Inverse Lighting with a Monte Carlo Method

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Inverse Lighting with a Monte Carlo Method

• Patrick Poulingeas, Vincent Jolivet, Dimitri
  Plemenos
• LMSI
• Equipe Modélisation et Infographie Intelligente

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Usual Lighting Process
designeridea of lighting
Data Scene Geometry Material properties
Specifications given by the designer Light
source(s) position(s) Light source(s) physical
properties
If the scene doesnt agree the designer
Rendering
Scene
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Inverse Lighting Process
Data Scene Geometry Material properties
designeridea of lighting

• Inverse Lighting Method computing
• Possible light source(s) position(s)
• Possible light source(s) properties

Rendering
Scenes
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Finding the Light Source Positions
Potential light source positions found by a
Monte Carlo method
Patches to light
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Finding the Light Source Positions

• Reducing the number of potential light
  sources with
• A heuristic using form factors computed in
  radiosity
• Constraining the lights to be at the ceiling

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Example of solution found
The patches to be lit are painted in purple in
the right picture
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Another example of solution found
The patches to be lit are painted in purple in
the right picture