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                // This file demonstrates how to present multiple images in random order in succession.
// That is, Rapid serial visual presentation (RSVP) 

const images = [

    const jsPsych = initJsPsych({
        on_finish: function() {
    console.log(`jsPsych Version ${jsPsych.version()}`)

    const pixi_flag ='pixi_flag') === '1' ? true : false;

    const first_instruction = {
        type: jsPsychHtmlButtonResponse,
        stimulus: 'Click on the Start button.',
        choices: ['Start'],
        prompt: "This is a sample program for the jspsych-psychophysics plugin.",

    const preload_trial = {
        type: jsPsychPreload,
        images: images

    const stimulus_object = []

    for (let i = 0; i < images.length; i++) {
        const temporal_object = {
            obj_type: 'image',
            file: 'This will be overwritten later.'

    const viewing_time = 200 // ms
    const isi = 50 // ms

    const instruction = {
        obj_type: 'text',
        content: 'Press the spacebar to continue, or any other key to abort.',
        font: "22px 'Arial'",
        text_color: 'white',
        show_start_time: (viewing_time + isi) * images.length

    const rsvp_trial = {
        type: jsPsychPsychophysics,
        pixi: pixi_flag,
        stimuli: stimulus_object, // Note that the last element of the stimulus_object is the instruction.
        response_start_time: (viewing_time + isi) * images.length - isi, // not to respond until all images are presented.
        on_start: function(trial){
            // Set parameters for each image dynamically.

            const rand_images = jsPsych.randomization.shuffle(images)

            for (let i = 0; i < images.length; i++) {
                trial.stimuli[i].file = rand_images[i]
                const start = (viewing_time + isi)  * i;
                trial.stimuli[i].show_start_time = start;
                trial.stimuli[i].show_end_time = start  + viewing_time 

    const loop_node = {
        timeline: [rsvp_trial],
        loop_function: function(data){
            if(jsPsych.pluginAPI.compareKeys(data.values()[0].response, ' ')){
                return true;
            } else {
                return false;
    }[preload_trial, first_instruction, loop_node])