Eagle NurbsWhat is Eagle Nurbs?

Merlin the standard Solids Modeling (SM) technology integrated in Eagle has proved powerful and precise enough for many applications. Merlin SM as a facetted representation has obvious limitations, particularly in terms of precision, storage usage and speed, especially when the shape or shell required is rather complex. In Macrovision we recognize that using NURBS curves and surfaces is sometimes a necessary part of graphics application development particularly in the CAX field of engineering. We already have had experience of integrating NURBS technologies as part of previous OEM bespoke development but needed to find a more flexible solution to meet Eagle developer needs. The resulting implementation of NURBS in the Eagle Framework is commonly known as EagleNURBS or the Exact Geometry Module.

Nurbs Implementation

NURBS is implemented in Eagle using a Software Abstraction Layer (SAL) which provides an intermediate software layer to facilitate swapping of NURBS libraries. Eagle NURBS EG release currently integrates OCC a well known engine for NURBS geometry but this can be unplugged and Eagle Nurbsreplaced with libraries of choice such as ACIS or SMLib. The beauty of this realization is that the Eagle programmer developments are shielded from the complexity of underlying technology.

Interaction with NURBS geometric engine is completely embedded in the Eagle framework. NURBS entities like curves, profiles, surfaces, shell and bodies, co-exist with Eagle geometry such as lines, pipes, faces, Ufos (Merlin SM Objects) and all the other standard Eagle entities. Eagle determines which geometry it has to deal with depending on the function issued and the type of item involved, then switches to the appropriate geometric engine in a completely transparent manner.   

NURBS geometry is native to the environment and therefore all the functions of the framework such as display, editing and calculation are available. Display for example can be achieved in either Eagle graphics or OpenGL modes and all of the functionality of these features are exposed.

NURBS geometry stored in IGES files or in OCC-BREP files can be imported  and are then embedded in the Eagle model file.  Native embedding of IGES file handling is a powerful feature for Eagle, since IGES files are used natively by thousands of applications and millions of users.  This capability  opens the door for transparent integration of application data between systems using the format.



  • Object orientated graphics development
  • Develop for real world precision and accuracy
  • Creation of profiles from basic items
  • Curve and surface creation
  • Projection of a curve on a surface
  • Shell creation
  • Full range of calculation options
  • Harness all existing display methods
  • Calculation of geometrical intersections
  • Import and export IGES files
  • Accelerated time to market
  • Develop leading edge graphics solutions
  • Cost effective code reuse
  • Robust reliable proven core technology
  • Lower implementation costs
  • Lessen dependency on highest skilled coders
  • Integrate your existing developments
  • Easier to embrace changes in technology


Eagle NURBS is delivered with Eagle 14 and requires a EG license. An Extended LibEagle API to handle interaction with Eagle native files containing NURBS objects.


If you are an ISV (Independent Software Vendor), Enterprise Developer, Equipment Manufacturer or Educator and want to develop or integrate leading edge 2D/3D graphics in your application using world class software Eagle CDS is the right choice. Already used in a wide variety of industries providing cost and time saving benefits Eagle and Python allow the developer to simply get on with the job of providing the solution.


Code Reuse and Productivity Maximized

In an effort to reduce coding many of the standard Eagle functions maintain the same syntax and functionality in EagleNURBS implementation. Some functions have been enhanced with new options, while others required to de with new entities such as Curve, Interpolate and Projection functions are completely new. This means for developer already using Eagle SM the transition is lessened. Even if developing an application from the ground up Eagle considerably reduces the task of implementing NURBS in your graphics application especially if set against having to do all the implementation work yourself.

Eagle NURBS offers to the Eagle Graphics Framework developer an increased precision in the development graphics applications that accurately reflect the physical domain. NURBS is essential in market segments such as ship design, aviation, motor, wind turbines and container design for commodity items.

In a way Eagle NURBS demystifies some of the complexity involved in developing graphics applications requiring NURBS functionality. This is one of the core principle of Eagle framework to provide a layer of abstraction from the inner workings of the graphics programming task therefore allowing the developer to concentrate on the solution provision. Using Eagle you are safe in the knowledge that even if your application requires changes in the underlying technology this can be achieved at significantly less cost that having to design from the ground up.