~ubuntu-branches/ubuntu/trusty/psychtoolbox-3/trusty-proposed

% MouseTraceDemo4

%

% ___________________________________________________________________

% 

% Draw a curve with the mouse. Same as MouseTraceDemo, but asks

% Screen('Flip') to not clear the framebuffer after flip. This way,

% we don't need to redraw the whole mouse trace in each frame.

% Uses imaging pipeline via PsychImaging for optimal performance

% on modern hardware, as opposed to old style method shown in

% MouseTraceDemo2, which was appropriate before the year 2007.

% ___________________________________________________________________

%

% See also: PsychDemos, MouseTraceDemo, GetMouse.

%

% HISTORY

%                       

% 4/1/2013  mk       Derived from MouseTraceDemo2.

 

try

    % Open up a window on the screen and clear it.

    whichScreen = max(Screen('Screens'));

    PsychImaging('PrepareConfiguration');

    PsychImaging('AddTask', 'General', 'UseVirtualFramebuffer');

    [theWindow,theRect] = PsychImaging('OpenWindow', whichScreen, 0);

 

    % Move the cursor to the center of the screen

    theX = theRect(RectRight)/2;

    theY = theRect(RectBottom)/2;

    SetMouse(theX,theY);

 

    % Wait for a click and hide the cursor

    Screen(theWindow,'TextSize',24);

    Screen(theWindow,'DrawText','Drag mouse (i.e. hold button down) to draw',50,50,255);

    Screen('Flip', theWindow);

    while (1)

        [x,y,buttons] = GetMouse(theWindow);

        if buttons(1)

          break;

        end

    end

    Screen(theWindow,'DrawText','Release button to finish',50,50,255);

 

    HideCursor;

 

    % Loop and track the mouse, drawing the contour

    [theX,theY] = GetMouse(theWindow);

    thePoints = [theX theY];

    Screen(theWindow,'DrawLine',255,theX,theY,theX,theY);

    % Set the 'dontclear' flag of Flip to 1 to prevent erasing the

    % frame-buffer:

    Screen('Flip', theWindow, 0, 1);

    while (1)

        [x,y,buttons] = GetMouse(theWindow);    

        if ~buttons(1)

            break;

        end

        if (x ~= theX || y ~= theY)

            thePoints = [thePoints ; x y]; %#ok<AGROW>

            [numPoints, two]=size(thePoints);

            % Only draw the most recent line segment: This is possible,

            % because...

            Screen(theWindow,'DrawLine',128,thePoints(numPoints-1,1),thePoints(numPoints-1,2),thePoints(numPoints,1),thePoints(numPoints,2));

            % ...we ask Flip to not clear the framebuffer after flipping:

            Screen('Flip', theWindow, 0, 1);

            theX = x; theY = y;

        end

    end

 

    % Close up

    Screen(theWindow,'DrawText','Click mouse to finish',50,50,255);

    ShowCursor;

    Screen(theWindow,'Close');

 

    % Plot the contour in a Matlab figure

    plot(thePoints(:,1),theRect(RectBottom)-thePoints(:,2));

catch

    Screen('CloseAll')

    ShowCursor;

    psychrethrow(psychlasterror);

end %try..catch..