Blender 3D：零基础到专业级-第1单元：背景

An orthographic view (or projection) of a 3D scene is a 2D picture of it in which parallel lines appear parallel, and all edges perpendicular to the view direction appear in proportion, at exactly the same scale.
::一个3D场景的正写视图 (或投影) 是一个2D图像,其中平行线呈现平行,并且所有垂直于视图方向的边缘呈现比例,在完全相同的尺度上.

Orthographic views are usually aligned with the scene's primary axes. Edges parallel to the view axis disappear. Those parallel to the other primary axes appear horizontal or vertical. The commonly used orthographic views are front, side, and top views, though back and bottom views are possible.
::写法视图通常与场景的主要轴对齐.与视图轴平行的边缘消失.与其他主要轴平行的边缘出现水平或垂直.常用的写法视图是前,侧和顶视图,尽管后和底视图是可能的.

Uniform scale makes an orthographic view very useful when constructing 3D objects, not only in computer graphics, but also in manufacturing and architecture.
::统一的尺度使得正写视图在构建3D对象时非常有用,不仅在计算机图形,而且在制造和建筑中也是如此.

Here's one way to think about the orthographic view:
::对于正写方式,

Imagine photographing a small 3D object through a telescope from a very great distance. There would be no foreshortening. All features would be at the same scale, regardless of whether they were on the near side of the object or its far side. Given two (or preferably three) such views, along different axes, you could get an accurate idea of the shape of the object, useful for "getting the feel" of objects in a virtual 3D world where you're unable to touch or handle anything!
::想象一下,从很远的距离用望远镜拍摄一个小的3D物体. 没有缩短. 所有特征都在相同的尺度上,无论它们是在物体的近侧还是远侧. 给定两个 (或最好是三个) 这样的视图,沿着不同的轴,你可以准确地了解物体的形状,这对于在虚拟3D世界中"感受"物体很有用,因为你无法触摸或处理任何东西!

Here is a drawing of a staircase:
::这里是楼梯的图:

and here are three orthographic views of the same staircase, each outlined in red:
::这里有三个相同楼梯的正写图, 每个都用红色勾勒出来:

The views are from the front, top, and left. Dashed lines represent edges that, in real life, would be hidden behind something, such as the left wall of the staircase. (Think of each view as an X-ray image.)
::图像是从前方,上方和左边的.划线代表了边缘,在现实生活中,隐藏在某个东西后面,例如楼梯的左侧墙壁. (把每一个图像看作X射线图像).

The leading edges of the steps are visible in both the front and top views. Note that they appear parallel and of equal length in 2D, just as they are in 3D reality.
::步骤的前边在前面和顶部的视图中都可见.请注意,它们在二维中是平行且长度相同的,就像它们在三维现实中一样.