Graphs are not drawn (and actually should not be)

[AlexisDrogoul]

Describe the bug
Many different types of objects can be drawn in GAMA, but nothing is implemented to draw graphs. However, the use of draw with objects of type graph exists in some places, for instance Topology.experiment in Spatial Tests.

To Reproduce
Steps to reproduce the behavior:
Open Topology.experiment. Remove all the grid and species layers in the displays.

experiment visu type: gui {
	output {
		display map4 {
			//grid cell4 border:#grey;
			//species dummy;
			graphics the_graph {
				draw c_graph4 color:#black;
			}
		}	
		display map6 {
			//grid cell6 border:#grey;
			graphics the_graph {
				draw c_graph6 color:#black;
			}
		}
		display map8 {
			//grid cell8 border:#grey;
			graphics the_graph {
				draw c_graph8 color:#black;
			}
		}
	}	
}

Open the experiment named visu. Nothing appears on screen.

Expected behavior
That either the graphs is drawn if it is spatial or that an error is raised to tell that graphs can't be drawn.

Desktop (please complete the following information):

• OS: macOS Sonoma
• PC Model: MBP Pro 16" M1
• GAMA version: all

[chapuisk]

I would have been in favor of drawing the graph rather than raising an exception, but if it is the expected behavior for this fix, it does what it meant to do !