How to sample implicit function in different bounds

Support
1

I get a vtkImplicitFunction object and want to sample it over a structured point set. I know the approximate shape of the implicit. So I want to sample vtkImplicitFunction in different bounds(they could be overlap) and finally put them together

// this is the implicit function
vtkSmartPointer<vtkImplicitFunction> implicit = xxx;
// sample it in different bounds(overlap)
for(int i = 0; i < n; i++){
    auto sample = vtkSmartPointer<vtkSampleFunction>::New();
    sample->SetImplicitFunction(implicit);
    // bound_i 
    sample->SetModelBounds(bound_i);
    sample->update();
}
// put each sample in a image data, how ?
vtkSmartPointer<vtkImageData> data = sum(samples)

auto surface = vtkSmartPointer<vtkContourFilter>::New();
surface->SetInputConnection(data);
surface->ComputeNormalsOff();
surface->SetValue(0, 0.0);
surface->Update();

How can I do that?