Qwtplot3D : plot 3D polyline

[franchouze]

Hi everybody,

I am using Qwtplot3D 0.2.7 to plot 3D surface and it works fine.

On my own inherited class of SurfacePlot, I also need to plot a 3D polyline.
The only way I found to draw something is to overload the createData() function like this :



void PlotSurface::createData()
{
Qwt3D::SurfacePlot::createData();
if(!ptrIsNul(_myData))
{
Qwt3D::setDeviceLineWidth( 2 );
glColor3d(0., 1., 1.);


glPushMatrix();
glScaled(_scaleX,_scaleY,_scaleZ);
glTranslated(_offsetX,_offsetY, _offsetZ);
glRotated(_angleZ,0.0,0.0,1.0);

glBegin( GL_LINES );



for(unsigned int i = 0; i < _myData->getNbLines(); i ++)
{
for(unsigned int j =0; j < _myData->getLine(i)->getNbPoints()-1; j++ )
{
Point<float,3> p1 = _myData->getLine(i)->getPoint(j);
Point<float,3> p2 = _myData->getLine(i)->getPoint(j+1);
glVertex3d(p1[0], p1[1], p1[2]);
glVertex3d(p2[0], p2[1], p2[2]);
}
}

glEnd();
glPopMatrix();

}
}


1) Is it the good way to do it ?

2) The lines are drawn. However, when I look the surface plot from above (I then see a X,Y plane), the lines are not at the correct coordinates. Moreover these coordinates depends on the Z values of my surface data. The _offsetX etc... parameters are set to 0 ans _scaleX etc... are set to 1.0. _angleZ is also equal to 0.0.
I would like to draw those lines like the grid of the surface is drawn but I can't find a way.

Any Idea ?

Thanks in advance.