Visualization using AIS

Hi,

I am trying OCCT's visualization capabilities for the first time for a C++ based application on Mac OS Big Sur. I followed the user guide at https://dev.opencascade.org/doc/occt-7.5.0/overview/html/occt_user_guides__visualization.html#occt_visu_2

However, I was unable to get any visualization or display pop up after I run my code. Here is a snippet:

#include "iostream"
#include "STEPControl_Controller.hxx"
#include "V3d_Viewer.hxx"
#include "OpenGl_GraphicDriver.hxx"
#include "Block.h"
#include "Path.h"
#include "OCCUtils.h"
#include "FilesystemUtils.h"
#include "AIS_InteractiveContext.hxx"
#include "AIS_Shape.hxx"


void createBlockInDirectory(std::string directory){


Block block(length, width, height);
writeSTEP(block.getShape(), directory);

//display code begins
 Handle(Aspect_DisplayConnection) aDispConnection = new Aspect_DisplayConnection();
 Handle(OpenGl_GraphicDriver) aGraphicDriver = new OpenGl_GraphicDriver (aDispConnection);
 Handle(V3d_Viewer) aViewer = new V3d_Viewer (aGraphicDriver);
 aViewer->SetDefaultBackgroundColor (Quantity_NOC_DARKVIOLET);
 Handle(AIS_InteractiveContext) aContext = new AIS_InteractiveContext (aViewer);
 Handle(AIS_Shape) aShapePrs = new AIS_Shape (block.getShape()); // creation of the presentable object
 aShapePrs->SetColor(Quantity_NOC_RED);
 aContext->Activate(aShapePrs);
 aContext->Display (aShapePrs, AIS_Shaded, 0, true);

}

int main() {
[indent]
std::string directory = "whatever is the path";
createBlockInDirectory(directory);
}

The block gets created and the code runs without errors, but I don't see any visualization. In the project's CMAKE, I have only included OpenCASCADE libraries and include directories, nothing from OpenGL or VTK separately.

Any piece of advice will be helpful. Any links to full code examples implementing AIS based visualization will be useful as well!