Perspective in AutoCAD
  1. The perspective imaging program built into AutoCAD will prove itself easier to do than manually constructing a perspective drawing of your project the old fashion way. AutoCAD's DVIEW command stands for "Dynamic VIEW." This means that as you manipulate the parameters of perspective, you will be able to dynamically adjust your view and the appearance of the drawing. This gives you a very powerful ability to select the most pleasing view of the group of buildings.
  2. The first step is to bring the drawing back into the plan view. Make sure that you are in the World Coordiante System - type UCS<RET><RET> (note the two carriage returns).  Then type PLAN <RET><RET> (note the two carriage returns). Zoom to extents, and then zoom to half of the extents by typing Z <RET> .5X <RET><RET>.
  3. Type DV<RET> on the keyboard (or select "View" from the pull-down menu then "3D Dynamic View").
  4. At the prompt "Select Objects:" select the area of the drawing you want to view during the preparation of the perspective viewing by selecting objects by placing a "window" around the entire drawing image.
  5. At this point you will successively select the "TArget" point (where you are looking toward), and the "CAmera" point (where you are looking from). To do this, type PO <RET> (this stands for "POints"). You will be prompted to select the location of the "TArget" point first. Pick one corner of the building as your "TArget" point. Then you will be prompted to select the "CAmera" point in the same manner. The "CAmera" point means where your eye is placed in relation to the "TArget" point. In this exercise, to set the "CAmera" point, pick the diagonally opposite corner of the building for the "CAmera" point. The view will automatically change to align with the camera to target vector.  Note that both target and camera are located at the ground level ("0" height elevation).
  6. Next you will adjust the distance between the "CAmera" point and the "TArget" point. Type D <RET>. This will bring up a slider bar at the top of the screen where you can slide a pointer left or right until you have a satisfactory size to the image. The Distance command will place your eye on the diagonal line established by selecting the "TArget" and "CAmera" POints, but will increase or decrease the actual distance between them. The "TArget" remains where it was set, and the "CAmera" moves along the line. The effect is that the object you are looking at will become smaller or larger.  Once the Distance between the "TArget" and "CAmera" has been set, AutoCAD will switch to perspective viewing, so that parallel lines converge, and vanishing points are established.
  7. Next you will change the angle of the line between the "CAmera" point and the "TArget" point, through the "CAmera" command. Type CA <RET> then move the mouse to fly up and around the perspective dynamically.  Do not dip the cursor below the center of the screen, or you will be looking from under the drawing.
  8. If you need to enlarge the image on the screen, you can change the distance again - type  D<RET>  and use the slider bars.  You cannot use the standard AutoCAD Zoom command.  The DVIEW Zoom command is different from the standard AutoCAD "Zoom" command - it allows you to change the length of your imaginary lens in your imaginary camera, that is the lens to film distance.  As you might expect, a 50mm lens is a so-called "normal lens," a 30mm lens is a "wide angle," for example, and a 800mm lens is a "telephoto lens." Note that as you move your pointer mouse back and forth over the slider bar the status line shows the resultant lens length, and the view will dynamically change to show you what it will look like. The results of the view in terms of potential distortion will follow that of an actual camera. What is actually happening is that the "cone of vision" widens with a shorter lens, and narrows with a longer lens. The DVIEW Zoom command does not affect the distance between the "CAmera" point and the "Target" point. This command will possibly take some time to get used to. You should try out various lens lengths to see how it varies the perspective view. I suggest a relatively short lens length, say about 30 mm, because it increases the dramatic angularity of the perspective.
  9. Type <RET> to end the perspective setup.  This will bring you back to the Command: prompt and out of the perspective imaging program.  The drawing will still appear in perspective view, and you will not be able to edit it.  You will need to return to an orthogonal view (i.e., a non-perspective view) to edit your drawing.
  10. Once you are pleased with your perspective view and you are through tinkering with it, you should save it as a memorized "view." To do this, type V <RET>.  This will bring up the "View Control Dialogue Box." Select the "New" button. Type in the name of this view P1. Then pick the "Save View" button. Then pick the "OK" button. This view in its perspective mode will then be able to be brought back "restored" in any viewport.
  11. To allow editing of the drawing, you should return to the "plan" view by typing PLAN <RET><RET>.