T-Splines 2.0 overview video

Watch this video to see how T-Splines allows you to create smooth organic designs, edit them quickly, and export your models for manufacturing without remodeling.



A higher resolution video can be found on Vimeo

T-Splines in architecture

Last year, HOK used T-Splines for these architecture concepts. The project was not built, and they recently gave permission for us to share the images on our site.

Nearly 1/3 of all T-Splines licenses are sold into architecture. If you are an architect, how are you using T-Splines? (Or how would you like to use T-Splines?)

Polygonal Modeling and T-Splines

In 3D computer graphics, polygonal modeling is an approach for modeling objects by representing their surfaces using polygons. The basic object used in polygonal modeling is a vertex, a point in three dimensional space. Two vertices connected by a straight line become an edge. Three vertices, connected to the each other by three edges, define a triangle, which is the simplest polygon. Four sided polygons (generally referred to as quads) and triangles are the most common shapes used in polygonal modeling. A group of polygons which are connected together by shared vertices is referred to as a mesh. As shown in the figure below, meshes are comprised of flat, faceted faces.










T-spline surfaces can be viewed as meshes or as smooth surfaces. The following is an example of a T-spline displayed as a mesh and as a smooth surface.

It is possible to construct a mesh in many ways; two common techniques include basic polygonal modeling, and a popular subset of polygonal modeling called box modeling.

Basic polygonal modeling techniques center on placing individual vertices. Operations like adding polygons, subdividing faces, extruding segments and merging edges are common in polygonal modeling.

Box modeling (also known as subdivision modeling) starts with a simple box, and then modifies the box using extrusion to gradually add detail to the model. The final surface is a smoothed version of the box model.


Box modeling and basic polygonal modeling are not independent from each other and are often used together on the same model. While box modeling can be easier and faster to use, polygonal modeling is more versatile and allows for more detailed modeling and shape control. A design process that uses both these approaches can be adapted to many particular modeling situations.

How T-Splines modeling differ from other polygonal modeling methods

The T-Splines plugin brings polygonal and box modeling capabilities to Rhino and allows them to be integrated with NURBS techniques. Additionally, T-Splines enhances traditional polygonal modeling workflows by introducing T-Points to create local areas of detail.

T-Splines is the only modeler that combines NURBS and polygonal modeling methods together in a single workflow.

The Technology of T-Splines

What is the magic underneath the covers that makes T-Splines such a unique and compelling new technology? How does T-Splines overcome limitations that are inherent to existing NURBS and subdivision based modeling approaches? Four key components of the patented T-Splines technology make it all possible:

T-Points

A non-uniform rational b-spline Surface or NURBS surface is defined by a set of control points which lie, topologically, in a rectangular grid. This means that, in practice, a large percentage of NURBS control points are superfluous in that they contain no significant geometric information, but merely are needed to satisfy the topological constraint.

In the frog model below, 55% of the NURBS control points are superfluous.

In contrast, a T-Spline’s control grid is allowed to have partial rows of control points. A partial row of control points terminates in a T-Point, hence the name T-Splines. In the T-Splines frog, the red control points are T-Points.

The NURBS model of the frog has 11,625 control points. The geometrically identical T-Splines frog has only 5,035 control points, over 56% fewer, resulting in a more light weight and more easily editable representation.

Minimizing control points makes it easier to create models, control surface smoothness, decrease file size, and speed up editing time.


Local detail

As a direct result of the ability to create partial rows of control points within a single surface, the user can now create a surface with varying level of detail only where required.

Refinement, the process of adding new control points to a control mesh without changing the surface, is an important basic operation used by designers. A limitation of NURBS is that refinement requires the insertion of an entire row of control points, increasing the density of the mesh across the entire surface. T-Points enable T-Splines to be locally refineable. As shown below, a single control point can be added to a T-Splines control grid.


Support for local detail in a single surface makes it easier to model complex shapes and create smooth watertight models.

Non-rectangular surfaces with star points

With T-Splines, non-rectangular surfaces can be constructed using star points, also called poles or extraordinary points. This overcomes another fundamental NURBS limitation: In NURBS surface modeling, constructing a complex shape with varying detail, curvature or smoothness requires many individual rectangular patches. Maintaining continuity and smoothness across these patch surfaces is a significant challenge.



Star points also enable modeling techniques such as extrusion, face deletion, and merging of surfaces that greatly increase design freedom for the user. Star points are used today in subdivision surface modeling, which is popular in animation, but T-Splines introduces them to industrial design in a NURBS-compatible format for the first time.

100% compatibility to NURBS

All T-Splines surfaces are 100% compatible with NURBS and create gap-free, smooth and manufacturable surfaces. T-Splines surfaces can be converted to untrimmed NURBS surfaces, and vice-versa, without any loss or change to the surface shape.

T-Splines provides a far more efficient conversion of designs to NURBS than converting directly from subdivision or polygonal modelers. T-Splines bridges gaps between popular polygonal modeling capabilities and traditional NURBS modeling.


T-Splines easily integrates into existing design processes and workflows, with seamless transfer of designs to engineering and manufacturing.

"The T-Spline technology addresses some important limitations that are inherent in conventional NURBS surfaces. T-Splines are based on solid mathematical principles. An important practical consideration is that T-Splines are forward and backward compatible with NURBS. "
--Dr. Rich Riesenfeld, Founder of B-splines in CAD

Learn more

Does this sound too good to be true? Read some of the reviews from experts in the industry, check out our gallery of T-Splines models, or try a free evaluation of our certified Rhino or Maya plugins.

If you are interested in the technology, T-Splines is also available in the T-Tools software development kit for companies that want to leverage the power and capabilities of T-Splines within their own application.

T-Splines 2.0 for Rhino Beta Released

T-Splines, Inc., creators of precise and flexible 3D surface modeling tools with full industry standard compatibility, today announced the beta release of T-Splines 2.0 for Rhino.

The 2.0 version adds several new tools and workflows to generate free-form surfaces and brings a full suite of polygonal modeling techniques into Rhino. T-Splines can be used to create an entire model, or they can be used to add organic components to Rhino models. T-Splines gives Rhino users a way of exploring shapes easily and quickly in an intuitive way, and helps designers shorten the time between imagination and building 3D models. A video overview of the new product can be found at Vimeo.

Introducing the T-Splines Blog

Hello and welcome to the new T-Splines blog. As we get ready to launch a major new milestone release, we wanted to provide new means to broaden and extend the conversation about T-Splines. We hope that this blog will provide you with an easy means for keeping up to date with the latest T-Splines news and stories.

Over the next month we will highlight the new features of T-Splines for Rhino 2.0, and we will also feature some guest authors and customer stories.

We want to be sure that this blog provides you with the information you want, so please let us know what you would like to see featured here.