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%_______________________________________________________________________
%
% core function for drawing random dots motion on presentation screen
%_______________________________________________________________________
%
function [frames,rseed,start_time,end_time,response,response_time] = dotsX_JQK_170320(screenInfo,dotInfo,targets,indCond)
% DOTSX display dots or targets on screen
%
% [frames,rseed,start_time,end_time,response,response_time] = dotsX(screenInfo,dotInfo,targets)
%
% For information on minimum fields of screenInfo and dotInfo arguments, see
% also openExperiment and createDotInfo. The input argument - "targets" is not
% necessary unless showing targets with the dots. Since rex only likes integers,
% almost everything is in visual degrees * 10.
%
% dotInfo.numDotField number of dot patches that will be shown on screen
% dotInfo.coh vertical vectors, dots coherence (0...999) for each
% dot patch
% dotInfo.speed vertical vectors, dots speed (10th deg/sec) for each
% dot patch
% dotInfo.dir vertical vectors, dots direction (degrees) for each
% dot patch
% dotInfo.dotSize size of dots in pixels, same for all patches
% dotInfo.movingDotColor color of dots in RGB for moving dots, same for all patches
% dotInfo.randomDotColor color of dots in RGB for random dots, same for all patches
% dotInfo.maxDotsPerFrame determined by testing video card
% dotInfo.apXYD x, y coordinates, and diameter of aperture(s) in
% visual degrees
% dotInfo.maxDotTime optional to set maximum duration (sec). If not provided,
% dot presentation is terminated only by user response
% dotInfo.trialtype 1 fixed duration, 2 reaction time
% dotInfo.keys a set of keyboard buttons that can terminate the
% presentation of dots (optional)
% dotInfo.mouse a set of mouse buttons that can terminate the
% presentation of dots (optional)
%
% screenInfo.curWindow window pointer on which to plot dots
% screenInfo.center center of the screen in pixels
% screenInfo.ppd pixels per visual degree
% screenInfo.monRefresh monitor refresh value
% screenInfo.dontclear If set to 1, flip will not clear the framebuffer
% after Flip - this allows incremental drawing of
% stimuli. Needs to be zero for dots to be erased.
% screenInfo.rseed random # seed, can be empty set[]
%
% targets.rects dimensions for drawOval
% targets.colors color of targets
% targets.show optional, if only showing certain targets but don't
% want to change targets structure (index number of
% targets) to be shown during dots
%
% Algorithm:
% All calculations take place within a square aperture in which the dots are
% shown. The dots are constructed in 3 sets that are plotted in sequence. For
% each set, the probability that a dot is replotted in motion -- as opposed to
% randomly replaced -- is given by the dotInfo.coh value. This routine generates
% a set of dots as an (ndots,2) matrix of locations, and then plots them. In
% plotting the next set of dots (e.g., set 2), it prepends the preceding set
% (e.g., set 1).
%
% created by MKMK July 2006, based on ShadlenDots by MNS, JIG and others
% Structures are not altered in this function, so should not have memory
% problems from matlab creating new structures.
% CURRENTLY THERE IS AN ALMOST ONE SECOND DELAY FROM THE TIME DOTSX IS
% CALLED UNTIL THE DOTS START ON THE SCREEN! THIS IS BECAUSE OF PRIORITY.
% NEED TO EVALUATE WHETHER PRIORITY IS REALLY NECESSARY.
if nargin < 3
targets = [];
showtar = [];
else
if isfield(targets,'show')
showtar = targets.show;
else
showtar = 1:size(targets.rects,1);
end
end
curWindow = screenInfo.curWindow;
white = [255 255 255];
if isfield(dotInfo,'movingDotColor')
movingDotColor = dotInfo.movingDotColor;
else
movingDotColor = white;
end
if isfield(dotInfo,'randomDotColor')
randomDotColor = dotInfo.randomDotColor;
else
randomDotColor = white;
end
rseed = screenInfo.rseed;
% Query the frame duration
ifi = Screen('GetFlipInterval', curWindow);
% This only matters if using mouse. If dotInfo.mouse doesn't exist, this is
% never checked.
if dotInfo.trialtype(2) == 2
waitpress = 1; % 1 means wait for a mouse press
else
waitpress = 0; % 0 means wait for release
end
% In order to find out if using keypress or mouse, all trials should have spacekey
% for abort, unless its a demo. Spacekey means end experiment after this trial -
% sends abort message to experiment.
keys = [];
abort = [];
if isfield(dotInfo, 'keyLeft')
keys = [dotInfo.keyLeft dotInfo.keyRight];
elseif isfield(dotInfo, 'keySpace')
abort = nan;
end
% mouse
if isfield(dotInfo, 'mouse')
mouse = dotInfo.mouse;
else
mouse = [];
end
start_time = NaN;
end_time= NaN;
response = {NaN, NaN, NaN};
response_time = NaN;
if isfield(targets,'select')
h = targets.select(:,1);
k = targets.select(:,2);
r = targets.select(:,3);
end
% Create the aperture square
%apRect = floor(createTRect(dotInfo.apXYD, screenInfo));
apD = dotInfo.apXYD(:,3); % diameter of aperture
center = repmat(screenInfo.center,size(dotInfo.apXYD(:,1)));
% Change x,y coordinates to pixels (y is inverted - pos on bottom, neg. on top)
center = [center(:,1) + dotInfo.apXYD(:,1)/10*screenInfo.ppd center(:,2) - ...
dotInfo.apXYD(:,2)/10*screenInfo.ppd]; % where you want the center of the aperture
center(:,3) = dotInfo.apXYD(:,3)/2/10*screenInfo.ppd; % add diameter
d_ppd = floor(apD/10 * screenInfo.ppd); % size of aperture in pixels
dotSize = dotInfo.dotSize; % probably better to leave this in pixels, but not sure
% ndots is the number of dots shown per video frame. Dots will be placed in a
% square of the size of aperture.
% - Size of aperture = Apd*Apd/100 sq deg
% - Number of dots per video frame = 16.7 dots per sq deg/sec,
% When rounding up, do not exceed the number of dots that can be plotted in a
% video frame (dotInfo.maxDotsPerFrame). maxDotsPerFrame was originally in
% setupScreen as a field in screenInfo, but makes more sense in createDotInfo as
% a field in dotInfo.
ndots = min(dotInfo.maxDotsPerFrame, ...
ceil(16.7 * apD .* apD * 0.01 / screenInfo.monRefresh));
% determine update frequency of the two contents
checkFlipTimeSecs = 1/dotInfo.Hz_BG;
checkFlipTimeFrames = round(checkFlipTimeSecs / ifi);
frameCounter = 0;
RDMFlipTimeSecs = 1/dotInfo.Hz_RDM;
RDMFlipTimeFrames = round(RDMFlipTimeSecs / ifi);
%% get display size (for BG dots)
sizeX = screenInfo.screenRect(3);
sizeY = screenInfo.screenRect(4);
dontclear = screenInfo.dontclear;
% The main loop
frames = 0;
priorityLevel = MaxPriority(curWindow,'KbCheck');
Priority(priorityLevel);
% Make sure the fixation still on
for i = showtar
Screen('FillOval',screenInfo.curWindow,targets.colors(i,:),targets.rects(i,:));
end
Screen('DrawingFinished',curWindow,dontclear);
%% get starting parameters
currentSegment = 1;
coh = dotInfo.coh{indCond}(currentSegment)./1000;
direction = dotInfo.dir{indCond}(currentSegment);
time = dotInfo.presTime{indCond}(currentSegment);
Contrast = dotInfo.Contrast(indCond);
% How dots are presented: 1st group of dots are shown in the first frame, a 2nd
% group are shown in the second frame, a 3rd group shown in the third frame.
% Then in the next (4th) frame, some percentage of the dots from the 1st frame
% are replotted according to the speed/direction and coherence. Similarly, the
% same is done for the 2nd group, etc.
% initialize dot fields
for df = 1 : dotInfo.numDotField
% dxdy is an N x 2 matrix that gives jumpsize in units on 0..1
% deg/sec * ap-unit/deg * sec/jump = ap-unit/jump
dxdy{df} = repmat((dotInfo.speed(df)/10) * (10/apD(df)) * ...
(3/screenInfo.monRefresh) * [cos(pi*direction(df)/180.0), ...
-sin(pi*direction(df)/180.0)], ndots(df),1);
ss{df} = rand(ndots(df)*3, 2); % array of dot positions raw [x,y]
% Divide dots into three sets
Ls{df} = cumsum(ones(ndots(df),3)) + repmat([0 ndots(df) ndots(df)*2], ...
ndots(df), 1);
loopi(df) = 1; % loops through the three sets of dots
end
%% set up loop and start it (all RDM changes within block)
TimeStamping = [];
StartTime = GetSecs();
BlockOnset = StartTime;
ExperimentProtocol = cell(0);
ExperimentProtocol = [ExperimentProtocol; {'BlockOnset'}, {StartTime}, {[]}, {[]}, {[]}, {coh}, {direction},{Contrast}]
ExperimentProtocol = [ExperimentProtocol; {'RDMUpdate'}, {StartTime}, {[]}, {[]}, {[]}, {coh}, {direction},{Contrast}]
% initiate response cue
KbQueueCreate; KbQueueStart;
while currentSegment <= numel(dotInfo.presTime{indCond})
for df = 1:dotInfo.numDotField
% update movement field with current direction
dxdy{df} = repmat((dotInfo.speed(df)/10) * (10/apD(df)) * ...
(3/screenInfo.monRefresh) * [cos(pi*direction(df)/180.0), ...
-sin(pi*direction(df)/180.0)], ndots(df),1);
% ss is the matrix with 3 sets of dot positions, dots from the last 2
% positions and current dot positions
% Ls picks out the set (e.g., with 5 dots on the screen at a time, 1:5,
% 6:10, or 11:15)
% Lthis has the dot positions from 3 frames ago, which is what is then
Lthis{df} = Ls{df}(:,loopi(df));
% Moved in the current loop. This is a matrix of random numbers - starting
% positions of dots not moving coherently.
this_s{df} = ss{df}(Lthis{df},:);
% Update the loop pointer
loopi(df) = loopi(df)+1;
if loopi(df) == 4
loopi(df) = 1;
end
% Compute new locations, how many dots move coherently
L = rand(ndots(df),1) < coh(df);
% Offset the selected dots
this_s{df}(L,:) = bsxfun(@plus,this_s{df}(L,:),dxdy{df}(L,:));
if sum(~L) > 0
this_s{df}(~L,:) = rand(sum(~L),2); % get new random locations for the rest
end
% Check to see if any positions are greater than 1 or less than 0 which
% is out of the square aperture, and replace with a dot along one of the
% edges opposite from the direction of motion.
N = sum((this_s{df} > 1 | this_s{df} < 0)')' ~= 0;
if sum(N) > 0
xdir = sin(pi*direction(df)/180.0);
ydir = cos(pi*direction(df)/180.0);
% Flip a weighted coin to see which edge to put the replaced dots
if rand < abs(xdir)/(abs(xdir) + abs(ydir))
this_s{df}(find(N==1),:) = [rand(sum(N),1),(xdir > 0)*ones(sum(N),1)];
else
this_s{df}(find(N==1),:) = [(ydir < 0)*ones(sum(N),1),rand(sum(N),1)];
end
end
% Convert for plot
this_x{df} = floor(d_ppd(df) * this_s{df}); % pix/ApUnit
% It assumes that 0 is at the top left, but we want it to be in the
% center, so shift the dots up and left, which means adding half of the
% aperture size to both the x and y directions.
dot_show{df} = (this_x{df} - d_ppd(df)/2)';
end
%% After all computations, flip to draw dots from the previous loop.
% For the first call, this doesn't draw anything.
vbl = Screen('Flip', curWindow,0,dontclear);
TimeStamping = [TimeStamping; vbl];
%% update noise background
if ~mod(frameCounter, checkFlipTimeFrames)
tmp_BG = randperm(sizeX*sizeY,dotInfo.percentOfBG*(sizeX*sizeY));
[pos(1,:), pos(2,:)] = ind2sub([sizeX, sizeY],tmp_BG);
% remove dots within central aperture
inCircle = sqrt((pos(1,:)-center(1,1)).^2 + (pos(2,:)-center(1,2)).^2) < center(df,3); % euclidean distance to center
pos(:,inCircle) = NaN; clear inCircle;
frameCounter = 0;
end
% Increment the counter
frameCounter = frameCounter + 1;
% Draw our texture to the screen
Screen('DrawDots',curWindow,pos,1,Contrast.*randomDotColor);
%% Draw random dots if it's time to update, although nothing is flipped yet
if ~mod(frameCounter, RDMFlipTimeFrames)
for df = 1:dotInfo.numDotField
% NaN out-of-circle dots
xyDis = dot_show{df};
outCircle = sqrt(xyDis(1,:).^2 + xyDis(2,:).^2) + dotInfo.dotSize/2 > center(df,3);
dots2Display = dot_show{df};
dots2Display(:,outCircle) = NaN;
% Screen('DrawDots',curWindow,dots2Display,dotSize,movingDotColor,center(df,1:2));
movingDots = dots2Display(:,L);
randomDots = dots2Display(:,~L);
if size(movingDots,2) > 0
Screen('DrawDots',curWindow,movingDots,dotSize,movingDotColor,center(df,1:2));
end
if size(randomDots,2) > 0
Screen('DrawDots',curWindow,randomDots,dotSize,randomDotColor,center(df,1:2));
end
end
% Draw targets
for i = showtar
Screen('FillOval',screenInfo.curWindow,targets.colors(i,:),targets.rects(i,:));
end
end;
%% check for responses
[keyIsDown, firstPress, ~, ~, ~] = KbQueueCheck;
% encode response
% Note that encoding here might break the update frequency as
% the computations take some time. They are necessary however
% to give instant feedback. In any case, this should only
% affect the cycle on which feedback is received.
if keyIsDown == 1
kp = find(firstPress);
rt = firstPress(kp)-StartTime; % reference to onset of last interval
% encode accuracy
if kp == 80 && direction == 180 % response left
tmp_response = 1;
disp('Correct');
elseif kp == 79 && direction == 0 % response right
disp('Correct');
tmp_response = 1;
else
tmp_response = 0;
disp('Wrong');
end;
ExperimentProtocol = [ExperimentProtocol; {'Resp'}, {firstPress(kp)}, {rt}, {kp}, {tmp_response}, {coh}, {direction}, {Contrast}];
end; % end of response encode loop
%% Prepare next dots presentation
% Tell PTB to get ready while doing computations for next dots presentation
Screen('DrawingFinished',curWindow,dontclear);
%Screen('BlendFunction', curWindow, GL_ONE, GL_ZERO);
frames = frames + 1;
%frameCounter = frameCounter + 1; % counter for checkerboards
if frames == 1
start_time = GetSecs;
end
for df = 1 : dotInfo.numDotField
% Update the dot position array for the next loop
ss{df}(Lthis{df}, :) = this_s{df};
end
% Advance to next RDM state if time has passed
if GetSecs()-StartTime >= dotInfo.presTime{indCond}(currentSegment)
currentSegment = currentSegment + 1;
coh = dotInfo.coh{indCond}(currentSegment)./1000;
direction = dotInfo.dir{indCond}(currentSegment);
time = dotInfo.presTime{indCond}(currentSegment);
StartTime = GetSecs();
ExperimentProtocol = [ExperimentProtocol; {'RDMUpdate'}, {StartTime}, {[]}, {[]}, {[]}, {coh}, {direction}, {Contrast}]
end;
% User may terminate the dots by pressing certain keyboard keys defined by
% "keys". Pressing the escape key will exit the experiment
if not(isempty(keys))
[exitKeyPressed, ~, keyIsDown, secs, keyCode] = checkKeys(dotInfo);
if keyIsDown
% Exit experiment
if exitKeyPressed
response{3} = -1;
return
end
% End trial, have response
if numel(find(keyCode)) == 1 && any(keyCode(keys))
response{3} = find(keyCode(keys));
response_time = secs;
end
end
end
if ~isempty(mouse)
[x,y,buttons] = GetMouse(curWindow);
% check == 0 means exit dots, check == 1 means continuing showing dots
check = 0;
if buttons
% mouse was pressed, if hold is on, and we know fixation position,
% make sure holding the correct place.
if waitpress == 0
if isfield(targets,'select')
check = checkPosition(x,y,h(1),k(1),r(1));
end
else
% If hold is not on, and this is fixed duration, we don't care
% if the subject touches the screen. For reaction time, touching
% means exit dots.
if dotInfo.trialtype(1) == 1
check = 1;
end
end
else
% mouse was not pressed. If waiting for mouse press, continue paradigm
if waitpress == 1
check = 1;
end
end
if ~check
% For fixed duration, exiting early is always an error.
if dotInfo.trialtype(1) == 1
response{2} = 0;
else
% buttons is zero if we are doing reaction time where the subject
% has to hold during fixation, and releasing the mouse signifies
% end of the dots, otherwise should tell you the xy position.
% Eventually, I guess we should make it so we can use two mouse
% buttons as the answer.
if buttons
response{2} = [x y];
else
response{2} = 0;
end
end
response_time = GetSecs;
end
end
end
% Present the last frame of dots
Screen('Flip',curWindow,0,dontclear);
% Erase the last frame of dots, but leave up fixation and targets (if targets
% are up). Make sure the fixation still on.
showTargets(screenInfo,targets,showtar);
end_time = GetSecs;
Priority(0);