@Override
	protected Color getDefaultVertexShapeColor() {

		if (isInDirection() && tooManyIncomingReferences) {
			return TOO_BIG_VERTEX_SHAPE_COLOR;
		}

		if (isOutDirection() && tooManyOutgoingReferences) {
			return TOO_BIG_VERTEX_SHAPE_COLOR;
		}

		return DEFAULT_VERTEX_SHAPE_COLOR;
	}
A vertex shape provider for the {@link FunctionCallGraphPlugin}.
Ghidra/Features/GraphFunctionCalls/src/main/java/functioncalls/graph/FcgVertexShapeProvider.java