// This file demonstrates how to present lines.
    // There are two ways to define a line.
    // Note: You can not specify both the angle and positions for the same object.
    
    const jsPsych = initJsPsych({
        on_finish: function() {
            jsPsych.data.displayData();
        }
    })
    console.log(`jsPsych Version ${jsPsych.version()}`)

    const pixi_flag = jsPsych.data.getURLVariable('pixi_flag') === '1' ? true : false;

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

    // The line_object1 defines a line using the angle and line_length.
    const line_object1 = {
        obj_type: 'line',        
        startX: 200, // location in the canvas
        startY: 400,
        angle: 45,
        line_length: 200,
        line_width: 4,
        line_color: 'black', // You can use the HTML color name instead of the HEX color.
        show_start_time: 500, // ms after the start of the trial
        endX: 300,
        endY: 400,
        motion_start_time: 1500,
        motion_end_time: 3000,
    }

    // The line_object2 defines a line using the start and end positions.
    const line_object2 = {
        obj_type: 'line',
        x1: 300,
        y1: 200,
        x2: 200,
        y2: 400,
        line_width: 6,
        line_color: 'red', // You can use the HTML color name instead of the HEX color.
        show_start_time: 1000, // ms after the start of the trial
        vert_pix_frame: 5,
        motion_start_time: 1500,
        motion_end_time: 3000,
    }

    const trial = {
        type: jsPsychPsychophysics,
        pixi: pixi_flag,
        stimuli: [line_object1, line_object2],
    }

    jsPsych.run([instruction, trial])