Examples > Primitives

Points.

Let's create an array of the points lying on a paraboloid.

The intervals of changing the coordinates will be:

X lies in the interval of [-15, 15]

Y lies in the interval of [-15, 15]

The step of changing X and Y coordinates will be 1.

The paraboloid equation will be of the following type:

Z = 0.05*X*X+0.03*Y*Y;

Let's calculate the color and thickness of the point depending on the Z coordinate on the following formulas:

point color number from palette = residue of division Z by 100

point thickness = residue of division Z by 3 + 1;

So, the function of creating the necessary points array will look like this:

for (int i=-15;i<15;i++)

{

for (int j=-15;j<15;j++)

{

double pZ = 0.05*i*i+0.03*j*j;

sgCPoint* pnt = sgCreatePoint(i, j, pZ);

sgGetScene()->AttachObject(pnt);

pnt->SetAttribute(SG_OA_COLOR,((int)pZ)%100);

pnt->SetAttribute(SG_OA_LINE_THICKNESS, ((int)pZ)%3+1);

}