I need an alternative to Visio for making diagrams (particularly signal processing block diagrams) that includes some kind of custom stencils + connection points. I just spent 2 hours learning bits and pieces of Dia only to find that it has no rotational capabilities, not even 90 degree rotations. Otherwise it's great.
Any suggestions?
Here is an annotated list of alternatives to MS Visio. SmartDraw is considered a close match to Visio.
Otherwise it includes:
On the Mac, I'm a big fan of OmniGraffle from The Omni Group. It has all the features you're looking for, and the pro version can even import and export visio files.
There's also a website called Graffletopia (which, as a new user, I'm apparently not allowed to link to) that's full of user-contributed stencils and extras you can use.
I am a fan of OpenOffice Draw.
Anyway, This page discusses a few - http://www.osalt.com/visio
When I did my course at uni, we were encouraged to use Violet for UML modelling as a alternative to Visio, can't remember if it does what you need though!
(I am unable to find it, but sure this has been asked before.)
And then there's VUE, very powerful tool, best of all its free! you just have to sign up with your email an password to download the installation
The Visual Understanding Environment (VUE) is an Open Source project based at Tufts University. The VUE project is focused on creating flexible tools for managing and integrating digital resources in support of teaching, learning and research. VUE provides a flexible visual environment for structuring, presenting, and sharing digital information.
You need Java installed for it though
I just found out about yEd and am very happy with it.
I was looking for open-source or just freeware Visio alternatives for my home Windows box for years, unfortunately without avail. Every tool I tried (Dia, OpenOffice, Gliffy) was problematic in many ways, not to mention missing lots of advanced features from Visio.
At last this year I bit the bullet and bought Visio 2007 catching a sale that made it very reasonably priced. Now I'm not looking back - it's an amazing tool, well worth paying for.
A very brief google search would turn up a number of similar products and projects in open source and freeware. Probably the closest to what you are looking for would be dia
I have used Balsamiq - It is very easy to use web app and pretty fast. If you don't want to buy the version - there is an online version which can do the job if you want quick mock ups.
We used to use Omnigraffle at work, until we discovered Concept Draw.
It isn't free nor open-source, but for me it is a must have. And it runs Windows and Mac for the same price..
I don't know if it has your specific feature requests or not, but Gliffy is a nice online diagram web application that does lots of stuff.