Back in 2007 I developed a software tool that could generate technical drawings in a range of drawing projections from a 3D model with emphasis on oblique (both cabinet and cavalier, as well as custom obliques), planometric, dimetric, trimetric and one-point perspective.
I could describe them all as well as many more in terms of what the projected three axis look like on the projection plane. I described them all in terms of a scale on each of the three axis, as well as the angle two of the axis make with the projection plane’s horizontal.
Description of the projection in terms of the projected view of the three standard basis.
In terms of the actual development of the program I’m sure I could have done things a lot better. But I did learn a lot from the experience. The program worked to my needs and did what I wrote it to do so in that sense it was a success. The only downside would be that I did a lot of code rewriting of code that already existed out there (which probably did thinks better than I implemented them). Although since then I have done much more programming and had formal training so have learnt about better methods and practices.
The approach I took was basically import a DXF file, process the data to change its projection, and then export it as a DXF again. I used 3D polylines generated from my 3D model in Rhino and saved as DXF for the input. So I had to write a cutdown DXF reader/writer, as well as a way of storing this data internally and then doing the transformations on it then exporting it back into DXF so I could open it up in AutoCAD.
I only supported points, polylines, circles and arcs as this is basically all that Rhino exported from my model. To simplify the process of circles and arcs I internally converted them to a bunch of polylines as only for some projections they stayed as nice ellipses.
The user interface of the tool.
From a very simple model in Rhino, I use the silhouette tool to create the polylines which once impororted into my program produced the following samples.
Cabinet Oblique
Cavalier Oblique
Planometric
One Point Perspective
There is also a range of built in axonometric projections…
A range of axonometric projections are built in.
Finally here are some of my production drawings (from my 2007 HSC ITG Major Work (photos here)) that I used the software to create.
Oblique
One Point Perspective
Planometric
Trimetric
November 29, 2008 at 1:01 am |
[...] it for you from your 3D model. (So I actually wrote a small piece of software to help with this in this article). But to do so, I needed to understand the mathematics behind these graphical projections. So I [...]
July 27, 2009 at 11:54 am |
so can u share with us?
a very useful tools indeed~~~~
July 27, 2009 at 12:21 pm |
Yes I can, but…
The source code is really really really bad. It goes against everything I have since learnt in uni. Its not all that robust, while simple things worked like in the pictures I showed here, when I gave it something really complicated it failed. It was just an experiment for me, something I could try when doing a school assignment.
Also most of the work is actually reading the source file and writing the output file (and also converting circles and ellipses into many line segments). The actual transformation is just one simple matrix multiplication, but things like AutoCAD couldn’t seem to do that for me.
It won’t remove hidden lines either (because it will only accept wireframe’s as input).
If you still want it that is fine, but do you want the source (I did it in Visual Basic 2005) or executable?
Oh and also I wrote some commentary about this for my assignment, you can get that from, http://www.mediafire.com/?jqn4ln2tn2l. (It’s in Appendix A I think). Also those drawings above are available from http://box.net/andrewharvey4, the ITG_MajorProject_2007 files are the ones for that assignment.
Also I’m curious where is your source data coming from?
October 5, 2009 at 4:50 pm |
Hi,
My name is Matias and I’m teaching an architecture studio at Otis College of Art and Design in Los Angeles.
I need my students to show their 3D models in the view that your site calls “Cabinet Oblique”.
They all use Rhino, Autocad and Max but none of those programs shows you a model with that kind of view.
Your Viewit software seems to do exactly that.
Can you please tell me if they can download it and if so, from where? I tried the link to MEDIAFIRE but it didn’t work. Thanks
Matias
310 869-6336
October 5, 2009 at 8:00 pm |
Hi.
I’ve uploaded an executable to http://www.cse.unsw.edu.au/~amha119/ViewIt4.10.0.31.zip, and the source to http://www.cse.unsw.edu.au/~amha119/ViewItSrcBin.zip Please take note of the README and COPYING files contained in the zip file, and keep in mind that it was just an experiment/prototype. (Also I updated the link you said was broken. Thanks for reminding me.)
October 21, 2009 at 4:48 pm |
Thanks for sharing this software with me and my students. I understand you moved on and don’t want to hear much about problems with this program.
However, my students and I spent a good 40 combined hours trying to get a “cabinet projection” of a simple model and failed. The closest we got was a DXF file that that looks like a point on the Autocad screen. When selected, you can see that it’s not a point but many entities but it doesn’t let you zoom in or scale it up.
If you have a quick tip to share with us, we’ll greatly appreciate it. If not, we’ll have to give up.
Thanks anyway. MC
October 21, 2009 at 8:32 pm |
Try it on a simple model first (eg. a cube) and make sure it works as you want it there before feeding it a more complex model.
These are things you probably tried, but is the model coming from Rhino or AutoCAD? And are you exporting the lines/arcs (not surfaces) to an old DXF format (use R12)?
A video showing it in action is up at http://vimeo.com/7179885 but it probably won’t help. Its only in the 2nd half and really sped up, so if you are really keep you can download the mov and slow it down.