'use strict';
var Thing = require('./thing.js');
/**
* @class Line
* @augments Thing
* @param {number} x1 - x coordinate of starting point of line.
* @param {number} y1 - y coordinate of starting point of line.
* @param {number} x2 - x coordinate of end point of line.
* @param {number} y2 - y coordinate of end point of line.
*/
function Line(x1, y1, x2, y2) {
if (arguments.length !== 4) {
throw new Error(
'You should pass exactly 4 argument to <span ' +
'class="code">new Line(x1, y1, x2, y2)</span>'
);
}
if (
typeof x1 !== 'number' ||
typeof y1 !== 'number' ||
typeof x2 !== 'number' ||
typeof y2 !== 'number'
) {
throw new TypeError(
'You must pass 4 numbers to <span class="code">' +
'new Line(x1, y1, x2, y2)</span>. Make sure each parameter you' +
'are passing is a number.'
);
}
if (!isFinite(x1) || !isFinite(y1) || !isFinite(x2) || !isFinite(y2)) {
throw new TypeError(
'One or more of the values you passed to <span ' +
'class="code">new Line(x1, y1, x2, y2)</span> is an illegal ' +
'number. Did you forget the parentheses in <span class="code">' +
'getWidth()</span> or <span class="code">getHeight()</span>? Or ' +
'did you perform a calculation on a variable that is not a ' +
'number?'
);
}
Thing.call(this);
this.x1 = x1;
this.y1 = y1;
this.x2 = x2;
this.y2 = y2;
this.lineWidth = 2;
this.type = 'Line';
}
Line.prototype = new Thing();
Line.prototype.constructor = Line;
/**
* Sets the color of a line.
*
* @param {Color} color - Sets the color of the line.
*/
Line.prototype.setColor = function(color) {
if (arguments.length !== 1) {
throw new Error(
'You should pass exactly 1 argument to <span ' + 'class="code">setColor(color)</span>.'
);
}
if (color === undefined) {
throw new TypeError('Invalid color');
}
this.stroke = color;
};
/**
* Gets the color of a line.
*
* @returns {Color} Color of the line.
*/
Line.prototype.getColor = function() {
return this.stroke;
};
/**
* Draws the line in the canvas.
*
* @param {CodeHSGraphics} __graphics__ - Instance of the __graphics__ module.
*/
Line.prototype.draw = function(__graphics__) {
var context = __graphics__.getContext();
// http://stackoverflow.com/questions/17125632/html5-canvas-rotate-object-without-moving-coordinates
context.save();
context.fillStyle = this.color.toString();
context.beginPath();
context.strokeStyle = this.stroke.toString();
context.lineWidth = this.lineWidth;
var rotatedPoints = getRotatedPoints(this.x1, this.y1, this.x2, this.y2, this.rotation);
context.moveTo(rotatedPoints[0], rotatedPoints[1]);
context.lineTo(rotatedPoints[2], rotatedPoints[3]);
context.closePath();
context.stroke();
context.restore();
};
/**
* Gets the new points based on their rotated values.
*
*/
/**
* Gets the new points based on their rotated values.
*
* @param {number} x1 X coordinate of start point
* @param {number} y1 Y coordinate of start point
* @param {number} x2 X coordinate of end point
* @param {number} y2 Y Coordinate of end point
* @param {number} rotation radians rotated (Expected in radians)
* @return {array} List of coordinates of both points.
*/
var getRotatedPoints = function(x1, y1, x2, y2, rotation) {
var midX = (x1 + x2) / 2;
var midY = (y1 + y2) / 2;
var sinAngle = Math.sin(rotation);
var cosAngle = Math.cos(rotation);
var newX;
var newY;
// Rotate point 1
x1 -= midX;
y1 -= midY;
newX = x1 * cosAngle - y1 * sinAngle;
newY = x1 * sinAngle + y1 * cosAngle;
x1 = newX + midX;
y1 = newY + midY;
// Rotate point 2
x2 -= midX;
y2 -= midY;
newX = x2 * cosAngle - y2 * sinAngle;
newY = x2 * sinAngle + y2 * cosAngle;
x2 = newX + midX;
y2 = newY + midY;
return [x1, y1, x2, y2];
};
/**
* Checks if a given point is contained in the line.
*
* @param {number} x - x coordinate of the point being tested.
* @param {number} y - y coordinate of the point being tested.
*/
Line.prototype.containsPoint = function(x, y) {
var slope = (this.y2 - this.y1) / (this.x2 - this.x1);
var betweenXs = (this.x1 <= x && x <= this.x2) || (this.x2 <= x && x <= this.x1);
var betweenYs = (this.y1 <= y && y <= this.y2) || (this.y2 <= y && y <= this.y1);
return (
Math.abs(slope * (x - this.x1) - (y - this.y1)) <= this.lineWidth && betweenXs && betweenYs
);
};
/**
* Returns the width of the line.
*
* @returns {number} The width of the line.
*/
Line.prototype.getWidth = function() {
return this.width;
};
/**
* Returns the height of the line.
*
* @returns {number} The width of the line.
*/
Line.prototype.getHeight = function() {
return this.height;
};
/**
* Sets the width of the line.
*
* @param {number} width - The resulting width of the line.
*/
Line.prototype.setLineWidth = function(width) {
if (arguments.length !== 1) {
throw new Error(
'You should pass exactly 1 argument to <span ' + 'class="code">setLineWidth</span>'
);
}
if (typeof width !== 'number' || !isFinite(width)) {
throw new TypeError(
'You must pass a finite number to <span class=' +
'"code">setLineWidth(width)</span>. Did you perform a ' +
'calculation on a variable that is not a number?'
);
}
this.lineWidth = width;
};
/**
* Sets the *starting* point of the line.
*
* @param {number} x - The x coordinate of the resulting ending point.
* @param {number} y - The y coordinate of the resulting ending point.
*/
Line.prototype.setStartpoint = function(x, y) {
if (arguments.length !== 2) {
throw new Error(
'You should pass exactly 2 arguments to <span ' +
'class="code">setStartpoint(x, y)</span>'
);
}
if (typeof x !== 'number' || !isFinite(x)) {
throw new TypeError(
'Invalid value for x-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setStartpoint(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
if (typeof y !== 'number' || !isFinite(y)) {
throw new TypeError(
'Invalid value for y-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setStartpoint(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
this.setPosition(x, y);
};
/**
* Sets the *starting* point of the line.
*
* @param {number} x - The x coordinate of the resulting starting point.
* @param {number} y - The y coordinate of the resulting starting point.
*/
Line.prototype.setPosition = function(x, y) {
if (arguments.length !== 2) {
throw new Error(
'You should pass exactly 2 arguments to <span ' +
'class="code">setPosition(x, y)</span>'
);
}
if (typeof x !== 'number' || !isFinite(x)) {
throw new TypeError(
'Invalid value for x-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setPosition(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
if (typeof y !== 'number' || !isFinite(y)) {
throw new TypeError(
'Invalid value for y-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setPosition(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
this.x1 = x;
this.y1 = y;
};
/**
* Sets the *ending* point of the line.
*
* @param {number} x - The x coordinate of the resulting ending point.
* @param {number} y - The y coordinate of the resulting ending point.
*/
Line.prototype.setEndpoint = function(x, y) {
if (arguments.length !== 2) {
throw new Error(
'You should pass exactly 2 arguments to <span ' +
'class="code">setEndpoint(x, y)</span>'
);
}
if (typeof x !== 'number' || !isFinite(x)) {
throw new TypeError(
'Invalid value for x-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setEndpoint(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
if (typeof y !== 'number' || !isFinite(y)) {
throw new TypeError(
'Invalid value for y-coordinate. ' +
'Make sure you are passing finite numbers to <span ' +
'class="code">setEndpoint(x, y)</span>. Did you ' +
'forget the parentheses in <span class="code">getWidth()</span> ' +
'or <span class="code">getHeight()</span>? Or did you perform a ' +
'calculation on a variable that is not a number?'
);
}
this.x2 = x;
this.y2 = y;
};
/**
* Moves the entire line.
*
* @param {number} dx - The change in x coordinate of both starting and ending points.
* @param {number} dy - The change in y coordinate of both starting and ending points.
*/
Line.prototype.move = function(dx, dy) {
if (arguments.length !== 2) {
throw new Error(
'You should pass exactly 2 arguments to <span ' + 'class="code">move</span>'
);
}
if (typeof dx !== 'number' || !isFinite(dx)) {
throw new TypeError(
'Invalid number passed for <span class="code">' +
'dx</span>. Make sure you are passing finite numbers to <span ' +
'class="code">move(dx, dy)</span>'
);
}
if (typeof dy !== 'number' || !isFinite(dy)) {
throw new TypeError(
'Invalid number passed for <span class="code">' +
'dy</span>. Make sure you are passing finite numbers to <span ' +
'class="code">move(dx, dy)</span>'
);
}
this.x1 += dx;
this.y1 += dy;
this.x2 += dx;
this.y2 += dy;
};
/**
* Gets the x coordinate of the Line's start point.
*
* @returns {number} The x coordinate of the Line's start point.
*/
Line.prototype.getX = function() {
return this.x1;
};
/**
* Gets the y coordinate of the Line's start point.
*
* @returns {number} The y coordinate of the Line's start point.
*/
Line.prototype.getY = function() {
return this.y1;
};
/**
* Gets the x coordinate of the Line's start point.
*
* @returns {number} The x coordinate of the Line's start point.
*/
Line.prototype.getStartX = function() {
return this.x1;
};
/**
* Gets the y coordinate of the Line's start point.
*
* @returns {number} The y coordinate of the Line's start point.
*/
Line.prototype.getStartY = function() {
return this.y1;
};
/**
* Gets the x coordinate of the Line's end point.
*
* @returns {number} The x coordinate of the Line's end point.
*/
Line.prototype.getEndX = function() {
return this.x2;
};
/**
* Gets the y coordinate of the Line's end point.
*
* @returns {number} The y coordinate of the Line's end point.
*/
Line.prototype.getEndY = function() {
return this.y2;
};
module.exports = Line;