% prepare figure and axis
hFig = figure('menu','none', 'DoubleBuffer','on');
hAx = axes('Parent',hFig, 'XLim',[0 1], 'YLim',[0 1], 'Box','on', ...
	'XLimMode','manual', 'YLimMode','manual');
axis(hAx, 'equal', 'square')

% points and text
hLine = line('XData',[], 'YData',[], 'LineStyle','none', 'Marker','.', 'Color','b', 'MarkerSize',1);
hTxt = text(0.8,0.9, '0', 'HorizontalAlignment','center', 'BackgroundColor','w');

% draw circle arc
theta = linspace(0,pi/2,100);
hCircle = line(cos(theta), sin(theta), 'Color','r', 'LineWidth',4);
%uistack(hCircle,'top')

% incrementally increase number of points drawn
X = rand(1e5,2);
N = round(linspace(1,size(X,1),200));
for i=1:numel(N)
	% update points
	set(hLine, 'XData',X(1:N(i),1), 'YData',X(1:N(i),2))
	
	% update pi approximation text
	piApprox = 4*( sum(sum(X(1:N(i),:).^2,2)<=1) ./ N(i) );
	set(hTxt, 'String',sprintf('%.8f',piApprox))
	
	% refresh
	drawnow
	if ~ishandle(hFig), break; end
end