Duplicate nurbs surface patches maya 2016 autodesk. Surface modeling 3ds max 2016 autodesk knowledge network. If the aim was to use flow along surface or orient on surface to apply the decoration then wed really need a surface rather than a polysurface. In surface modeling, you typically use the ribbon convert to poly command to. It is meant simply to be raw material for creating a nurbs model. While 3d modelling most people prefer using 4 point polygons as much as possible. You can convert a nurbs surface to a polygon mesh whether it was created in maya or imported from another 3d application. Instead, subdivision, because of its ability to handle arbitrary topology and ease of use, has become an attractive alternative to nurbs, especially for modelling in highend animation productions pixar, derose et al. Add a nurbs surface into your scene above or beside a meshed object of interest your ship hull when in object mode. The following sets of data is choosen for the nurbs vectors. Conversion of trimmed nurbs surfaces to catmullclark. Surface modeling is more freeform than geometric parametric modeling. Sectioning the mesh to create a series of polylines which.
The advantage of fitting with nurbs surfaces is well known, but it is also known that nurbs surfaces have several deficiencies. This is a perfect mesh to now directly feed into tsplines though, which can smooth out all kinks and convert to nurbs. U options for making the curve open or closed, and extending all the way to the endpoints or not. Nurbs are commonly used in computeraided design, manufacturing, and engineering and are part of. The initial surface you create using the create panel is a planar segment with points or cvs. Convert nurbs surfaces to a polygon mesh maya 2016. In the early 1970s, b or basis splines were created there are an infinite number of splines. If the nurbs surface has a texture applied to it, this texture is assigned to the new polygonal object. Nurbslines can use many of the same tools regular nurbs patches use such as the rectangle select tool, enabling us to scale, rotate, translate squash and stretch any region of the sketch just like we can with patches. Most of the mathematics behind the curve are similar to the surface.
The trimmed nurbs surface will be a degree 1 x 1 surface as with the quads, just with one half trimmed off to form a triangle. This plugin gives rhino the ability to reconstruct the geometry of an object from a mesh or point cloud which describes it. The shape of a nurbs surface is defined by a number of control points and the degree of that surface in the u and v directions. Tutorial 6 convert a mesh to multiple surfaces with trimmed surface. The nurbs to polygons action bakes the nurbs uv values onto the corresponding polygonal vertices.
And nomatter what it would have to be created of a very large amount of surface patches. I managed to convert a model to patch then nurbs, but its all triangulated and not smooth curves at all. It can deform surface primitives of any type or degree. Rhino nurbs use control points to define the shape of a curve. Nurbs surface objects are the basis of nurbs models. Create nurbs primitive plane change the u patches v patches 5. The more control points, the more detailed a curve. The subdivision representations have the great advantage that if two subdivision surfaces share a boundary edge in base meshes, they both contain exactly that. Nonuniform rational basis spline nurbs is an accurate mathematical representation of curves and surfaces. Working on a set of intersecting nurbs surfaces, nurbs fusion automatically eliminates the intersected parts and connects the remaining parts smoothly with auxiliary surfaces, so that a polysurface composed of multiple nicely joined nurbs patches is obtained. Lets first of all convert the subd surface to nurbs.
Nurbs are commonly used in computeraided design, manufacturing, and engineering and. Nonuniform rational basis spline nurbs is a mathematical model commonly used in computer graphics for generating and representing curves and surfaces. The following video shows how to create surface by using tpoint in curve network. Some sources say that a nurbs patch is a specific type of nurbs surface, while other sources say that patches and surfaces are the same thing. Tripatches are build with triangles, in order to get a most consistent polygon spreading. Some just give you more control over these shapes, such as products like maya and rhino.
It depends on your polysurface, and how the trims are oriented. The surface from patch will probably need to trimmed. Another program combination that overcomes many of the shape limitations of nurbs is the autodesk tsplines plugin for rhino, which allows three, four, or multiplesided patches to be modeled. Concepts a patch is a surface made from spline curves one spline goes in one direction, called the u direction a second spline goes in another direction called the v direction together they form a grid, or mesh, of curves. To duplicate surface patches select the patch or patches. A polygon is a flat 3d surface created by a 3 or more points. You can then manually merge patches into larger single surfaces. Select the nurb surface and go into edit mode, then subdivide as needed to get a suitable resolution for your needs, and perhaps scaling so that the nurbs surface would fully cover your mesh when shrink wrapped. What is a polygon, mesh, patch, and nurbs in 3ds max. Extracting points from the vertices of the mesh, and then using patch to create a surface from the points. First, need the boat to be a nurbs model for me to modify the entire object and to add more from it since the original model is from our client who wants us to modify and manufacture his design.
This method is powerful but extremely limited in scope. Polyworksmodeler offers an intuitive surfacing approach in which curves are first laid down on a polygonal model, and then automatically intersected to form. Video introduction to quadremesh in rhino3d v7 wip from. Nurbs, or nonuniform rational b splines, are what most 3d modelling applications use to produce freeform shapes. Modelling techniquesdifferences between nurbs and polygon. One of the big advantages of using nurbs lines over a pencil is the lines can be easily modified without needing an eraser.
Again, im perfect fine with quite some loss in accuracy. The transition between any two nurbs surface patches reaches g1 continuity. These fit points can be used to manipulate the geometry. It has a tendency to freeze your computer if you are trying to convert a large mesh into nurbs. Though making little simple untrimmed nurbs surfaces out of these worked, there was much worse subtle little kinks between faces than my large patches showed, which was already a hassle. A starting surface may be needed to obtain a satisfactory surface with patch. Although, nurbs patches must be four sided, which can be a hinderance without proper planning, on the other hand you can use curves to create surfaces. But for final rendering, a polygon is always converted into 3 point polygons. A nurbs 2d surface is, to place it simply, a 2d derivative of the 1d curve.
Working with nurbs surfaces and surface tools in autocad. Gl provides subroutines that draw parametric nonuniform rational bspline surfaces nurbs that can be trimmed with nurbs curves and piecewise linear curves as you can with most other graphics library primitives, you can transform nurbs curves and surfaces with the standard gl modeling commands. Modeling with non uniform rational b splines nurbs surfaces has become a standard in cadcam systems due to its stability, flexibility, and local modification properties. Nurbs are great for creating organic surfaces and for industrial design. Polysurface to single surface grasshopper mcneel forum. Tutorial 4 convert a mesh to multiple surfaces with quad face. While there are other modelers that can do this, one key difference is that tsplines can accurately convert the tsplines model into nurbs surfaces for. At some point, rhino will convert a subd object to as few as possible nurbs patches but that technology is in progress as we speak.
Advanced rhino nurbs to mesh reduce mesh mesh to polysurface duration. Based on the above, the resulting polysurface from meshtonurb will have exactly the same edges as the original mesh model and be composed entirely of degree 1 x 1 bilinear nurbs surfaces. Hosted by one of our application specialists, this shows how to use nsided patches in polyworksr imedittm to simplify creation of and to improve the fit of nurbs patches. You can think of nurbs surfaces as a grid of nurbs curves that go in two directions. It offers great flexibility and precision for handling both analytic surfaces defined by common mathematical formulae and modeled shapes. Nurbs stands for nonuniform rational bspline curves. Using quadrangles, the polygon mesh would converge to one corner, what may cause ugly creases. The surface fusion algorithm performs in three steps. Triangle surfaces will be planar and trimmed or not according to the option chosen. Nurbs surfaces are ideal to mathematically describe freeform surfaces, plus they are cadcam friendly. In parametric modeling, you create a primitive such as a sphere or a plane from the create panel, and then use the existing settings parameters to change dimensions, segments, and so on.
Read the help section for patch and experiment with the settings. Rhinoresurf for rhino can drape a surface over a point cloud with specified tolerance. They are equations used to define curves or surfaces that simulate the designers batten in terms of stiffness and continuity. Once you have created the initial surface, you can modify it on the modify panel by moving cvs or nurbs points, attaching other objects, creating subobjects, and so on. Now a splinepatch can be created also from three splines. Or if the trim lines were on or very close to isolines, then you could maybe tweak them to.
You can convert a nurbs surface to a polygon mesh whether it was created in maya lt or imported from another 3d application. Id like to automatically programmatically, could be with some parameter tunings divide the mesh into a few patches and then fit it. Create a single surface which is similar to the shape of the mesh. Start a new document, delete the default cube, blablabla, but stay in object mode. Conversion of fine organic surface mesh to a few patches. This gives a polysurface with a surface patch for every subd face.
Note that one thing id like to avoid is to convert an stl of 10,000 triangles to a nurbs with 10,000 patches. The tesselation tool takes all nurbs patches and nurbs patch providing objects from the selection. In the caatopnurbssurfmultipatch sample, a multi patch 4 nodes along u and 3 nodes along v nurbs is to be created. A nurbs surface cannot be fitted over an unorganized and scattered set of points and. If the surfaces were all untrimmed then you could use the isolines to make a mesh relatively easily. Resurf rhinoresurf, unfold mesh, mesh to nurbs, point. The result is that a whole range of curve tools are also applicable to the surface, taking in account that it has an extra dimension. Switch to edit mode, and find the surface context in the properties window for nurbs curves, you previously had the cyclic. The knot vectors do not have the 2 superfluous knots at the start and end of the knot vector. In autocad, you can treat a nurbs surface as a 3d spline with fit points. Using patch to map a terrain with a point cloud youtube. Sectioning the mesh at a number of locations, typically using contour although sometimes section is used. This plugin gives rhino the ability to reconstruct the geometry represented by nurb surface of an object from a mesh or point cloud which describes it.
In this paper, we propose a new nurbs modeling technique, called nurbs fusion and present a complete algorithm for nurbs fusion. Rhinoresurf for rhino can automatically generate nurbs surfaces from a selected mesh. How to create a single nurb surface from a mesh polysurface. As of now, if you own rhino 6, you can use quadremesh to convert your mesh or brep to a subd object. Also, the result may be a polysurface instead of one single surface. There are other ways to convert back to nrubs including a single surface but it depends on your geometry and level of accuracy you desire. Trimmed surfaces are also converted in the process. The shape of the surface is defined by a number of control points and the degree of that surface in each one of the two directions u and vdirections.