webgazer-calibrate¶
Current version: 1.0.3. See version history.
This plugin can be used to calibrate the WebGazer extension. For a narrative description of eye tracking with jsPsych, see the eye tracking overview.
Parameters¶
In addition to the parameters available in all plugins, this plugin accepts the following parameters. Parameters with a default value of undefined must be specified. Other parameters can be left unspecified if the default value is acceptable.
| Parameter | Type | Default Value | Description |
|---|---|---|---|
| calibration_points | array | [[10,10], [10,50], [10,90], [50,10], [50,50], [50,90], [90,10], [90,50], [90,90]] |
Array of points in [x,y] coordinates. Specified as a percentage of the screen width and height, from the left and top edge. The default grid is 9 points. |
| calibration_mode | string | 'click' |
Can specify click to have participants click on calibration points or view to have participants passively watch calibration points. |
| repetitions_per_point | numeric | 1 | The number of times to repeat the sequence of calibration points. |
| point_size | numeric | 20 | Diameter of the calibration points in pixels. |
| randomize_calibration_order | bool | false |
Whether to randomize the order of the calibration points. |
| time_to_saccade | numeric | 1000 | If calibration_mode is set to view, then this is the delay before calibrating after showing a point. Gives the participant time to fixate on the new target before assuming that the participant is looking at the target. |
| time_per_point | numeric | 1000 | If calibration_mode is set to view, then this is the length of time to show a point while calibrating. Note that if click calibration is used then the point will remain on the screen until clicked. |
Data Generated¶
In addition to the default data collected by all plugins, this plugin collects the following data for each trial.
| Name | Type | Value |
|---|---|---|
No data currently added by this plugin. Use the webgazer-validate plugin to measure the precision and accuracy of calibration.
Simulation Mode¶
This plugin does not yet support simulation mode.
Install¶
Using the CDN-hosted JavaScript file:
<script src="https://unpkg.com/@jspsych/plugin-webgazer-calibrate@1.0.3"></script>
Using the JavaScript file downloaded from a GitHub release dist archive:
<script src="jspsych/plugin-webgazer-calibrate.js"></script>
Using NPM:
npm install @jspsych/plugin-webgazer-calibrate
import webgazerCalibrate from '@jspsych/plugin-webgazer-calibrate';
Example¶
Because the eye tracking plugins need to be used in conjunction with each other, please see the example on the eye tracking overview page for an integrated example.