CanvasRenderingContext2D.isPointInStroke()

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The CanvasRenderingContext2D.isPointInStroke() method of the Canvas 2D API reports whether or not the specified point is inside the area contained by the stroking of a path.

Syntax

boolean ctx.isPointInStroke(x, y);
boolean ctx.isPointInStroke(path, x, y);

Parameters

x
The X coordinate of the point to check.
y
The Y coordinate of the point to check.
path
A Path2D path to use.

Return value

Boolean
A Boolean, which is true if the point is inside the area contained by the stroking of a path, otherwise false.

Examples

Using the isPointInStroke method

This is just a simple code snippet which uses the isPointInStroke method to check if a point is inside the area contained by the stroking of a path.

HTML

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

JavaScript

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

ctx.rect(10, 10, 100, 100);
ctx.stroke();
console.log(ctx.isPointInStroke(10, 10)); // true

Edit the code below, see your changes update live in the canvas and watch for loggings in your console:

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.rect(10, 10, 100, 100);
ctx.stroke();
console.log(ctx.isPointInStroke(10, 10)); // true</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

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

Browser compatibility

Update compatibility data on GitHub
DesktopMobile
ChromeEdgeFirefoxInternet ExplorerOperaSafariAndroid webviewChrome for AndroidEdge MobileFirefox for AndroidOpera for AndroidiOS SafariSamsung Internet
Basic supportChrome Full support YesEdge No support NoFirefox Full support YesIE No support NoOpera Full support YesSafari Full support YesWebView Android Full support YesChrome Android Full support YesEdge Mobile Full support YesFirefox Android Full support YesOpera Android Full support YesSafari iOS Full support YesSamsung Internet Android Full support Yes
Path parameterChrome Full support YesEdge Full support YesFirefox Full support 31IE No support NoOpera Full support YesSafari No support NoWebView Android ? Chrome Android ? Edge Mobile Full support YesFirefox Android Full support 31Opera Android ? Safari iOS ? Samsung Internet Android ?

Legend

Full support  
Full support
No support  
No support
Compatibility unknown  
Compatibility unknown

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, nmve
最終更新者: fscholz,