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/*
* Aurora: https://github.com/pixelmatix/aurora
* Copyright (c) 2014 Jason Coon
*
* Portions of this code are adapted from "Attractor" in "The Nature of Code" by Daniel Shiffman: http://natureofcode.com/
* Copyright (c) 2014 Daniel Shiffman
* http://www.shiffman.net
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*/
#include "Vector2.hpp"
class Attractor {
public:
float mass; // Mass, tied to size
float G; // Gravitational Constant
PVector location; // Location
Attractor() {
location = PVector(effects.getCenterX(), effects.getCenterY());
mass = 10;
G = .5;
}
PVector attract(Boid m) {
PVector force = location - m.location; // Calculate direction of force
float d = force.mag(); // Distance between objects
d = constrain(d, 5.0, 32.0); // Limiting the distance to eliminate "extreme" results for very close or very far objects
force.normalize(); // Normalize vector (distance doesn't matter here, we just want this vector for direction)
float strength = (G * mass * m.mass) / (d * d); // Calculate gravitational force magnitude
force *= strength; // Get force vector --> magnitude * direction
return force;
}
};
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