javascript
/
tentone.escher.js
mirror of https://github.com/tentone/escher.js.git


			
							123456789101112131415161718192021222324252627282930313233343536373839404142434445464748495051525354555657585960616263646566676869707172737475767778798081828384858687888990919293949596979899100101102103104105106107108109110111112113114115116117118119120121122123124125126127128129130131132133134135136137138139140141142143144145146147148149150151152153154155156157158159160161162163164165166167168169170171172173174175176177178179180181182183184185186187188189190191192193194195196197198199200201202203204205206207
							<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="utf-8">
    <title>JSDoc: Source: Viewport.js</title>

    <script src="scripts/prettify/prettify.js"> </script>
    <script src="scripts/prettify/lang-css.js"> </script>
    <!--[if lt IE 9]>
      <script src="//html5shiv.googlecode.com/svn/trunk/html5.js"></script>
    <![endif]-->
    <link type="text/css" rel="stylesheet" href="styles/prettify-tomorrow.css">
    <link type="text/css" rel="stylesheet" href="styles/jsdoc-default.css">
</head>

<body>

<div id="main">

    <h1 class="page-title">Source: Viewport.js</h1>

    
    <section>
        <article>
            <pre class="prettyprint source linenums"><code>import {Vector2} from "./math/Vector2.js";
import {Matrix} from "./math/Matrix.js";
import {UUID} from "./math/UUID.js";

/**
 * Viewport defines the user view into the content being rendered, similar to a camera it defines the size of the content, rotation and position of the content.
 *
 * The viewport can be moved, rotated and scaled to navigate the virtual canvas.
 *
 * @class
 * @param {Element} canvas Canvas DOM element where the viewport is being rendered.
 */
function Viewport(canvas)
{
	/**
	 * UUID of the object.
	 * 
	 * @type {string}
	 */
	this.uuid = UUID.generate(); 

	/**
	 * Canvas DOM element where the viewport is being rendered.
	 * 
	 * @type {Element}
	 */
	this.canvas = canvas;

	/**
	 * Position of the viewport.
	 * 
	 * @type {Vector2}
	 */
	this.position = new Vector2(0, 0);
	
	/**
	 * Center point of the viewport. Relative to the size of the canvas.
	 * 
	 * Rotation and zoom is applied relative to this point.
	 * 
	 * @type {Vector2}
	 */
	this.center = new Vector2(0, 0);

	/**
	 * Scale of the object.
	 * 
	 * @type {number}
	 */
	this.scale = 1.0

	/**
	 * Rotation of the object relative to its center.
	 * 
	 * @type {number}
	 */
	this.rotation = 0.0;

	/**
	 * Local transformation matrix applied to the object.
	 * 
	 * @type {Matrix}
	 */
	this.matrix = new Matrix();

	/**
	 * Inverse of the local transformation matrix.
	 * 
	 * Used to transform points from local to global coordinates.
	 * 
	 * @type {Matrix}
	 */
	this.inverseMatrix = new Matrix();

	/**
	 * If true the matrix is updated before rendering the object.
	 * 
	 * Disable this if you want to update the matrix manually.
	 * 
	 * @type {boolean}
	 */
	this.matrixNeedsUpdate = true;

	/**
	 * Flag to indicate if the viewport should move when scaling.
	 *
	 * For some application its easier to focus the target if the viewport moves to the pointer location while scaling.
	 */
	this.centerOnPointer = false;

	/**
	 * Value of the initial point of rotation if the viewport is being rotated.
	 *
	 * Is set to null when the viewport is not being rotated.
	 */
	this.rotationPoint = null;
}

/**
 * Calculate and update the viewport transformation matrix.
 *
 * Also updates the inverse matrix of the viewport.
 */
Viewport.prototype.updateMatrix = function()
{
	if(this.matrixNeedsUpdate)
	{
		this.matrix.m = [1, 0, 0, 1, this.position.x , this.position.y];
		
		if(this.center.x !== 0.0 || this.center.y !== 0.0) {
			this.matrix.multiply(new Matrix([1, 0, 0, 1, this.center.x, this.center.y]));
		}

		if(this.rotation !== 0.0)
		{		
			var c = Math.cos(this.rotation);
			var s = Math.sin(this.rotation);
			this.matrix.multiply(new Matrix([c, s, -s, c, 0, 0]));
		}

		if(this.scale !== 1.0)
		{
			this.matrix.multiply(new Matrix([this.scale, 0, 0, this.scale, 0, 0]));
		}

		if(this.center.x !== 0.0 || this.center.y !== 0.0) {
			this.matrix.multiply(new Matrix([1, 0, 0, 1, -this.center.x, -this.center.y]));
		}

		this.inverseMatrix = this.matrix.getInverse();
		this.matrixNeedsUpdate = false;
	}
};

/**
 * Center the viewport relative to a object.
 *
 * The position of the object is used a central point, this method does not consider "box" attributes or other strucures in the object.
 *
 * Uses the object's local transformation matrix and the canvas size to calculate the new position of the viewport.
 * 
 * @param {Object2D} object Object to be centered on the viewport.
 * @param {Element} canvas Canvas element where the image is drawn.
 */
Viewport.prototype.centerObject = function(object, canvas)
{
	var position = object.globalMatrix.transformPoint(new Vector2());
	position.multiplyScalar(-this.scale);
	position.x += canvas.width / 2;
	position.y += canvas.height / 2;

	this.position.copy(position);
	this.matrixNeedsUpdate = true;
};

export {Viewport};
</code></pre>
        </article>
    </section>


</div>

<nav>
    <h2><a href="index.html">Home</a></h2><h3>Classes</h3><ul><li><a href="AnimationTimer.html">AnimationTimer</a></li><li><a href="BarGraph.html">BarGraph</a></li><li><a href="BezierCurve.html">BezierCurve</a></li><li><a href="Box.html">Box</a></li><li><a href="Box2.html">Box2</a></li><li><a href="BoxMask.html">BoxMask</a></li><li><a href="Circle.html">Circle</a></li><li><a href="ColorStyle.html">ColorStyle</a></li><li><a href="DOM.html">DOM</a></li><li><a href="EventManager.html">EventManager</a></li><li><a href="FileUtils.html">FileUtils</a></li><li><a href="Gauge.html">Gauge</a></li><li><a href="GradientColorStop.html">GradientColorStop</a></li><li><a href="GradientStyle.html">GradientStyle</a></li><li><a href="Graph.html">Graph</a></li><li><a href="Helpers.html">Helpers</a></li><li><a href="Image.html">Image</a></li><li><a href="Key.html">Key</a></li><li><a href="Line.html">Line</a></li><li><a href="LinearGradientStyle.html">LinearGradientStyle</a></li><li><a href="Mask.html">Mask</a></li><li><a href="Matrix.html">Matrix</a></li><li><a href="MultiLineText.html">MultiLineText</a></li><li><a href="Node.html">Node</a></li><li><a href="NodeConnector.html">NodeConnector</a></li><li><a href="NodeGraph.html">NodeGraph</a></li><li><a href="NodeSocket.html">NodeSocket</a></li><li><a href="Object2D.html">Object2D</a></li><li><a href="Path.html">Path</a></li><li><a href="Pattern.html">Pattern</a></li><li><a href="PatternStyle.html">PatternStyle</a></li><li><a href="PieChart.html">PieChart</a></li><li><a href="Pointer.html">Pointer</a></li><li><a href="QuadraticCurve.html">QuadraticCurve</a></li><li><a href="RadialGradientStyle.html">RadialGradientStyle</a></li><li><a href="Renderer.html">Renderer</a></li><li><a href="RoundedBox.html">RoundedBox</a></li><li><a href="ScatterGraph.html">ScatterGraph</a></li><li><a href="Style.html">Style</a></li><li><a href="Text.html">Text</a></li><li><a href="UUID.html">UUID</a></li><li><a href="Vector2.html">Vector2</a></li><li><a href="Viewport.html">Viewport</a></li><li><a href="ViewportControls.html">ViewportControls</a></li></ul><h3>Global</h3><ul><li><a href="global.html#writeFile">writeFile</a></li></ul>
</nav>

<br class="clear">

<footer>
    Documentation generated by <a href="https://github.com/jsdoc/jsdoc">JSDoc 3.6.11</a> on Sat Sep 17 2022 14:24:36 GMT+0100 (Hora de verão da Europa Ocidental)
</footer>

<script> prettyPrint(); </script>
<script src="scripts/linenumber.js"> </script>
</body>
</html>