Piercing Points

In this video, I demonstrate two methods for finding the piercing point, which is the exact location where a line segment intersects a plane, a common problem in descriptive geometry. I first walk through the auxiliary view method [00:18], which requires generating an edge view of the plane by projecting from a true length line to locate the intersection point and then project it back to the original views [02:49]. I then use the point of intersection to determine the visibility of the line in both the top and front views [03:23], indicating the hidden segment. For a faster approach, I also show the two-view method [05:38], which uses the apparent intersections in the two given views to quickly locate the piercing point. Video Chapters [00:00] Introduction: Finding the Piercing Point (Line intersecting a Plane) [00:18] Auxiliary View Method: Finding the Edge View of the Plane [00:29] Finding a True Length Line on the Plane [00:47] Setting up the Auxiliary View and Projecting the Plane [02:02] Projecting the Line into the Auxiliary View [02:49] Locating the Point of Intersection [03:23] Determining Visibility (Identifying Hidden Lines) [04:48] Reviewing the Auxiliary View Result [05:38] The Two-View Method for Finding the Piercing Point