Graphics
cgvr.korea.ac.kr Graphics Lab @ Korea University
Model Construction
고려대학교 컴퓨터 그래픽스 연구실
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Model Construction
Interactive Modeling Tools CAD programs Subdivision surface editors
Scanning Tools CAT, MRI, laser, magnetic, robotic arm, etc.
Computer Vision Stereo, motion, etc.
Procedural Generation Sweeps, fractals, grammars
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Interactive Modeling Tools
User Constructs Objects with Drawing Program Menu commands, direct manipulation, etc. CSG, parametric surfaces, quadrics, etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Interactive Modeling Tools
Example: Mechanical CAD
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Model Construction
Interactive Modeling Tools CAD programs, subdivision surface editors
Scanning Tools CAT, MRI Laser Range Scanning Magnetic, robotic arm
Computer Vision Stereo, motion, etc.
Procedural Generation Sweeps, fractals, grammars
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Scanning Tools
Acquire Geometry of Objects with Active Sensors CAT/MRI Laser range scanner Magnetic sensor Robotic arm Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Scanning Tools
Acquire Geometry of Objects with Active Sensors CAT/MRI Laser range scanner Magnetic sensor Robotic arm Etc.
Color
Depth
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Scanning Tools
Acquire Geometry of Objects with Active Sensors CAT/MRI Laser range scanner Magnetic sensor Robotic arm Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Scanning Tools
Acquire Geometry of Objects with Active Sensors CAT/MRI Laser range scanner Magnetic sensor Robotic arm Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Model Construction
Interactive Modeling Tools CAD programs Subdivision surface editors
Scanning Tools CAT, MRI, laser, magnetic, robotic arm, etc.
Computer Vision Stereo Motion
Procedural Generation Sweeps, fractals, grammars
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Computer Vision
Infer 3D Geometry from Images Stereo Motion Constraints Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Computer Vision
Infer 3D Geometry from Images Stereo Motion Constraints Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Computer Vision
Infer 3D Geometry from Images Stereo Motion Constraints Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Model Construction
Interactive Modeling Tools CAD programs, subdivision surface editors
Scanning Tools CAT, MRI, laser, magnetic, robotic arm, etc.
Computer Vision Stereo, motion, etc.
Procedural Generation Sweeps Fractals Grammars
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Model Construction
Goal: Describe 3D models algorithmically
Best for Models Resulting from ... Repeating processes Self-similar processes Random processes
Advantages: Automatic generation Concise representation Parameterized classes of models
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Sweep
Example: Seashells Create 3D polygonal surface models of seashells Sweep generating curve around helico-spiral axis
Helico-spiral definition:
i+1i
ri+1 ri r
zi+1 zi z
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Sweep
Generate Different Shells by Varying Parameters
Different helico-spirals Different generating curves
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Fractal
Defining Property: Self-similar with infinite resolution
Mandelbrot Set
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Fractal
Useful for Describing Natural 3D Phenomenon Terrain Plants Clouds Water Feathers Fur Etc.
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Fractal Generation
Deterministically Self-Similar Fractals Parts are scaled copies of original
Initiator: start with a shape Generator: replace subparts with scaled copy of original
Statistically Self-Similar Fractals Parts have same statistical properties as original
Initiator: start with a shape Generator: replace subparts with a self-similar random
pattern
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Deterministically Self-Similar Fractal
Useful for Creating Interesting Shapes
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Deterministically Self-Similar Fractal
Useful for Creating Interesting Shapes
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Statistically Self-Similar Fractal
Useful for Creating Mountains
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Statistically Self-Similar Fractal
Useful for Creating 3D Plants
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Grammar
Generate Description of Geometric Model by Applying Production Rules Useful for creating plants
Example:
Tree Branch Tree | Leaf
Branch Cylinder | [ Tree ]
C[CL]C[C[CL][CL]]C[[CL][CL]] C[*]C[*][*]
cgvr.korea.ac.kr
CGVR
Graphics Lab @ Korea University
Grammar
Useful for Creating Plants