Development

Advanced Geospatial Solutions
Offers technology to display and manipulate 3D CAD and terrain models, designed to be embedded into GIS, CAD, technical documentation and e-learning applications.
http://www.advancedgeospatial.com/

Building Block Software
Provides no-cost C library source code for 2D and 3D geometry operations, boundary offset, area booleans, milling and turning toolpaths.
http://www.buildingblock.com/

Cadmai Software GmbH
Cadmai ist a parametric and relational CAD module that can be integrated as a intelligent viewer in other applications.
http://www.cadmai.com/

Calligraphic Interface for Tridimensional Surface Modeling
An educational project trying to develop a gesture-based interface for 3D modeling. It uses wxWindows, ACIS, OpenGL and DevIL.
http://virtual.inesc.pt/~tfdc

Component Ingenuity, Inc.
DWGDOMlib and DXFDOMlib modules for reading and manipulating DWG and DXF files from within .NET applications.
http://www.componentingenuity.com/

CurveTrainer
A basic experimental lab for geometric shape processing, for learning about the mathematical theory and practical manipulation of various parametric curves.
http://www.pml.co.jp/cvt/index.html

C4W
Offers modelling kernel libraries and related tools for construction, analysis, and presentation of 3D models.
http://www.c4w.com/

D-Cubed
Supplies geometric constraint managers, hidden line and collision detection components to the CAD/CAM industry.
http://www.plm.automation.siemens.com/en_us/products/open/d-cubed/index.shtml

DeveloCAD.com
Graphics libraries for Delphi developers, such as an OpenGL canvas, hidden lines algorithms, and geometry data management.
http://www.develocad.com/

DInsight
KernelCAD is an embedded CAD software, which adds interactive 3D solid modeling functionality to any Windows application.
http://www.dynoinsight.com/

Gardos Software
Avax ActiveX control to view, create, edit, print, and manage 2D vector drawings.
http://business.hol.gr/gardos/

Geometric Software Solutions
Technology provider to CAD/CAM/CAE vendors, offering components for geometry manipulation, information management, and collaborative engineering.
http://www.geometricsoftware.com/

Geometry Handling Library
A library for 2-D and 3-D geometric calculation in C, with functions for shape generation, geometric evaluation, intersection, and offsetting and filleting.
http://www.pml.co.jp/ghl/index.html

IntegrityWare, Inc.
Offers libraries for geometric solvers, trimmed surfaces, and polygon optimization, including visualization features.
http://www.integrityware.com/

KolbaSoft
The VeCAD 2D vector graphics library can be used to create CAD applications.
http://www.kolba.com/

Kotem Technologies Inc.
Offers components for CAD/CAM software, such as the 3D Core CAD-engine, the SmartFit 3D best-fitting application, and related functionality.
http://www.kotem.com/

LEDAS Ltd.
Provides a variational geometric solver for CAD, scheduling, planning and other intellectual solutions, using proprietary constraint-based technologies.
http://ledas.com/

Open CASCADE
A 3D modeling kernel that consists of reusable C++ object libraries that are available as Open Source.
http://www.opencascade.com/

Soft Gold, Ltd.
AutoCAD DXF tools for developers. ABViewer for Windows Commander and Far Manager. 3d DXF viewing and printing with C++, VB, and Delphi.
http://www.cadsofttools.com/

Spatial Technologies, Inc.
Develops, markets and supports software components for 3D modeling, visualization, and interoperability, such as the ACIS solid modelling kernel.
http://www.spatial.com/

VectorDraw Drawing Components
Object oriented 2D/3D graphics libraries with AutoCAD file format support, as well as a web-based version.
http://www.vdraw.com/

Weresc
Offers CADE, a CAD ActiveX control to view and edit 2D vector graphic, with web and DXF support.
http://www.weresc.com/

Wout Ware
CadLib is A .NET DXF file manipulation library with 2D and 3D support that also handles export to image formats and PDF.
http://www.woutware.com/