105 lines
3.8 KiB
TypeScript
105 lines
3.8 KiB
TypeScript
/// <reference path="Serializable.ts"/>
|
|
|
|
module TS.SpaceTac.Game {
|
|
// Find the nearest intersection between a line and a circle
|
|
// Circle is supposed to be centered at (0,0)
|
|
// Nearest intersection to (x1,y1) is returned
|
|
function intersectLineCircle(x1: number, y1: number, x2: number, y2: number, r: number): [number, number] {
|
|
// See http://mathworld.wolfram.com/Circle-LineIntersection.html
|
|
var dx = x2 - x1;
|
|
var dy = y2 - y1;
|
|
var dr = Math.sqrt(dx * dx + dy * dy);
|
|
var d = x1 * y2 - x2 * y1;
|
|
var delta = r * r * dr * dr - d * d;
|
|
|
|
var rx = (d * dy - dx * Math.sqrt(delta)) / (dr * dr);
|
|
var ry = (-d * dx - dy * Math.sqrt(delta)) / (dr * dr);
|
|
return [rx, ry];
|
|
}
|
|
|
|
// Target for a capability
|
|
// This could be a location in space, or a ship
|
|
export class Target extends Serializable {
|
|
// Coordinates of the target
|
|
x: number;
|
|
y: number;
|
|
|
|
// If the target is a ship, this attribute will be set
|
|
ship: Ship;
|
|
|
|
// Standard constructor
|
|
constructor(x: number, y: number, ship: Ship) {
|
|
super();
|
|
|
|
this.x = x;
|
|
this.y = y;
|
|
this.ship = ship;
|
|
}
|
|
|
|
// Constructor to target a single ship
|
|
static newFromShip(ship: Ship): Target {
|
|
return new Target(ship.arena_x, ship.arena_y, ship);
|
|
}
|
|
|
|
// Constructor to target a location in space
|
|
static newFromLocation(x: number, y: number): Target {
|
|
return new Target(x, y, null);
|
|
}
|
|
|
|
// Get distance to another target
|
|
getDistanceTo(other: Target): number {
|
|
var dx = other.x - this.x;
|
|
var dy = other.y - this.y;
|
|
return Math.sqrt(dx * dx + dy * dy);
|
|
}
|
|
|
|
// Get the normalized angle, in radians, to another target
|
|
getAngleTo(other: Target): number {
|
|
var dx = other.x - this.x;
|
|
var dy = other.y - this.y;
|
|
return Math.atan2(dy, dx);
|
|
}
|
|
|
|
// Check if a target is in range from a specific point
|
|
isInRange(x: number, y: number, radius: number): boolean {
|
|
var dx = this.x - x;
|
|
var dy = this.y - y;
|
|
var length = Math.sqrt(dx * dx + dy * dy);
|
|
return (length <= radius);
|
|
}
|
|
|
|
// Constraint a target, to be in a given range from a specific point
|
|
// May return the original target if it's already in radius
|
|
constraintInRange(x: number, y: number, radius: number): Target {
|
|
var dx = this.x - x;
|
|
var dy = this.y - y;
|
|
var length = Math.sqrt(dx * dx + dy * dy);
|
|
if (length <= radius) {
|
|
return this;
|
|
} else {
|
|
var factor = radius / length;
|
|
return Target.newFromLocation(x + dx * factor, y + dy * factor);
|
|
}
|
|
}
|
|
|
|
// Force a target to stay out of a given circle
|
|
// If the target is in the circle, it will be moved to the nearest intersection between targetting line
|
|
// and the circle
|
|
// May return the original target if it's already out of the circle
|
|
moveOutOfCircle(circlex: number, circley: number, radius: number, sourcex: number, sourcey: number): Target {
|
|
var dx = this.x - circlex;
|
|
var dy = this.y - circley;
|
|
var length = Math.sqrt(dx * dx + dy * dy);
|
|
if (length >= radius) {
|
|
// Already out of circle
|
|
return this;
|
|
} else {
|
|
// Find nearest intersection with circle
|
|
var res = intersectLineCircle(sourcex - circlex, sourcey - circley,
|
|
this.x - circlex, this.y - circley, radius);
|
|
return Target.newFromLocation(res[0] + circlex, res[1] + circley);
|
|
}
|
|
}
|
|
}
|
|
}
|