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// how many ways can I make a point?
// 1)
function Point(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
}
Point.prototype.offset = function(tx, ty, tz) {
this.x += tx;
this.y += ty;
this.z += tz;
};
Point.prototype.add = function(point) {
this.offset(point.x, point.y, point.z);
};
Point.prototype.subtract = function(point) {
this.x = point.x;
this.y = point.y;
this.z = point.z;
};
Point.prototype.clone = function() {
return new Point(this.x, this.y, this.z);
};
var one = new Point(10, 10, 10);
// 2)
function Point(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
}
Point.prototype = {
constructor: Point,
offset: function(tx, ty, tz) {
this.x += tx;
this.y += ty;
this.z += tz;
},
add: function(point) {
this.offset(point.x, point.y, point.z);
},
subtract: function(point) {
this.x = point.x;
this.y = point.y;
this.z = point.z;
},
clone: function() {
return new Point(this.x, this.y, this.z);
}
};
var two = new Point(10, 10, 10);
// 3)
function Point(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
this.offset = function(tx, ty, tz) {
this.x += tx;
this.y += ty;
this.z += tz;
};
this.add = function(point) {
this.offset(point.x, point.y, point.z);
};
this.subtract = function(point) {
this.x = point.x;
this.y = point.y;
this.z = point.z;
};
this.clone = function() {
return new Point(this.x, this.y, this.z);
};
}
var three = new Point(10, 10, 10);
// 4)
function Point(x, y, z) {
var self = {
x: x,
y: y,
z: z,
offset: function(tx, ty, tz) {
self.x += tx;
self.y += ty;
self.z += tz;
},
add: function(point) {
self.offset(point.x, point.y, point.z);
},
subtract: function(point) {
self.x = point.x;
self.y = point.y;
self.z = point.z;
},
clone: function() {
return Point(self.x, self.y, self.z);
}
};
return self;
};
var four = Point(10, 10, 10); // note no new keyword
// 5) this is one way to use Object.create() (lots of other ways)
var Point = {
x: 0,
y: 0,
z: 0,
init: function(x, y, z) {
this.x = x;
this.y = y;
this.z = z;
return this;
},
offset: function(tx, ty, tz) {
this.x += tx;
this.y += ty;
this.z += tz;
},
add: function(point) {
this.offset(point.x, point.y, point.z);
},
subtract: function(point) {
this.x = point.x;
this.y = point.y;
this.z = point.z;
},
clone: function() {
return Object.create(Point).init(this.x, this.y, this.z);
}
};
var five = Object.create(Point).init(10, 10, 10);
// There are a bunch more ways, especially when you introduce javascript libraries. 