var jsPsychImageKeyboardResponse = (function (jspsych) { 'use strict'; const info = { name: "image-keyboard-response", parameters: { /** The image to be displayed */ stimulus: { type: jspsych.ParameterType.IMAGE, pretty_name: "Stimulus", default: undefined, }, /** Set the image height in pixels */ stimulus_height: { type: jspsych.ParameterType.INT, pretty_name: "Image height", default: null, }, /** Set the image width in pixels */ stimulus_width: { type: jspsych.ParameterType.INT, pretty_name: "Image width", default: null, }, /** Maintain the aspect ratio after setting width or height */ maintain_aspect_ratio: { type: jspsych.ParameterType.BOOL, pretty_name: "Maintain aspect ratio", default: true, }, /** Array containing the key(s) the subject is allowed to press to respond to the stimulus. */ choices: { type: jspsych.ParameterType.KEYS, pretty_name: "Choices", default: "ALL_KEYS", }, /** Any content here will be displayed below the stimulus. */ prompt: { type: jspsych.ParameterType.HTML_STRING, pretty_name: "Prompt", default: null, }, /** How long to show the stimulus. */ stimulus_duration: { type: jspsych.ParameterType.INT, pretty_name: "Stimulus duration", default: null, }, /** How long to show trial before it ends */ trial_duration: { type: jspsych.ParameterType.INT, pretty_name: "Trial duration", default: null, }, /** If true, trial will end when subject makes a response. */ response_ends_trial: { type: jspsych.ParameterType.BOOL, pretty_name: "Response ends trial", default: true, }, /** * If true, the image will be drawn onto a canvas element (prevents blank screen between consecutive images in some browsers). * If false, the image will be shown via an img element. */ render_on_canvas: { type: jspsych.ParameterType.BOOL, pretty_name: "Render on canvas", default: true, }, }, }; /** * **image-keyboard-response** * * jsPsych plugin for displaying an image stimulus and getting a keyboard response * * @author Josh de Leeuw * @see {@link https://www.jspsych.org/plugins/jspsych-image-keyboard-response/ image-keyboard-response plugin documentation on jspsych.org} */ class ImageKeyboardResponsePlugin { constructor(jsPsych) { this.jsPsych = jsPsych; } trial(display_element, trial) { var height, width; if (trial.render_on_canvas) { var image_drawn = false; // first clear the display element (because the render_on_canvas method appends to display_element instead of overwriting it with .innerHTML) if (display_element.hasChildNodes()) { // can't loop through child list because the list will be modified by .removeChild() while (display_element.firstChild) { display_element.removeChild(display_element.firstChild); } } // create canvas element and image var canvas = document.createElement("canvas"); canvas.id = "jspsych-image-keyboard-response-stimulus"; canvas.style.margin = "0"; canvas.style.padding = "0"; var ctx = canvas.getContext("2d"); var img = new Image(); img.onload = () => { // if image wasn't preloaded, then it will need to be drawn whenever it finishes loading if (!image_drawn) { getHeightWidth(); // only possible to get width/height after image loads ctx.drawImage(img, 0, 0, width, height); } }; img.src = trial.stimulus; // get/set image height and width - this can only be done after image loads because uses image's naturalWidth/naturalHeight properties const getHeightWidth = () => { if (trial.stimulus_height !== null) { height = trial.stimulus_height; if (trial.stimulus_width == null && trial.maintain_aspect_ratio) { width = img.naturalWidth * (trial.stimulus_height / img.naturalHeight); } } else { height = img.naturalHeight; } if (trial.stimulus_width !== null) { width = trial.stimulus_width; if (trial.stimulus_height == null && trial.maintain_aspect_ratio) { height = img.naturalHeight * (trial.stimulus_width / img.naturalWidth); } } else if (!(trial.stimulus_height !== null && trial.maintain_aspect_ratio)) { // if stimulus width is null, only use the image's natural width if the width value wasn't set // in the if statement above, based on a specified height and maintain_aspect_ratio = true width = img.naturalWidth; } canvas.height = height; canvas.width = width; }; getHeightWidth(); // call now, in case image loads immediately (is cached) // add canvas and draw image display_element.insertBefore(canvas, null); if (img.complete && Number.isFinite(width) && Number.isFinite(height)) { // if image has loaded and width/height have been set, then draw it now // (don't rely on img onload function to draw image when image is in the cache, because that causes a delay in the image presentation) ctx.drawImage(img, 0, 0, width, height); image_drawn = true; } // add prompt if there is one if (trial.prompt !== null) { display_element.insertAdjacentHTML("beforeend", trial.prompt); } } else { // display stimulus as an image element var html = ''; // add prompt if (trial.prompt !== null) { html += trial.prompt; } // update the page content display_element.innerHTML = html; // set image dimensions after image has loaded (so that we have access to naturalHeight/naturalWidth) var img = display_element.querySelector("#jspsych-image-keyboard-response-stimulus"); if (trial.stimulus_height !== null) { height = trial.stimulus_height; if (trial.stimulus_width == null && trial.maintain_aspect_ratio) { width = img.naturalWidth * (trial.stimulus_height / img.naturalHeight); } } else { height = img.naturalHeight; } if (trial.stimulus_width !== null) { width = trial.stimulus_width; if (trial.stimulus_height == null && trial.maintain_aspect_ratio) { height = img.naturalHeight * (trial.stimulus_width / img.naturalWidth); } } else if (!(trial.stimulus_height !== null && trial.maintain_aspect_ratio)) { // if stimulus width is null, only use the image's natural width if the width value wasn't set // in the if statement above, based on a specified height and maintain_aspect_ratio = true width = img.naturalWidth; } img.style.height = height.toString() + "px"; img.style.width = width.toString() + "px"; } // store response var response = { rt: null, key: null, }; // function to end trial when it is time const end_trial = () => { // kill any remaining setTimeout handlers this.jsPsych.pluginAPI.clearAllTimeouts(); // kill keyboard listeners if (typeof keyboardListener !== "undefined") { this.jsPsych.pluginAPI.cancelKeyboardResponse(keyboardListener); } // gather the data to store for the trial var trial_data = { rt: response.rt, stimulus: trial.stimulus, response: response.key, }; // clear the display display_element.innerHTML = ""; // move on to the next trial this.jsPsych.finishTrial(trial_data); }; // function to handle responses by the subject var after_response = (info) => { // after a valid response, the stimulus will have the CSS class 'responded' // which can be used to provide visual feedback that a response was recorded display_element.querySelector("#jspsych-image-keyboard-response-stimulus").className += " responded"; // only record the first response if (response.key == null) { response = info; } if (trial.response_ends_trial) { end_trial(); } }; // start the response listener if (trial.choices != "NO_KEYS") { var keyboardListener = this.jsPsych.pluginAPI.getKeyboardResponse({ callback_function: after_response, valid_responses: trial.choices, rt_method: "performance", persist: false, allow_held_key: false, }); } // hide stimulus if stimulus_duration is set if (trial.stimulus_duration !== null) { this.jsPsych.pluginAPI.setTimeout(() => { display_element.querySelector("#jspsych-image-keyboard-response-stimulus").style.visibility = "hidden"; }, trial.stimulus_duration); } // end trial if trial_duration is set if (trial.trial_duration !== null) { this.jsPsych.pluginAPI.setTimeout(() => { end_trial(); }, trial.trial_duration); } else if (trial.response_ends_trial === false) { console.warn("The experiment may be deadlocked. Try setting a trial duration or set response_ends_trial to true."); } } simulate(trial, simulation_mode, simulation_options, load_callback) { if (simulation_mode == "data-only") { load_callback(); this.simulate_data_only(trial, simulation_options); } if (simulation_mode == "visual") { this.simulate_visual(trial, simulation_options, load_callback); } } simulate_data_only(trial, simulation_options) { const data = this.create_simulation_data(trial, simulation_options); this.jsPsych.finishTrial(data); } simulate_visual(trial, simulation_options, load_callback) { const data = this.create_simulation_data(trial, simulation_options); const display_element = this.jsPsych.getDisplayElement(); this.trial(display_element, trial); load_callback(); if (data.rt !== null) { this.jsPsych.pluginAPI.pressKey(data.response, data.rt); } } create_simulation_data(trial, simulation_options) { const default_data = { stimulus: trial.stimulus, rt: this.jsPsych.randomization.sampleExGaussian(500, 50, 1 / 150, true), response: this.jsPsych.pluginAPI.getValidKey(trial.choices), }; const data = this.jsPsych.pluginAPI.mergeSimulationData(default_data, simulation_options); this.jsPsych.pluginAPI.ensureSimulationDataConsistency(trial, data); return data; } } ImageKeyboardResponsePlugin.info = info; return ImageKeyboardResponsePlugin; })(jsPsychModule);