jsPsych/plugins/jspsych-visual-search-circle.js

260 lines
7.8 KiB
JavaScript

/**
*
* jspsych-visual-search-circle
* Josh de Leeuw
*
* display a set of objects, with or without a target, equidistant from fixation
* subject responds to whether or not the target is present
*
* based on code written for psychtoolbox by Ben Motz
*
* documentation: docs.jspsych.org
*
**/
jsPsych.plugins["visual-search-circle"] = (function() {
var plugin = {};
jsPsych.pluginAPI.registerPreload('visual-search-circle', 'target', 'image');
jsPsych.pluginAPI.registerPreload('visual-search-circle', 'foil', 'image');
jsPsych.pluginAPI.registerPreload('visual-search-circle', 'fixation_image', 'image');
plugin.info = {
name: 'visual-search-circle',
description: '',
parameters: {
target: {
type: jsPsych.plugins.parameterType.IMAGE,
pretty_name: 'Target',
default: undefined,
description: 'The image to be displayed.'
},
foil: {
type: jsPsych.plugins.parameterType.IMAGE,
pretty_name: 'Foil',
default: undefined,
description: 'Path to image file that is the foil/distractor.'
},
fixation_image: {
type: jsPsych.plugins.parameterType.IMAGE,
pretty_name: 'Fixation image',
default: undefined,
description: 'Path to image file that is a fixation target.'
},
set_size: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Set size',
default: undefined,
description: 'How many items should be displayed?'
},
target_present: {
type: jsPsych.plugins.parameterType.BOOL,
pretty_name: 'Target present',
default: true,
description: 'Is the target present?'
},
target_size: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Target size',
array: true,
default: [50, 50],
description: 'Two element array indicating the height and width of the search array element images.'
},
fixation_size: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Fixation size',
array: true,
default: [16, 16],
description: 'Two element array indicating the height and width of the fixation image.'
},
circle_diameter: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Circle diameter',
default: 250,
description: 'The diameter of the search array circle in pixels.'
},
target_present_key: {
type: jsPsych.plugins.parameterType.KEY,
pretty_name: 'Target present key',
default: 'j',
description: 'The key to press if the target is present in the search array.'
},
target_absent_key: {
type: jsPsych.plugins.parameterType.KEY,
pretty_name: 'Target absent key',
default: 'f',
description: 'The key to press if the target is not present in the search array.'
},
trial_duration: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Trial duration',
default: null,
description: 'The maximum duration to wait for a response.'
},
fixation_duration: {
type: jsPsych.plugins.parameterType.INT,
pretty_name: 'Fixation duration',
default: 1000,
description: 'How long to show the fixation image for before the search array (in milliseconds).'
}
}
}
plugin.trial = function(display_element, trial) {
// circle params
var diam = trial.circle_diameter; // pixels
var radi = diam / 2;
var paper_size = diam + trial.target_size[0];
// stimuli width, height
var stimh = trial.target_size[0];
var stimw = trial.target_size[1];
var hstimh = stimh / 2;
var hstimw = stimw / 2;
// fixation location
var fix_loc = [Math.floor(paper_size / 2 - trial.fixation_size[0] / 2), Math.floor(paper_size / 2 - trial.fixation_size[1] / 2)];
// possible stimulus locations on the circle
var display_locs = [];
var possible_display_locs = trial.set_size;
var random_offset = Math.floor(Math.random() * 360);
for (var i = 0; i < possible_display_locs; i++) {
display_locs.push([
Math.floor(paper_size / 2 + (cosd(random_offset + (i * (360 / possible_display_locs))) * radi) - hstimw),
Math.floor(paper_size / 2 - (sind(random_offset + (i * (360 / possible_display_locs))) * radi) - hstimh)
]);
}
// get target to draw on
display_element.innerHTML += '<div id="jspsych-visual-search-circle-container" style="position: relative; width:' + paper_size + 'px; height:' + paper_size + 'px"></div>';
var paper = display_element.querySelector("#jspsych-visual-search-circle-container");
// check distractors - array?
if(!Array.isArray(trial.foil)){
fa = [];
for(var i=0; i<trial.set_size; i++){
fa.push(trial.foil);
}
trial.foil = fa;
}
show_fixation();
function show_fixation() {
// show fixation
//var fixation = paper.image(trial.fixation_image, fix_loc[0], fix_loc[1], trial.fixation_size[0], trial.fixation_size[1]);
paper.innerHTML += "<img src='"+trial.fixation_image+"' style='position: absolute; top:"+fix_loc[0]+"px; left:"+fix_loc[1]+"px; width:"+trial.fixation_size[0]+"px; height:"+trial.fixation_size[1]+"px;'></img>";
// wait
jsPsych.pluginAPI.setTimeout(function() {
// after wait is over
show_search_array();
}, trial.fixation_duration);
}
function show_search_array() {
var search_array_images = [];
var to_present = [];
if(trial.target_present){
to_present.push(trial.target);
}
to_present = to_present.concat(trial.foil);
for (var i = 0; i < display_locs.length; i++) {
paper.innerHTML += "<img src='"+to_present[i]+"' style='position: absolute; top:"+display_locs[i][0]+"px; left:"+display_locs[i][1]+"px; width:"+trial.target_size[0]+"px; height:"+trial.target_size[1]+"px;'></img>";
}
var trial_over = false;
var after_response = function(info) {
trial_over = true;
var correct = false;
if ((jsPsych.pluginAPI.compareKeys(info.key, trial.target_present_key)) && trial.target_present ||
(jsPsych.pluginAPI.compareKeys(info.key, trial.target_absent_key)) && !trial.target_present) {
correct = true;
}
clear_display();
end_trial(info.rt, correct, info.key);
}
var valid_keys = [trial.target_present_key, trial.target_absent_key];
key_listener = jsPsych.pluginAPI.getKeyboardResponse({
callback_function: after_response,
valid_responses: valid_keys,
rt_method: 'performance',
persist: false,
allow_held_key: false
});
if (trial.trial_duration !== null) {
jsPsych.pluginAPI.setTimeout(function() {
if (!trial_over) {
jsPsych.pluginAPI.cancelKeyboardResponse(key_listener);
trial_over = true;
var rt = null;
var correct = 0;
var key_press = null;
clear_display();
end_trial(rt, correct, key_press);
}
}, trial.trial_duration);
}
function clear_display() {
display_element.innerHTML = '';
}
}
function end_trial(rt, correct, key_press) {
// data saving
var trial_data = {
correct: correct,
rt: rt,
response: key_press,
locations: display_locs,
target_present: trial.target_present,
set_size: trial.set_size
};
// go to next trial
jsPsych.finishTrial(trial_data);
}
};
// helper function for determining stimulus locations
function cosd(num) {
return Math.cos(num / 180 * Math.PI);
}
function sind(num) {
return Math.sin(num / 180 * Math.PI);
}
return plugin;
})();