Free editor for PDF documents. Complete editing of PDF documents is possible with PDFedit. You can change raw pdf objects (for advanced users) or use many gui functions. Functionality can be easily extended using a scripting language (ECMAScript).
Extensible vector graphics editor with Latex text support.
Ipe is an extensible drawing editor for creating figures in PDF and Postscript format. It supports making small figures for inclusion into LaTeX-documents as well as presentations in PDF.
Jade is a cross-platform diagram editor built on the Qt framework.
Jade is a cross-platform diagram editor built on the Qt framework. It is similar in scope to Microsoft Visio or Gnome dia. It is released under the GNU General Public License version 3.0 and is available for Windows, Linux, and likely any other platform that is supported by the Qt library.
Papyrus is a C++ scenegraph (canvas) library that uses cairo/cairomm for drawing operations. This allows papyrus to be used to draw in a Gtk+/Gtkmm widget, or draw to png, pdf and ps surfaces. In concept it is similar to the Gnome canvas or QT canvas.
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GeekCAD is a free open source CAD system. It's based on Qt4.
Features of this project:
1. dxf import, export;
2. raster bitmaps export;
3. native postscript or pdf export (in future);
4. Python scripting;
5. Parametric drawings.