implement best fixation option

Author: Remi-Gau

drawFixation.m

@@ -30,6 +30,41 @@ function drawFixation(cfg)
                 CenterRect( ...
                 [0 0 repmat(cfg.fixation.widthPix, 1, 2)], ...
                 cfg.screen.winRect));
+            
+            
+        case 'bestFixation'
+            
+            % Code adapted from:
+            % What is the best fixation target?
+            % DOI 10.1016/j.visres.2012.10.012
+
+            % Draw gap around fixation of 20% the size
+            Screen('FillOval', ...
+                cfg.screen.win, ...
+                cfg.color.background, ...
+                CenterRect( ...
+                [0 0 repmat(1.5 * cfg.fixation.widthPix, 1, 2)], ...
+                cfg.screen.winRect));
+            
+            Screen('FillOval', ...
+                cfg.screen.win, ...
+                cfg.color.black, ...
+                cfg.fixation.outerOval, ...
+                cfg.fixation.widthPix);
+            
+            Screen('DrawLines', ...
+                cfg.screen.win, ...
+                cfg.fixation.allCoords, ...
+                cfg.fixation.widthPix / 3, ...
+                cfg.color.white, ...
+                [cfg.screen.center(1) cfg.screen.center(2)]);
+            
+            Screen('FillOval', ...
+                cfg.screen.win, ...
+                cfg.color.black, ...
+                cfg.fixation.innerOval, ...
+                cfg.fixation.widthPix / 3);
+
     end
 
 end

initFixation.m

@@ -4,16 +4,36 @@
     cfg.fixation = degToPix('width', cfg.fixation, cfg);
     cfg.fixation = degToPix('xDisplacement', cfg.fixation, cfg);
     cfg.fixation = degToPix('yDisplacement', cfg.fixation, cfg);
-
-    if strcmp(cfg.fixation.type, 'cross')
-
-        % Prepare fixation cross
-        cfg.fixation.xCoords = [-cfg.fixation.widthPix cfg.fixation.widthPix 0 0] / 2 + ...
-            cfg.fixation.xDisplacementPix;
-        cfg.fixation.yCoords = [0 0 -cfg.fixation.widthPix cfg.fixation.widthPix] / 2 + ...
-            cfg.fixation.yDisplacementPix;
-        cfg.fixation.allCoords = [cfg.fixation.xCoords; cfg.fixation.yCoords];
-
+    
+    % Prepare fixation cross
+    xLine = [-cfg.fixation.widthPix cfg.fixation.widthPix 0 0] / 2;
+    yLine = [0 0 -cfg.fixation.widthPix cfg.fixation.widthPix] / 2;
+    
+    cfg.fixation.xCoords =  xLine + cfg.fixation.xDisplacementPix;
+    cfg.fixation.yCoords =  yLine + cfg.fixation.yDisplacementPix;
+    
+    cfg.fixation.allCoords = [cfg.fixation.xCoords; cfg.fixation.yCoords];
+    
+    switch cfg.fixation.type
+        
+        case 'bestFixation'
+            
+            % Code adapted from:
+            % What is the best fixation target?
+            % DOI 10.1016/j.visres.2012.10.012
+            
+            cfg.fixation.outerOval = [...
+                cfg.screen.center(1)-cfg.fixation.widthPix/2, ...
+                cfg.screen.center(2)-cfg.fixation.widthPix/2, ...
+                cfg.screen.center(1)+cfg.fixation.widthPix/2, ...
+                cfg.screen.center(2)+cfg.fixation.widthPix/2];
+            
+            cfg.fixation.innerOval = [...
+                cfg.screen.center(1)-cfg.fixation.widthPix/6, ...
+                cfg.screen.center(2)-cfg.fixation.widthPix/6, ...
+                cfg.screen.center(1)+cfg.fixation.widthPix/6, ...
+                cfg.screen.center(2)+cfg.fixation.widthPix/6];
+            
     end
-
+    
 end