UCTION constructed by drawing projection lines fron object to a projection plane (the surface projection is being created). The shape of \\( t \\) affected by the orientation of the projer respect to the projection plane. These lin from a point source (e.g., light rays fron bright bulb; Fig. 3-1a), or they may b another (e.g., light rays from a distant Parallel projection lines can be per projection plane (Fig. 3-1b) or obliqu plane (Fig. 3-1c). If the projection line another and are perpendicular to the resulting projected image is calle projection (Fig. 3-1b). The use of ort for solving problems involving the areas of planes, and the angles betw the subject of descriptive geome problems in descriptive geometry ir angles and lengths in a scaled dra geometry of a structure to scale. showed developed the concept of a be specified with respect to a reference wever, we have primarily described linear or planar geologic elements observed and measured. In many measurement of a geologic feature is e attitude of the f