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.
void ctx.setTransform(a, b, c, d, e, f);
The transformation matrix is described by:
a (m11)b (m12)c (m21)d (m22)e (dx)f (dy)setTransform methodThis is just a simple code snippet which uses the setTransform method.
<canvas id="canvas"></canvas>
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:
<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);
| Specification | Status | Comment |
|---|---|---|
| HTML Living Standard The definition of 'CanvasRenderingContext2D.setTransform' in that specification. | Living Standard |
| 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 |
CanvasRenderingContext2D
CanvasRenderingContext2D.transform()
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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/setTransform