W3cubDocs

/DOM

CanvasRenderingContext2D.setTransform

The CanvasRenderingContext2D.setTransform() method of the Canvas 2D API resets (overrides) the current transformation to the identity matrix and then invokes a transformation described by the arguments of this method.

See also the transform() method, which does not override the current transform matrix and multiplies it with a given one.

Syntax

void ctx.setTransform(a, b, c, d, e, f);

The transformation matrix is described by: [acebdf001]\left[ \begin{array}{ccc} a & c & e \\ b & d & f \\ 0 & 0 & 1 \end{array} \right]

Parameters

a (m11)
Horizontal scaling.
b (m12)
Horizontal skewing.
c (m21)
Vertical skewing.
d (m22)
Vertical scaling.
e (dx)
Horizontal moving.
f (dy)
Vertical moving.

Examples

Using the setTransform method

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

HTML

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

JavaScript

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

ctx.setTransform(1, 1, 0, 1, 0, 0);
ctx.fillRect(0, 0, 100, 100);

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.setTransform(1,1,0,1,0,0);
ctx.fillRect(0,0,100,100);</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);

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes 12 Yes Yes Yes Yes
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes Yes Yes Yes Yes Yes Yes

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/setTransform