This script allows GMs to set up tokens on maps' GM layer to create radioactive areas. Characters can be given a 'hasGeigerCounter' attribute to alert them how many rads/s they're taking when they enter a radioactive area. If they don't have a Geiger Counter, only the GM is alerted. /**
* This script allows the GM to dynamically create radioactive areas in their
* maps. Characters that have Geiger counters will be alerted how many rads
* they are taking.
*
* To create a radioactive source object:
* 1) Create a token representing the source on the GM layer.
* 2) Set that token's 'radioactive' status marker to on.
* 3) Set its aura1 radius to the distance at which characters will start
* taking rads from it.
* 4) Set the bar1 value to amount of rads/s characters will take at the edge
* of its aura.
* 5) Set the bar1 max value to the maximum amount of rads/s characters can take
* from it.
*
* To give a player a Geiger counter:
* 1) Give them a 'hasGeigerCounter' attribute.
* 2) Set the attribute to 'true'.
*
* If a character moves in a radioactive area and they have a Geiger counter,
* their Geiger counter will alert everyone how many rads/s they are taking.
* If a character moves in a radioactive area and they don't have a Geiger
* counter, only the GM will be alerted how many rads/s they are taking.
*/
var GeigerCounter = (function() {
/**
* Computes the apparent brightness of some object, given distance from it
* and the object's luminosity.
* @param {number} distance
* @param {number} luminosity
* @return {number}
*/
function getBrightness(distance, luminosity) {
return luminosity/(4*Math.PI*distance*distance);
}
/**
* Computes the luminosity of some object, given distance from it and the
* apparent brightness of that object at that distance.
* @param {number} distance
* @param {number} brightness
* @return {number}
*/
function getLuminosity(distance, brightness) {
return brightness*4*Math.PI*distance*distance;
}
/**
* Gets the unit scale for an object's page.
* @param {graphic} The graphic whose page to get the scale for.
* @return {number}
*/
function _getPageScale(obj) {
var page = findObjs({
_type: 'page',
_id: obj.get('_pageid')
})[0];
return page.get('scale_number');
}
/**
* Gets all the tokens representing radioactive sources on the same map
* that some other graphic is on.
* @param {graphic} The graphic whose page to use.
* @return {graphic[]}
*/
function getRadioactiveTokens(obj) {
return findObjs({
_pageid: obj.get('_pageid'),
_type: 'graphic',
layer: 'gmlayer',
status_radioactive: true
});
}
/**
* Gets the amount of rads an object is taking from a radioactive token.
* @param {graphic} A graphic representing a character
* @param {graphic} A gmlayer graphic representing a radioactive source.
* @return {int}
*/
function getRads(obj, radToken) {
var maxDist = parseInt(radToken.get('aura1_radius'));
var minRads = parseInt(radToken.get('bar1_value'));
var maxRads = parseInt(radToken.get('bar1_max'));
if(!maxDist || !minRads || !maxRads)
return 0;
var x1 = obj.get('left');
var y1 = obj.get('top');
var x2 = radToken.get('left');
var y2 = radToken.get('top');
var distance = Math.sqrt((x1-x2)*(x1-x2) + (y1-y2)*(y1-y2));
distance = distance/70*_getPageScale(obj);
if(distance === 0)
return parseInt(maxRads);
if(distance > maxDist)
return 0;
var luminosity = getLuminosity(maxDist, minRads);
var brightness = getBrightness(distance, luminosity);
return Math.min(maxRads, brightness);
}
/**
* Checks if a character token has a geiger counter.
* @param {graphic} A graphic representing a character.
* @return {boolean}
*/
function hasGeigerCounter(obj) {
var charId = obj.get('represents');
if(!charId)
return false;
var geigerAttr = findObjs({
_type: 'attribute',
_characterid: charId,
name: 'hasGeigerCounter'
})[0];
return geigerAttr && geigerAttr.get('current');
}
on('change:graphic', function(obj) {
// Only handle this script if the moved object represents a
// player character.
if(obj.get('represents')) {
var character = findObjs({
_type: 'character',
_id: obj.get('represents')
})[0].get('name');
var radTokens = getRadioactiveTokens(obj);
var rads = 0;
// Get the total number of rads/s the character is taking on their
// page from all radioactive sources.
_.each(radTokens, function(radToken) {
if(obj === radToken)
return;
rads += getRads(obj, radToken);
});
// Round the total up for display.
rads = Math.ceil(rads);
if(rads) {
// If the player has a Geiger counter, let everyone know that
// they are taking rads.
if(hasGeigerCounter(obj))
sendChat('☢', character + '\'s Geiger counter is ' +
'clicking at ' + rads + ' rads/s.');
// Otherwise, let only the GM know that they are taking rads.
else
sendChat('☢', '/w GM ' + character + 'is taking ' +
rads + ' rads/s.');
}
}
});
// Expose the public functions as an API of this module.
return {
getBrightness: getBrightness,
getLuminosity: getLuminosity,
getRadioactiveTokens: getRadioactiveTokens,
getRads: getRads,
hasGeigerCounter: hasGeigerCounter
};
})(); Until it is merged into the upstream repo, you can check out the script from my fork here: <a href="https://github.com/Cazra/roll20-api-scripts/tree/m" rel="nofollow">https://github.com/Cazra/roll20-api-scripts/tree/m</a>... Demo:
