:: Relief Clipping Planes For RealTime Rendering :: Matthias Trapp :: ::

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(No Transcript)
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Relief Clipping PlanesFor Real-Time Rendering
Matthias Trapp, Jürgen DöllnerHasso-Plattner-Inst
itute, University of Potsdam, Germany
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Results
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Motivation

• Relief Clipping Planes (RCP)
• Create more sophisticated cut-away views
• Enables non-regular cut-surfaces
• Contributions
• New clip plane parameterization
• Automatic cap-surface generation
• Implementation Goals
• Interactive configuration
• Use hardware acceleration

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Relief Clip-Plane Parameterization

• O Plane Origin
• U, V Direction Vectors
• S (sx,sy,sz) Scaling Vector
• OM Offsetmap

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Clipping Equation
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GLSL Fragment-Shader Source
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Multiple Clipping Planes
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Capping Openings The Goal
Assumption Input Mesh is SOLID.
http//www.bmbikes.co.uk/photos/museumphotos/Broke
n 20R60-6 Crank.jpg
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Capping The Process

• Goals
• Convey material / inner structure of the input
  solid
• Enable assisted modeling of cap-surface
  appearance
• Solution Polygonal Cap-Surface
• Directly derived from relief-clipping plane
• Rendering after the clipping pass

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Generating the Cap-Surface

• Phase A
• Dynamic Mesh Refinement on GPU Boubekeur05
• Perform displacement, shading, texturing,
• Phase B
• Clip away outside parts of the cap-surface

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Decision Problem

• Which point P of the cap-surface is inside a
  solid S ?
• Solution Volumetric depth test
• Needed Additional data structure
• Layered Depth Image (LDI) Shade98
• Image-based representation of shape
• Computed in pre-processing Everitt01

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Example of Layered Depth Image
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Volumetric Depth Test
Trapp08
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Conclusions

• Summary
• Advanced clipping approach
• Real-time rendering technique
• Fully implemented on GPU
• Drawbacks
• Needs additional data structure
• Needs high-tessellated cap-surface
• Future Work
• Generalized approach for clipping

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Thank You ! - Questions ?

• Contact
• Matthias Trapp
• matthias.trapp_at_hpi.uni.potsdam.de
• Jürgen Döllner
• juergen.doellner_at_hpi.uni.potsdam.de
• Computer Graphics Systems Group
• http//www.hpi.uni-potsdam.de/doellner/