Graphics Pipeline and Hierarchical Modeling

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Graphics Pipeline and Hierarchical Modeling

• Advanced Multimedia Technology Computer Graphics
• Yung-Yu Chuang
• 2005/12/14

with slides by Brian Curless, Zoran Popovic,
Robin Chen and Doug James
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Announcements

• Final project is online and due on 1/11.

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Review of graphics pipeline
Transformation
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Review of graphics pipeline
Projection clipping
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Review of graphics pipeline

• Rasterization
• Visibility

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Review of graphics pipeline

• Shading

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Visibility Algorithms

• Painters algorithm
• Ray casting
• Z-buffer
• Binary space partitioning

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Ray casting
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Z-buffer algorithm
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Z-buffer algorithm
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Z-buffer algorithm
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Binary space partition
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BSP tree
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BSP tree construction
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BSP tree display
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Back face culling
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Shading

• Shading model determines the color values for
  each pixel
• To accurately determine the right color is a hard
  problem because photons can
• Interact with the atmosphere
• Be absorbed or reflected by a surface
• Bounce around and around within the scene
• Here, we are going to use a widely used fast
  approximation of reality called the Phong shading
  model

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Setup
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Emissivity
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Ambient reflection
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Wavelength dependence
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Surface types
rough surface
smooth surface
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Diffuse reflection
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Diffuse reflection
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Diffuse reflection
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Diffuse reflection
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Specular reflection
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Specular reflection
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Specular reflection
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Put it together
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Choosing the parameters
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Flat shading
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Gouraud shading
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Phong shading
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Review of graphics pipeline
Transformation
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Review of graphics pipeline
Projection clipping
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Review of graphics pipeline

• Rasterization
• Visibility

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Review of graphics pipeline

• Shading

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Hierarchical modeling a robot arm
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First implementation
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Better implementation
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OpenGL implementation
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Hierarchical modeling
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Implementation
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Human with hands
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Better implementation
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OpenGL implementation