[osg-users] Geometry of Generic 3D Surface from Collection of Points

[Sebastian Messerschmidt]

Hi Erik,

 From what I understand you have a function generating a z value for x,y 
pairs. So basically you simply have to sample your function in regular 
distances to get the triangle coordinates.
If you already have the sampled points without further information you 
need to use the delaunay triangulation. IIRC, If it is a function the 
folding should not be problem for the delaunay algorithm, so I don't 
know if Roberts comment might be misleading.

Cheers
Sebastian
> Thanks for the response Robert!
>
> So, does that mean that there is no way to do what I want without somehow determining the coordinates of every individual triangle? And there's not even any way to do a 3D tessellation to get such triangle coordinates? :'
>
>
> robertosfield wrote:
>> Hi Erik,
>>
>>
>> The OSG has the osgUtil::DelaunayTriangulator and the GLU based osgUtil::Tessellator can be used for tessellating meshes, but both utilize a 2D projection to a plan to work out the connectivity so aren't appropriate for meshes that will be folded.
>>
>>
>>
>> Robert.
>>
>>
>> On 17 August 2015 at 02:21, Erik Hensens < ()> wrote:
>>
>>> Hi everyone!
>>>
>>> I have a collection of Vec3 vertices that define the shape of a geometry that I'd like to create. Typically I would create the geometry by adding a primitive set of the POLYGON type, but what should I do if the vertices are not all in the same plane?
>>>
>>> I'm sure this is a very common task and that there's probably a simple way to achieve this. What is the best basic approach to creating such a geometry?
>>>
>>> Ideally I'd like to be able to do this without having to choose the individual triangles or quads that will make up the entire geometry. For example, if I wanted to model any generic three-dimensional surface and all I had was a large sample of points on the surface.
>>>
>>> In case I'm not doing a good job explaining what I need, I've attached an image - let's say I had many points on the surface of that shape and I need to make a geometry that depicts it. How would I do this?
>>>
>>> Thanks in advance for your help![/img]
>>>
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>>>
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