In this chapter, students will be able to understand the terminology used in 3D modeling, define the most popular types of 3D modeling systems, apply Boolean operations to 3D objects, understand the role planning plays in building a constraint-based model.
Trang 1
3D Modeling and Display
Trang 2
3D Model Types
Wireframe
Surface
Solid
Parametric
Trang 3
Wireframe Models
3D model created
with ordinary lines,
circles, arcs, etc., to
represent edges
Only vertex and
edge data is stored
No shading, hidden
line removal
Trang 4
Surface Models
Model with surface objects
Meshes frequently used to
represent surfaces
Surface, edge, & vertex
information stored
Shading, hidden line
removal
Useful for modeling shapes
with complex curvature
(e.g., hull forms, airfoils,
automobiles)
(10,100,100)
(0,0,0)
X Z
Surface Model
6 meshed surfaces
Trang 5
Solid Models
Model with solid objects
(e.g., primitives, sweeps)
Database contains
information about vertices,
edges, surfaces, and the
space enclosed by the
surfaces
properties
Shading and hidden line
removal
(100,100,100)
(0,0,0)
X Z
Solid Model
1 primitive
Trang 6
3D Display
Wireframe
Hidden line / hidden surface
Shaded
Rendered
NOTE:Display refers to the way that 3D objects
appear on the display device (i.e., the computer monitor)
Trang 7
Wireframe Display
Model edges and contours are visible
(Model may be wireframe, surface, solid
or parametric)
Simpler and faster than shaded display Tradeoff between complexity and
speed
Trang 8
Hidden Line/Surface Display
Hidden line/surface removal class of algorithms
used to determine model edges, surfaces, or
volumes that are visible or invisible from a
particular viewpoint
wireframe wireframe
surface surface
Trang 9
Shaded Display
Display technique that hides hidden lines and applies flat colors to visible surfaces
Trang 10
Rendered Display
Single, shaded view of a 3D model to which
colors, materials,
textures and lighting
have been added
Trang 12
3D Modeling and Display
Akahaw Huwa!