% Clear the workspace and the screen close all; clear; sca % Here we call some default settings for setting up Psychtoolbox PsychDefaultSetup(2); % Get the screen numbers screens = Screen('Screens'); % Select the external screen if it is present, else revert to the native % screen screenNumber = max(screens); % Define black, white and grey black = BlackIndex(screenNumber); white = WhiteIndex(screenNumber); grey = white / 2; % Open an on screen window and color it grey [window, windowRect] = PsychImaging('OpenWindow', screenNumber, grey); % Set the blend funciton for the screen Screen('BlendFunction', window, 'GL_SRC_ALPHA', 'GL_ONE_MINUS_SRC_ALPHA'); % Get the size of the on screen window in pixels % For help see: Screen WindowSize? [screenXpixels, screenYpixels] = Screen('WindowSize', window); % Get the centre coordinate of the window in pixels % For help see: help RectCenter [xCenter, yCenter] = RectCenter(windowRect); % Lets write three lines of text, the first and second right after one % another, and the third with a line space in between. To add line spaces % we use the special characters "\n" line1 = 'Hello World'; line2 = '\n This is the second line'; line3 = '\n\n This is the third line'; % Draw all the text in one go Screen('TextSize', window, 70); DrawFormattedText(window, [line1 line2 line3],... 'center', screenYpixels * 0.25, white); % Flip to the screen Screen('Flip', window); % Now we have drawn to the screen we wait for a keyboard button press (any % key) to terminate the demo KbStrokeWait; % Clear the screen sca;