Selected Bibliography Architectural Graphics | Page 96

PERSPECTIVE ELEMENTS The hori online (HL) is a horizontal line representing the interse ion of the picture plane (PP) and a horizontal plane p sing through the station point (SP). The cen er of vision (C) is the point on the horizon line at which t ecentral axis of vision (CAV) intersects the picture lane. pp '~-~ y ~\ ( . rou~e~ The q / : horizontal plane of reference ~h1ch heights can be measured in linear perspective. -.........""--~ Theground line (GL) is ahorizontal line representing the intersection of GP and the pictureplane (PP). The distance from GL to the horizon line (HL) is equal to the height of the station point (SP) above GP. Digital P erspectives 3D CAD and modeling programs, while following the mathematical principles of perspective, can easily create distorted perspective views. Keeping the central portion of a subject or scene within a reasonable cone of vision is therefore critical to avoiding such distortion. 90 I ARCHITECTURAl GRAPHICS