPFL units
LIPID  
Faculty
ENAC  
School
IA  
Doctoral School
EDCE  
Available on Infoscience
January 16, 2023
Use this identifier to reference this record
https://infoscience.epfl.ch/handle/20.500.14299/193906
Logo EPFL, École polytechnique fédérale de Lausanne
  • Contact
  • infoscience@epfl.ch

  • Follow us on Facebook
  • Follow us on Instagram
  • Follow us on LinkedIn
  • Follow us on X
  • Follow us on Youtube
AccessibilityLegal noticePrivacy policyCookie settingsEnd User AgreementGet helpFeedback

Infoscience is a service managed and provided by the Library and IT Services of EPFL. © EPFL, tous droits réservés