CanvasRenderingContext2D: resetTransform() method
The
CanvasRenderingContext2D.resetTransform()
method of the Canvas 2D API resets the current transform to the identity matrix.
Syntax
js
resetTransform()
Examples
Resetting the matrix
This example draws a rotated rectangle after modifying the matrix, and then resets the
matrix using the resetTransform()
method.
HTML
html
<canvas id="canvas"></canvas>
JavaScript
The rotate()
method rotates the
transformation matrix by 45°. The fillRect()
method draws a filled rectangle, adjusted according to that matrix.
js
const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
// Draw a rotated rectangle
ctx.rotate((45 * Math.PI) / 180);
ctx.fillRect(60, 0, 100, 30);
// Reset transformation matrix to the identity matrix
ctx.resetTransform();
Result
Continuing with a regular matrix
Whenever you're done drawing transformed shapes, you should call
resetTransform()
before rendering anything else. In this example, the first
two shapes are drawn with a skew transformation, and the last two are drawn with the
identity (regular) transformation.
HTML
html
<canvas id="canvas"></canvas>
JavaScript
js
const canvas = document.getElementById("canvas");
const ctx = canvas.getContext("2d");
// Skewed rectangles
ctx.transform(1, 0, 1.7, 1, 0, 0);
ctx.fillStyle = "gray";
ctx.fillRect(40, 40, 50, 20);
ctx.fillRect(40, 90, 50, 20);
// Non-skewed rectangles
ctx.resetTransform();
ctx.fillStyle = "red";
ctx.fillRect(40, 40, 50, 20);
ctx.fillRect(40, 90, 50, 20);
Result
The skewed rectangles are gray, and the non-skewed rectangles are red.
Polyfill
You can also use the setTransform()
method to reset the current transform to the identity matrix, like
so:
js
ctx.setTransform(1, 0, 0, 1, 0, 0);
Specifications
Specification |
---|
HTML Standard # dom-context-2d-resettransform-dev |
Browser compatibility
BCD tables only load in the browser
See also
- The interface defining this method:
CanvasRenderingContext2D