Tutorial
3D Clipping

1. Suppose a view volume is defined by:
   

     near = 1
     far = 4
     left = -1
     right = 1
     bottom = -1
     top = 1
   

   Clip the line P1(0,2,0) P2(1,0,-3) to the view volume, in VCS.
   
   
2. Will a straight line in space always project to a straight line in a perspective image? Investigate this by considering the line segment P0(x1,y1,z1) P1(x2,y2,z2). Starting with the parametric form for the line P0 P1, show that the projected image of this parametric line is also a parametric line equation which can be expressed in terms of the projected endpoints, P0'P1'. Assume a simple projection transformation, namely: x'=xd/z, y'=yd/z, z'=d.