Please note, this is a STATIC archive of website developer.mozilla.org from 03 Nov 2016, cach3.com does not collect or store any user information, there is no "phishing" involved.

CanvasRenderingContext2D.resetTransform()

この記事はまだボランティアによって 日本語 に翻訳されていません。ぜひ MDN に参加して翻訳を手伝ってください!

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) Not supported Not supported Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support Not supported Not supported 36.0 (36) Not supported Not supported Not supported

See also

ドキュメントのタグと貢献者

 このページの貢献者: fscholz
 最終更新者: fscholz,