This Demonstration illustrates a three-view engineering drawing called first-angle projection.
In first-angle projection, the projectors originate as if radiated from the viewer's eyes and shoot through the 3D object to project a 2D image onto the plane behind it. First-angle projection is the ISO standard and is primarily used in Europe .
 Wikipedia. "Engineering Drawing." (Oct 26, 2013) en.wikipedia.org/wiki/Engineering_drawing.
Wolfram Demonstrations Project
Published: November 8 2013