Will TCavnas::Clear() release the memory of everything on it?

Dear experts

Do I need to manually delete pointers of objects that already Drawn on a TCanvas after I call TCanvas::Clear()? e.g.:

TCanvas*c = new TCanvas();
TGraph* g = new TGraph();
TMarker* m = new Marker(1,1,22);

//Do I need to do this?
//delete g;
//delete m;

Try to draw them after c->Clear() and see (note that you need to add at least 1 point to the graph in the first place).

Seems the sub-pads will be deleted but everything drawn on the pads will not.

When you create a graphics object, it exists independently. Drawing it does not transfer its ownership to the canvas/pad. You need to delete it if you want to free the associated memory.