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CanvasRenderingContext2D.clip()

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The CanvasRenderingContext2D.clip() method of the Canvas 2D API turns the path currently being built into the current clipping path.

Syntax

void ctx.clip();
void ctx.clip(fillRule);
void ctx.clip(path, fillRule);

Parameters

fillRule
The algorithm by which to determine if a point is inside a path or outside a path.
Possible values:
path
A Path2D path to clip.

Examples

Using the clip method

This is just a simple code snippet which uses the clip method to create a clipping region.

HTML

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

JavaScript

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

// Create clipping region
ctx.arc(100, 100, 75, 0, Math.PI*2, false);
ctx.clip();

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.arc(100, 100, 75, 0, Math.PI*2, false);
ctx.clip();
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);

Note: Be aware that clip() only works with shapes added to the path; it doesn't work with shape primitives such as rectangles created with fillRect(). In this case you'd have to use rect() to draw a rectangular path shape to be clipped.

Specifications

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

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) (Yes) (Yes) (Yes) (Yes)
Path parameter ? 31 (31) Not supported ? Not supported
Feature Android Chrome for Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support (Yes) (Yes) (Yes) (Yes) (Yes) (Yes)
Path parameter ? ? 31.0 (31) ? ? ?

See also

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