| A | B |
|---|
| Perspective | mimics the way a human eye works and provides scenes that have a “natural” appearance |
| panning | move across a scene |
| x, y, and z | The scene may be rotated about any of its three axes |
| six | Different views can be produced by orthographic projection |
| origin | Where the axes intersect |
| coordinates | Numerical locations placed uniformly along the axes |
| Local | coordinate system-assign axes to particular object |
| World | coordinate system-assigns axes to the scene |
| Relative coordinates | an object starting at its current position |
| Absolute coordinates | used to transform an object relative to the origin |
| Arcs, ellipses, circles, curves, and freehand curves | basic 2D shapes |
| Polygons | plane figures made with three or more straight sides |
| Regular polygons | have equal length sides and equal angles |
| Splines | curves or polygons that are composed of segments that can be manipulated by control points |
| Typical parameters | center point, radius, height, width, etc |
| defaults | Values provided automatically by the software |
| Extrusion | allows you to create a 2D shape and then extend it along a path or curve to form a 3D object |
| lofting | where a series of curves (open or closed) is lofted or spaced parallel to each other, and then a surface is generated that connects the contours |
| Revolve or lathe | allow the user to create a 2D shape and then revolve it around an axis |
| Transformations | actions that scale, rotate, and move objects |
| Plug-ins | are independent programs or components usually supplied by third-party vendors |
| Atmospheric features | simulates atmospheric density |
| Orthographic (Parallel Projection) viewports | rovide an image in which the line of sight is perpendicular to the picture plane. |
| “Ortho" | the projectors extend straight off of the object, parallel to each other. |
| Points on the object’s edges | these are projected onto a picture plane where they form lines on the plane |
| Lines and surfaces that are inclined to the picture pla | these appear as foreshortened edges and surfaces on the plane to which they are projected |
| the axes | Lines drawn perpendicular to each other for the purpose of measuring transformation |
| the 2D Cartesian coordinate system | the horizontal axis called the X axis and a vertical axis called the Y axis |
| the coordinatesc | the numerical locations placed uniformly along the axes |
| All 3D modeling programs | contain certain basic geometric shapes that can be combined with or subtracted from other shapes to form more complex objects |
| Parameters | affect the size, placement, and orientation of the object |
| Extrusion, sweeping, or lofting | allows you to create a 2D shape and then extend it along a path or curve to form a 3D object |
| lofting | this modeling technique is used for modeling boat hulls and terrain |
| deformations | these are used to modify an existing shape and emulate the process of working a piece of clay |
| solid mode | 1. You can see colors (and some surface properties) and the impact that lights might have on the scene |
| plugins | independent programs or components usually supplied by third-party vendors that supplement the features of the original 3D program |
| Export | when 3d objects or scenes can be placed into another software program |
