use preTrialSetup to prepare MT and MST trials

Author: Remi-Gau

subfun/preTrialSetup.m

@@ -1,21 +1,37 @@
 function varargout = preTrialSetup(varargin)
     % varargout = postInitializatinSetup(varargin)
 
-    % generic function to finalize some set up after psychtoolbox has been
-    % initialized
+    % generic function to prepare some structure before each trial
 
     [cfg, iBlock, iEvent] = deal(varargin{:});
 
     % set direction, speed of that event and if it is a target
     thisEvent.trial_type = cfg.design.blockNames{iBlock};
     thisEvent.direction = cfg.design.directions(iBlock, iEvent);
     thisEvent.speed = cfg.design.speeds(iBlock, iEvent);
-    thisEvent.target = cfg.design.fixationTargets(iBlock, iEvent);
+    thisEvent.target = cfg.design.fixationTargets(iBlock, iEvent);        
 
     % If this frame shows a target we change the color of the cross
     thisFixation.fixation = cfg.fixation;
     thisFixation.screen = cfg.screen;
+    
+    switch thisEvent.trial_type
+        case 'fixation_right'
+            cfg.aperture.xPosPix = -abs(cfg.aperture.xPosPix);
+            
+            thisFixation.fixation.xDisplacement = cfg.aperture.xPos;
+            thisFixation = initFixation(thisFixation);
+    
+        case 'fixation_left'
+            cfg.aperture.xPosPix = +abs(cfg.aperture.xPosPix);
+            
+            thisFixation.fixation.xDisplacement = -cfg.aperture.xPos;
+            thisFixation = initFixation(thisFixation);
+            
+    end
+
+    varargout = {thisEvent, thisFixation, cfg};
+    
 
-    varargout = {thisEvent, thisFixation};
 
 end

visualLocTranslational.m

@@ -79,7 +79,7 @@
             % Check for experiment abortion from operator
             checkAbort(cfg, cfg.keyboard.keyboard);
 
-            [thisEvent, thisFixation] = preTrialSetup(cfg, iBlock, iEvent);
+            [thisEvent, thisFixation, cfg] = preTrialSetup(cfg, iBlock, iEvent);
 
             % we wait for a trigger every 2 events
             if cfg.pacedByTriggers.do && mod(iEvent, 2) == 1