mTurk HIT Fullscreen Crosshair CSS (as Userscript)

Userscript adapatation (and improvement) of code found at https://codepen.io/michaelsboost/pen/fnizu - applied to mTurk.

您需要先安装一个扩展,例如 篡改猴Greasemonkey暴力猴,之后才能安装此脚本。

You will need to install an extension such as Tampermonkey to install this script.

您需要先安装一个扩展,例如 篡改猴暴力猴,之后才能安装此脚本。

您需要先安装一个扩展,例如 篡改猴Userscripts ,之后才能安装此脚本。

您需要先安装一款用户脚本管理器扩展,例如 Tampermonkey,才能安装此脚本。

您需要先安装用户脚本管理器扩展后才能安装此脚本。

(我已经安装了用户脚本管理器,让我安装!)

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展,比如 Stylus,才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

您需要先安装一款用户样式管理器扩展后才能安装此样式。

(我已经安装了用户样式管理器,让我安装!)

// ==UserScript==
// @name         mTurk HIT Fullscreen Crosshair CSS (as Userscript)
// @namespace    salembeats
// @version      1.7
// @description  Userscript adapatation (and improvement) of code found at https://codepen.io/michaelsboost/pen/fnizu - applied to mTurk.
// @author       Cuyler Stuwe (salembeats) using code adapted from Michael Schwartz
// @include      *
// @grant        none
// ==/UserScript==

// *****************************************************************************

function isNotMturkFrame() {
	return !(
		window !== window.top &&
		document.referrer.includes("worker.mturk.com/projects/")
	);
}

if(isNotMturkFrame()) {return;}

// *****************************************************************************

// Just here for faster autocomplete suggestions.

const CROSSHAIR_STYLES = {
	DOTTED: "dotted",
	DASHED: "dashed",
	SOLID: "solid"
};

const CROSSHAIR_COLORS = {
	BLACK: "black",
	RED: "red",
	GREEN: "green",
	BLUE: "blue"
};

// *****************************************************************************
// SET UP YOUR CROSSHAIR STYLE HERE.
// *****************************************************************************

const CROSSHAIR_THICKNESS_PX                    = 1;
const CROSSHAIR_STYLE                           = CROSSHAIR_STYLES.DOTTED;
const CROSSHAIR_COLOR                           = CROSSHAIR_COLORS.RED;
const SHOULD_MODIFY_POINTER_TO_CROSSHAIR_CURSOR = true;

// *****************************************************************************

document.body.insertAdjacentHTML("beforeend", `
<div id="crosshair-h" class="hair"></div>
<div id="crosshair-v" class="hair"></div>
`);

document.head.insertAdjacentHTML("beforeend", `
<style>

* {

    ${SHOULD_MODIFY_POINTER_TO_CROSSHAIR_CURSOR ? "cursor: crosshair !important;" : ""}

}

#crosshair-h {

    width: 100%;

}

#crosshair-v {

    height: 100%;

}

.hair {

    position: fixed;
    top:0; left:0;

    margin-top: 0px; /* The offset here by the original author made zero sense. */
    margin-left: 0px; /* The offset here by the original author made zero sense. */

    background: transparent;

    border-top: ${CROSSHAIR_THICKNESS_PX}px ${CROSSHAIR_STYLE} ${CROSSHAIR_COLOR};
    border-left: ${CROSSHAIR_THICKNESS_PX}px ${CROSSHAIR_STYLE} ${CROSSHAIR_COLOR};

    pointer-events: none;

    z-index: ${Number.MAX_SAFE_INTEGER};

}
</style>
`);

let cH = document.getElementById('crosshair-h'),
	cV = document.getElementById('crosshair-v');

document.addEventListener("mousemove", e => {
	cH.style.top  = e.clientY + "px";
	cV.style.left = e.clientX + "px";
});