pblob.m

function ProceduralGaussBlob(ngabors, nlines)

PsychDefaultSetup(2);

if nargin < 1 || isempty(ngabors)
    ngabors = 200;
end

screenid = max(Screen('Screens'));
Screen('Preference', 'SkipSyncTests', 1)
PsychImaging('PrepareConfiguration');
PsychImaging('AddTask', 'General', 'FloatingPoint32BitIfPossible');
[win, winRect] = PsychImaging('OpenWindow', screenid, 0.5);

[w, h] = RectSize(winRect);

if nargin < 1 || isempty(nlines)
    nlines = 2*w;
end

ifi = Screen('GetFlipInterval', win);

%%% drow Linemasks %%%
LineAngle = 45*pi/180;
LineLength = 2*w;
for i = 1:nlines
    XCenter = (-nlines/2+i)*sin(LineAngle);
    YCenter = (-nlines/2+i)*cos(LineAngle);
    X(2*i-1) = XCenter-LineLength/2*cos(LineAngle);
    X(2*i) = XCenter+LineLength/2*cos(LineAngle);
    Y(2*i-1) = YCenter+LineLength/2*sin(LineAngle);
    Y(2*i) = YCenter-LineLength/2*sin(LineAngle);
end
XYMatrix = [X+w/2; Y+h/2];

color = ones(1,nlines).*rand(1,nlines);
for i = 1:nlines
    ColorLines(2*i-1) = color(i);
    ColorLines(2*i) = color(i);
end
ColorMatrix = repmat(ColorLines,3,1);

%%% drow GaussBolbs %%%
half_size = 32;
tw = 2*half_size+1;
th = 2*half_size+1;

sc = 10.0;
contrast = 10;
aspectratio = 1.0;

blobpars = repmat([contrast, sc, aspectratio, 1]', 1, ngabors);

blobpars(1,:) = blobpars(1,:).*((rand(1,ngabors)-0.5)*2);

blobtex = CreateProceduralGaussBlob(win, tw * 2, th * 2);

scale = 0.5;

texrect = Screen('Rect', blobtex)*scale;
inrect = repmat(texrect', 1, ngabors);

dstRects = zeros(4, ngabors);
for i=1:ngabors
    dstRects(:, i) = CenterRectOnPoint(texrect, rand * w, rand * h)';
end

vbl = Screen('Flip', win);

while ~KbCheck(-1)
    Screen('BlendFunction', win, GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
    %Screen('DrawLines', win, XYMatrix, [], ColorMatrix, [], 2, []);
    Screen('BlendFunction', win, GL_ONE, GL_ONE);
    Screen('DrawTextures', win, blobtex, [], dstRects, [], [], [], [], [], kPsychDontDoRotation, blobpars);
    Screen('DrawingFinished', win);
    
    [x, y] = RectCenterd(dstRects); 
    x = mod(x + 2, w);
    y = mod(y - 2, h);

    dstRects = CenterRectOnPointd(inrect .* ones(4,ngabors), x, y);

    vbl = Screen('Flip', win, vbl + 0.5 * ifi);

end

vbl = Screen('Flip', win);

sca;

return