images.m

function images()
    import stage.core.*;

    % Open a window in windowed-mode and create a canvas. 'disableDwm' = false for demo only!
    window = Window([640, 480], false);
    canvas = Canvas(window, 'disableDwm', false);

    % Read a few images from file.
    imagesDir = fullfile(fileparts(mfilename('fullpath')), 'Images');
    butterflyImage = imread(fullfile(imagesDir, 'butterfly.jpg'));

    [horseImage, ~, horseAlpha] = imread(fullfile(imagesDir, 'horse.png'));
    horseImage(:, :, 4) = horseAlpha;

    % Create a few image stimuli.
    butterfly = stage.builtin.stimuli.Image(butterflyImage);
    butterfly.size = [size(butterflyImage, 2), size(butterflyImage, 1)];
    butterfly.position = canvas.size / 2;

    mask = Mask.createGaussianEnvelope();
    butterfly.setMask(mask);

    darkHorse = stage.builtin.stimuli.Image(horseImage);
    darkHorse.size = [size(horseImage, 2), size(horseImage, 1)];
    darkHorse.color = 0;

    lightHorse = stage.builtin.stimuli.Image(horseImage);
    lightHorse.size = [-size(horseImage, 2)/2, size(horseImage, 1)/2];
    lightHorse.color = 1;

    % Create controllers to change the horse positions as functions of time.
    lightHorsePositionController = stage.builtin.controllers.PropertyController(lightHorse, 'position', @(state)[canvas.width-state.time*75-100, canvas.height/2]);
    darkHorsePositionController = stage.builtin.controllers.PropertyController(darkHorse, 'position', @(state)[state.time*100, canvas.height/2-50]);

    % Create a 6 second presentation and add the stimuli and controllers.
    presentation = Presentation(6);
    presentation.addStimulus(lightHorse);
    presentation.addStimulus(butterfly);
    presentation.addStimulus(darkHorse);
    presentation.addController(lightHorsePositionController);
    presentation.addController(darkHorsePositionController);

    % Play the presentation on the canvas!
    presentation.play(canvas);

    % Window automatically closes when the window object is deleted.
end