AutoCAD/CAD

Advertisement


Question
scan
scan  
QUESTION: In CAD I can create a perspective view of a perfectly square box that was an ISO view using the camera tool. Is it possible to reverse that and convert a perspective view into an ISO view? For example: a raster-line perspective hand sketch of a building, scanned into vector lines, and then pushed into an ISO view where one side can be viewed as a 2d elevation or plan-view cut from the top? Thanks very much for your help. Here is a scanned image of a perspective drawing. I would like to convert this into a floor plan view and elevations. Accuracy of the lines can be adjusted once they are approximately in the right position for the floor plan view and elevations.

ANSWER: Ron,
I don't have any experience with the camera tool.  However, what I think you're asking me is if you can convert a perspective image which is no longer a 3D dwg to an isometric image.  My answer to that is that as far as I know I would guess not.  I believe you would have to regain access to the 3D model, select a preset isometric view and render the model again to create a new isometric image of model.  Or if the camera has an isometric option, you could use that tool to create a new isometric image.  But I'm guessing that because it's a camera, an isometric image is not something any camera can create.  You can also try the question pool to see if there is somebody there to help you with this question.
Several tutorial videos of the camera tool for AutoCAD 3D Camera Command are available on YouTube.

https://www.youtube.com/results?search_query=AutoCAD+3D+Camera+Command+Tutorial+%7C+AutoCAD+2010

Have a great summer!

Bill

---------- FOLLOW-UP ----------

QUESTION: Thanks for your help Bill. I just wanted to get your opinion about what I have concluded so far. I don't know too much about geometry, and the only program I know is Revit. There certainly is no way to trace a raster image of a perspective drawing in a Revit perspective view. Revit perspective views are derived from 2d floor-plans that are actually top-down views of 3D isometric wire-frame models. I soon realized that the only way to create perspective vector lines by tracing a perspective raster image was to use a program that ALLOWED tracing of a perspective image, while created a 3d model, in a perspective view, all at the same time. I imagined that the view creating those vector perspective lines would need to be lined-up with the degree of perspective in the image. I picked a geometry program that is known to be the easiest to learn, "SketchUp." I gave myself a crash-course in how to use SketchUp. (BTW I was really hoping SketchUp would fail to do the job because compared to Revit, SketchUp seems like a program for hobbyists or amateurs.) Anyway, I could trace lines over an image in SketchUp, but apparently not while being in the same perspective drawing view that you usually draw in, only a 2d view. Not only that, but in SketchUp, it appeared to me that there was only one perspective with no adjustment of the camera length to match a perspective in an image. So I abandon SketchUp. Then I spent a couple of hours ready about geometry programs, and it appears that one of the most popular and professional is Rhino 5. Easy to download the 60-day trial and it also uses Vray. So here I am looking at Rhino 5, knowing that it will probably do everything I want, but learning to use it is a different story. What do you think Bill?

ANSWER: I am not a Revit guy or a Rhino guy.  I'm an AutoCAD guy in an AutoCAD forum.  Anyway, we have a guy on our team that uses Sketchup to render our buildings.  It works great, and he's really good with it.  As far as making a 2-D image of what you can see in a 3-D program, it's really quite simple on a PC.  Maximize or go to full screen, zoom in on the object making sure that all the linework you want to save is showing on screen.  Then, just press the Prt Scr key.  That will save the image to your clipboard.  Then go to Windows Paint (pbrush.exe) and Ctrl+V to paste the image into your Paint window.  Then save the image as a jpg, and import it into whatever program you're drawing your 2D prospective or isometric view and trace over the top of the image.  I do this a lot for many different aspects of architecture, mostly in site plans for contour lines and utility lines, and sometimes for buildings if I'm working off an aerial view from Google Earth or Google Maps.  

Have fun!



---------- FOLLOW-UP ----------

QUESTION: Not sure how we got so far apart on what we were talking about, but this might give you an idea of what I am talking about.

https://www.youtube.com/watch?v=Tp8379Y1Mvo

Answer
Well, now, you taught me something.  Rhino can draw in perspective.  Is that right?  In AutoCAD, you can draw in Isometric, but to get a perspective view, you have to set up a camera and take a picture of your 3D model.  There might be a way to set up a background image(referred to as wallpaper in Rhino) in a 3D drawing in AutoCAD, similar to the way I mentioned before for 2D, but I haven't tried that yet, myself.  

Bill DeShawn
http://my.sterling.net/~bdeshawn  

AutoCAD

All Answers


Answers by Expert:


Ask Experts

Volunteer


Bill DeShawn

Expertise

I can address all 2-D questions and some 3-D questions. I do programming in AutoLISP if it doesn`t involve solid modeling. I can also address menu customization issues and can help you find answers to questions I can`t answer by taking your question directly to Autodesk via their newsgroups.

Experience

I used to do electronic and mechanical design for a flat panel monitor manufacturer, and now I do architectural drafting for an architect. I did and do AutoLISP and menu customization and take pride in making my lisp routines to do the work exactly the way the client likes them done.

Publications
I had a routine published in CADENCE magazine (no longer in publication and taken over by CADALYST). Some of my routines are published on my website at http://my.sterling.net/~bdeshawn

Education/Credentials
Certified completion of AutoCAD courses, AutoCAD employment experience since 1992

©2016 About.com. All rights reserved.