Photon Mapping Reference Material The slides have used/adapted - - PowerPoint PPT Presentation

Photon Mapping

Reference Material

The slides have used/adapted material from the following references: Slides on Photon Mapping by Jan Kautz (web4.cs.ucl.ac.uk/teaching/4074/archive/.../04_photon_maps.pdf) Slides on Photon Mapping by Bill Clark (http://penguin.ewu.edu/cscd570/2011/PDFNotes/PhotonMapping.pdf)

Photon Mapping

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Photon Mapping

Ray Tracing

• Cast a ray from the eye through each pixel
• Trace secondary rays (light, reflection, refraction)

Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

Introduction

Photon Mapping

Introduction

• Store photons

– position + light power + incoming direction

Photon Mapping

Introduction

• Efficiently store photons for fast access
• Use hierarchical spatial structure (kd-tree)

Photon Mapping

Introduction

• Cast primary rays
• For secondary rays

– reconstruct irradiance using k closest photons

• Combine with irradiance caching and other techniques

Photon Mapping

Introduction

Photon Mapping - Caustics

• Special photon map for specular reflection and

refraction

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Photon Mapping

What is a Photon?

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

Photon Mapping

Photon Mapping

Photon Mapping

Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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Photon Mapping

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www.bennolan.com

Photon Mapping

Photon Mapping

Realistic Image Synthesis Using Photon Mapping Realistic Image Synthesis Using Photon Mapping

Realistic Image Synthesis Using Photon Mapping

Realistic Image Synthesis Using Photon Mapping

Foreword by Pat Hanrahan

Realistic Image Synthesis Using Photon Mapping

Henrik Wann Jensen Jensen

The creation of realistic three-dimensional images is central to

computer graphics. Photon mapping, an extension of ray tracing, makes it possible to efficiently simulate global illumination in complex scenes. Photo mapping can simulate caustics (focused light, such as shimmering waves at the bottom of a swimming pool), diffuse inter-reflections (e.g., the `bleeding' of colored light from a red wall onto a white floor, giving the floor a reddish tint), and participating media (e.g., clouds or smoke). This book is a practical guide to photon mapping; it provides both the theory and the practical insight necessary to implement photon mapping and simulate all types of direct and indirect illumination efficiently. A K PETERS LTD.

Henrik Wann Jensen