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CanvasRenderingContext2D.resetTransform

This is an experimental technology
Because this technology's specification has not stabilized, check the compatibility table for usage in various browsers. Also note that the syntax and behavior of an experimental technology is subject to change in future versions of browsers as the specification changes.

The CanvasRenderingContext2D.resetTransform() method of the Canvas 2D API resets the current transform by the identity matrix.

Syntax

void ctx.resetTransform();

Examples

Using the resetTransform method

This is just a simple code snippet which uses the resetTransform method.

HTML

<canvas id="canvas"></canvas>

JavaScript

var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');

ctx.rotate(45 * Math.PI / 180);
ctx.fillRect(70, 0, 100, 30);

// reset current transformation matrix to the identity matrix
ctx.resetTransform();

Edit the code below and see your changes update live in the canvas:

Playable code
<canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas>
<div class="playable-buttons">
  <input id="edit" type="button" value="Edit" />
  <input id="reset" type="button" value="Reset" />
</div>
<textarea id="code" class="playable-code">
ctx.rotate(45 * Math.PI / 180);
ctx.fillRect(70,0,100,30);
ctx.resetTransform();</textarea>

var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var textarea = document.getElementById("code");
var reset = document.getElementById("reset");
var edit = document.getElementById("edit");
var code = textarea.value;

function drawCanvas() {
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  eval(textarea.value);
}

reset.addEventListener("click", function() {
  textarea.value = code;
  drawCanvas();
});

edit.addEventListener("click", function() {
  textarea.focus();
})

textarea.addEventListener("input", drawCanvas);
window.addEventListener("load", drawCanvas);

Polyfill

You can also use the CanvasRenderingContext2D.setTransform() method to reset the current transform to the identity matrix, like so:

ctx.setTransform(1, 0, 0, 1, 0, 0);

Specifications

Specification Status Comment
WHATWG HTML Living Standard
The definition of 'CanvasRenderingContext2D.resetTransform' in that specification.		 Living Standard

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support 31 36 (36) No support No support No support
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support No support No support 36.0 (36) No support No support No support

See also

Edit this page on MDN

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/resetTransform