region of interest mouse click response and if statements using psychtoolbox-3

Hi All,

I'm wondering how I can specify a region of interest on an image using Psychtoolbox-3. I need the ROI to be invisible to the user. I would like the user to make a left mouse click and then use an if statement (that depends on whether they clicked inside or outside of the ROI) to determine what happens next. PLEASE HELP!!

I currently have this, but it's not working (i'm not even sure if the load function is calling the roi back):

%I used drawrectangle to make an roi on an image and then saved it to roi.mat 
load('roi.mat') 
[clicks,x,y,WhichButton] = GetClicks; 
    if inROI(roi,x,y) 
       texture = Screen('MakeTexture', windowPtr, YouWon);
       Screen('DrawTexture', windowPtr, texture);
       Screen('Flip', windowPtr); 
       WaitSecs(1);
    else
       texture = Screen('MakeTexture', windowPtr, TryAgain);
       Screen('DrawTexture', windowPtr, texture);
       Screen('Flip', windowPtr); 
       WaitSecs(1);
    end
                   
             

Answer 1

[Srimouli Rukmabhatla]

Hi Rubina,

Please do ensure that the required variables are loaded in ‘roi.mat’ file . inROI function is to check the given co-ordinates are within the Region Of Interest, If co-ordinates are within the ROI it return 1 else it return 0 .Please do refer the inROI doucumentaion link https://www.mathworks.com/help/images/ref/inroi.html.