knot points and control points in NURBS

Hi

I am writing a program where I am required to display NURBs surfaces. The input data were at least 280,000 vertices of a model. Each vertex makes up of x, y, z coordinates. Each coordinate is float data.

Each vertex represents a point of a 3-D rectangular block (like that of a Lego block), i.e. there are at least 280,000 blocks in the model. Each block should have 8 vertices to define the 8 end-points of the blocks, but the input file only specify one of the 8 vertices of each blocks.

It is the requirement that the program cannot use cubes or boxes to display the model. The model must be rendered using NURBS as the model is similar to a terrain.

if can provide some information on how to determine the knot points and control points required in openGL GLU NURBS, from the input data, many grateful thanks in advance.

Make up your mind. Does the file specify
blocks or NURBS control data? You’re saying
it represents blocks, but then you say it
has to be rendered as NURBS. There’s too
little information about the problem to give
any kind of answer to that.

Hi

the file specify blocks, but the requirements of the program is that the data must be rendered using NURBS.

I am thinking of how to get the array of knot points and control points from the vertices of the blocks. many grateful thanks in advance.

Hi

the requirements of the program means that I am required to write a program which reads in the input file and display the terrain from the data specified in the input file.

The input file specifies 28,000 vertices, each representing one block, total 28,000 blocks.
The input file specifies the length, height and breadth of the blocks.
Each 3D block should have 8 vertices, and we can generate the other 7 vertices of each block by making use of the length, height and breadth and the vertex specified in the input file.

The input file specifies the above information. The assignment is to write a program to read in the above input file and render the terrain image.
One of the assignment rules is that, we cannot just render the image as blocks. We must render the image making use of NURBS. Though the input file specifies one of the vertices of each of the 28,00 blocks and the length, breadth and eight of each block, we must try to think of a way of how render the image using NURBS.

many grateful thanks in advance.