function [varargout] = myaa(varargin)
%MYAA Render figure with anti-aliasing.
% MYAA
% Anti-aliased rendering of the current figure. This makes graphics look
% a lot better than in a standard matlab figure, which is useful for
% publishing results on the web or to better see the fine details in a
% complex and cluttered plot. Some simple keyboard commands allow
% the user to set the rendering quality interactively, zoom in/out and
% re-render when needed.
%
% Usage:
% myaa: Renders an anti-aliased version of the current figure.
%
% myaa(K): Sets the supersampling factor to K. Using a
% higher K yields better rendering but takes longer time. If K is
% omitted, it defaults to 4. It may be useful to run e.g. myaa(2) to
% make a low-quality rendering as a first try, because it is a lot
% faster than the default.
%
% myaa([K D]): Sets supersampling factor to K but downsamples the
% image by a factor of D. If D is larger than K, the rendered image
% will be smaller than the original. If D is smaller than K, the
% rendering will be bigger.
%
% myaa('publish'): An experimental parameter, useful for publishing
% matlab programs (see example 3). Beware, it kills the current figure.
%
% Interactivity:
% The anti-aliased figure can be updated with the following keyboard
% commands:
%
% <space> Re-render image (to reflect changes in the figure)
% + Zoom in (decrease downsampling factor)
% - Zoom out (increase downsampling factor)
% 1 ... 9 Change supersampling and downsampling factor to ...
% q Quit, i.e. close the anti-aliased figure
%
% Myaa can also be called with up to 3 parameters.
% FIG = MYAA(K,AAMETHOD,FIGMODE)
% Parameters and output:
% K Subsampling factor. If a vector is specified, [K D], then
% the second element will describe the downsampling factor.
% Default is K = 4 and D = 4.
% AAMETHOD Downsampling method. Normally this is chosen automatically.
% 'standard': convolution based filtering and downsampling
% 'imresize': downsampling using the imresize command from
% the image toolbox.
% 'noshrink': used internally
% FIGMODE Display mode
% 'figure': the normal mode, a new figure is created
% 'update': internally used for interactive sessions
% 'publish': used internally
% FIG A handle to the new anti-aliased figure
%
% Example 1:
% spharm2;
% myaa;
% % Press '1', '2' or '4' and try '+' and '-'
% % Press 'r' or <space> to update the anti-aliased rendering, e.g.
% % after rotating the 3-D object in the original figure.
%
% Example 2:
% line(randn(2500,2)',randn(2500,2)','color','black','linewidth',0.01)
% myaa(8);
%
% Example 3:
% xpklein;
% myaa(2,'standard');
%
% Example 3:
% Put the following in test.m
% %% My test publish
% % Testing to publish some anti-aliased images
% %
% spharm2; % Produce some nice graphics
% myaa('publish'); % Render an anti-aliased version
%
% Then run:
% publish test.m;
% showdemo test;
%
%
% BUGS:
% Dotted and dashed lines in plots are not rendered correctly. This is
% probably due to a bug in Matlab and it will hopefully be fixed in a
% future version.
% The OpenGL renderer does not always manage to render an image large
% enough. Try the zbuffer renderer if you have problems or decrease the
% K factor. You can set the current renderer to zbuffer by running e.g.
% set(gcf,'renderer','zbuffer').
%
% See also PUBLISH, PRINT
%
% Version 1.1, 2008-08-21
% Version 1.0, 2008-08-05
%
% Author: Anders Brun
% anders@cb.uu.se
%
%% Force drawing of graphics
drawnow;
%% Find out about the current DPI...
screen_DPI = get(0,'ScreenPixelsPerInch');
%% Determine the best choice of convolver.
% If IPPL is available, imfilter is much faster. Otherwise it does not
% matter too much.
try
if ippl()
myconv = @imfilter;
else
myconv = @conv2;
end
catch
myconv = @conv2;
end
%% Set default options and interpret arguments
if isempty(varargin)
self.K = [4 4];
try
imfilter(zeros(2,2),zeros(2,2));
self.aamethod = 'imresize';
catch
self.aamethod = 'standard';
end
self.figmode = 'figure';
elseif strcmp(varargin{1},'publish')
self.K = [4 4];
self.aamethod = 'noshrink';
self.figmode = 'publish';
elseif strcmp(varargin{1},'update')
self = get(gcf,'UserData');
figure(self.source_fig);
drawnow;
self.figmode = 'update';
elseif strcmp(varargin{1},'lazyupdate')
self = get(gcf,'UserData');
self.figmode = 'lazyupdate';
elseif length(varargin) == 1
self.K = varargin{1};
if length(self.K) == 1
self.K = [self.K self.K];
end
if self.K(1) > 16
error('To avoid excessive use of memory, K has been limited to max 16. Change the code to fix this on your own risk.');
end
try
imfilter(zeros(2,2),zeros(2,2));
self.aamethod = 'imresize';
catch
self.aamethod = 'standard';
end
self.figmode = 'figure';
elseif length(varargin) == 2
self.K = varargin{1};
self.aamethod = varargin{2};
self.figmode = 'figure';
elseif length(varargin) == 3
self.K = varargin{1};
self.aamethod = varargin{2};
self.figmode = varargin{3};
if strcmp(self.figmode,'publish') && ~strcmp(varargin{2},'noshrink')
printf('\nThe AAMETHOD was not set to ''noshrink'': Fixed.\n\n');
self.aamethod = 'noshrink';
end
else
error('Wrong syntax, run: help myaa');
end
if length(self.K) == 1
self.K = [self.K self.K];
end
%% Capture current figure in high resolution
if ~strcmp(self.figmode,'lazyupdate');
tempfile = 'myaa_temp_screendump.png';
self.source_fig = gcf;
current_paperpositionmode = get(self.source_fig,'PaperPositionMode');
current_inverthardcopy = get(self.source_fig,'InvertHardcopy');
set(self.source_fig,'PaperPositionMode','auto');
set(self.source_fig,'InvertHardcopy','off');
print(self.source_fig,['-r',num2str(screen_DPI*self.K(1))], '-dpng', tempfile);
set(self.source_fig,'InvertHardcopy',current_inverthardcopy);
set(self.source_fig,'PaperPositionMode',current_paperpositionmode);
self.raw_hires = imread(tempfile);
delete(tempfile);
end
%% Start filtering to remove aliasing
w = warning;
warning off;
if strcmp(self.aamethod,'standard') || strcmp(self.aamethod,'noshrink')
% Subsample hires figure image with standard anti-aliasing using a
% butterworth filter
kk = lpfilter(self.K(2)*3,self.K(2)*0.9,2);
mm = myconv(ones(size(self.raw_hires(:,:,1))),kk,'same');
a1 = max(min(myconv(single(self.raw_hires(:,:,1))/(256),kk,'same'),1),0)./mm;
a2 = max(min(myconv(single(self.raw_hires(:,:,2))/(256),kk,'same'),1),0)./mm;
a3 = max(min(myconv(single(self.raw_hires(:,:,3))/(256),kk,'same'),1),0)./mm;
if strcmp(self.aamethod,'standard')
if abs(1-self.K(2)) > 0.001
raw_lowres = double(cat(3,a1(2:self.K(2):end,2:self.K(2):end),a2(2:self.K(2):end,2:self.K(2):end),a3(2:self.K(2):end,2:self.K(2):end)));
else
raw_lowres = self.raw_hires;
end
else
raw_lowres = double(cat(3,a1,a2,a3));
end
elseif strcmp(self.aamethod,'imresize')
% This is probably the fastest method available at this moment...
raw_lowres = single(imresize(self.raw_hires,1/self.K(2),'bilinear'))/256;
end
warning(w);
%% Place the anti-aliased image in some image on the screen ...
if strcmp(self.figmode,'figure');
% Create a new figure at the same place as the previous
% The content of this new image is just a bitmap...
oldpos = get(gcf,'Position');
self.myaa_figure = figure;
fig = self.myaa_figure;
set(fig,'Menubar','none');
set(fig,'Resize','off');
sz = size(raw_lowres);
set(fig,'Units','pixels');
pos = [oldpos(1:2) sz(2:-1:1)];
set(fig,'Position',pos);
ax = axes;
image(raw_lowres);
set(ax,'Units','pixels');
set(ax,'Position',[1 1 sz(2) sz(1)]);
axis off;
elseif strcmp(self.figmode,'publish');
% Create a new figure at the same place as the previous
% The content of this new image is just a bitmap...
self.myaa_figure = figure;
fig = self.myaa_figure;
current_units = get(self.source_fig,'Units');
set(self.source_fig,'Units','pixels');
pos = get(self.source_fig,'Position');
set(self.source_fig,'Units',current_units);
set(fig,'Position',[pos(1) pos(2) pos(3) pos(4)]);
ax = axes;
image(raw_lowres);
set(ax,'Units','normalized');
set(ax,'Position',[0 0 1 1]);
axis off;
close(self.source_fig);
elseif strcmp(self.figmode,'update');
fig = self.myaa_figure;
figure(fig);
clf;
set(fig,'Menubar','none');
set(fig,'Resize','off');
sz = size(raw_lowres);
set(fig,'Units','pixels');
pos = get(fig,'Position');
pos(3:4) = sz(2:-1:1);
set(fig,'Position',pos);
ax = axes;
image(raw_lowres);
set(ax,'Units','pixels');
set(ax,'Position',[1 1 sz(2) sz(1)]);
axis off;
elseif strcmp(self.figmode,'lazyupdate');
clf;
fig = self.myaa_figure;
sz = size(raw_lowres);
pos = get(fig,'Position');
pos(3:4) = sz(2:-1:1);
set(fig,'Position',pos);
ax = axes;
image(raw_lowres);
set(ax,'Units','pixels');
set(ax,'Position',[1 1 sz(2) sz(1)]);
axis off;
end
%% Store current state
set(gcf,'userdata',self);
set(gcf,'KeyPressFcn',@keypress);
set(gcf,'Interruptible','off');
%% Avoid unnecessary console output
if nargout == 1
varargout(1) = {fig};
end
%% A simple lowpass filter kernel (Butterworth).
% sz is the size of the filter
% subsmp is the downsampling factor to be used later
% n is the degree of the butterworth filter
function kk = lpfilter(sz, subsmp, n)
sz = 2*floor(sz/2)+1; % make sure the size of the filter is odd
cut_frequency = 0.5 / subsmp;
range = (-(sz-1)/2:(sz-1)/2)/(sz-1);
[ii,jj] = ndgrid(range,range);
rr = sqrt(ii.^2+jj.^2);
kk = ifftshift(1./(1+(rr./cut_frequency).^(2*n)));
kk = fftshift(real(ifft2(kk)));
kk = kk./sum(kk(:));
function keypress(src,evnt)
if isempty(evnt.Character)
return
end
recognized = 0;
self = get(gcf,'userdata');
if evnt.Character == '+'
self.K(2) = max(self.K(2).*0.5^(1/2),1);
recognized = 1;
set(gcf,'userdata',self);
myaa('lazyupdate');
elseif evnt.Character == '-'
self.K(2) = min(self.K(2).*2^(1/2),16);
recognized = 1;
set(gcf,'userdata',self);
myaa('lazyupdate');
elseif evnt.Character == ' ' || evnt.Character == 'r' || evnt.Character == 'R'
set(gcf,'userdata',self);
myaa('update');
elseif evnt.Character == 'q'
close(gcf);
elseif find('123456789' == evnt.Character)
self.K = [str2double(evnt.Character) str2double(evnt.Character)];
set(gcf,'userdata',self);
myaa('update');
end
