# Definition of orthographic projection

The point of perspective for the orthographic projection is at infinite distance.

Foldlines are often included in the drawing and will be shown in the examples as phantom lines line dash dash line. But there is nothing to indicate how far the point is behind the frontal plane Df.

## Isometric projection definition

It depicts a hemisphere of the globe as it appears from outer space , where the horizon is a great circle. Orthogonal views provide a means for describing the exact size and shape of an object. Until the evolution of 3D solid modeling, it was difficult to define these parts accurately in three-dimensional space. The six planes that make up the box are defined as the principal projection planes. The distance that the point is behind the frontal plane Df is the same whether you view the point from the top or from the side. The subscripts Dpr and Dpl are often used to indicate whether the point is located with respect to the right or left projection plane. To demonstrate the concept of orthographic projection, we will begin by showing the projection of a single point in space. Missing View Projection To reinforce the theory of orthographic projection, most of the initial problems will be 'missing view' problems. Note that the point could have been located with respect to the other three planes that make up the box as well. If the top view was given, Df would be known. You could not learn the simple words until you knew the letters which formed them. The same concept can be applied to learning the graphics language. To maintain the relationships between views, the projection planes cannot be separated, only unfolded about the edges created by the intersection of the planes.

Consider the surface with a fixed triangular shape. Later, more complex words were added to your vocabulary and the process conintinued. Other names for these views include plan, elevation and section.

A normal line is a line in space which is parallel to two of the principal planes and perpendicular to the third. Only then could you draw the missing side profile view.

Rated 5/10
based on 109 review

Download