drawImage
Summary
Draws the specified image onto the canvas. Can be called in three ways; see Notes.
Method of apis/canvas/CanvasRenderingContext2Dapis/canvas/CanvasRenderingContext2D
Syntax
var object = object.drawImage(image, sx, sy, sw, sh, dx, dy, dw, dh);
Parameters
image
- Data-type
- DOM Node
An image, canvas, or video element of the pattern to use.
sx
- Data-type
- Number
The horizontal starting value (x), in CSS pixels, relative to the source image.
sy
- Data-type
- Number
The vertical starting value (y), in CSS pixels, relative to the source image.
sw
- Data-type
- Number
The width of the source image, in CSS pixels, to draw onto the canvas.
sh
- Data-type
- Number
The height of the source image, in CSS pixels, to draw onto the canvas.
dx
- Data-type
- Number
The horizontal (x) value, in CSS pixels, where to place the image on the canvas.
dy
- Data-type
- Number
The vertical (y) value, in CSS pixels, where to place the image on the canvas.
dw
- Data-type
- Number
The destination width value, in CSS pixels, to use when drawing the image to the canvas.
dh
- Data-type
- Number
The destination height value, in CSS pixels, to use when drawing the image to the canvas.
Return Value
Returns an object of type DOM NodeDOM Node
Type: HRESULT
This method can return one of these values.
Return code | Description |
---|---|
S_OK | The operation completed successfully. |
TypeMismatchError | The image parameter is not an img object, canvas element, or video element. |
InvalidStateError _ERR | The image parameter does not contain image data. |
IndexSizeError | The numeric arguments are not valid (for example, the destination is a 0x0 rectangle). |
SecurityError | The img or video element is not of the same origin or domain as the document that owns the canvas element. |
Examples
This example uses the most straightforward syntax, simply drawing an existing page image onto the canvas.
<img id="clock" src="clock.jpg" width="200" height="100" style="visibility:hidden"/>
<canvas id="myCanvas" width="300" height="150" style="border:1px solid blue;"></canvas>
<p>. . .</p>
<script>
var can = document.getElementById("myCanvas");
var ctxt = can.getContext("2d");
var image = document.getElementById("clock");
ctxt.drawImage(image, 10, 10);
</script>
Notes
The drawImage method provides three ways to draw an image onto a canvas, depending on how you use the optional parameters:
- drawImage(image,dx,dy) copies an image exactly to the canvas at the location that the dx and dy parameters specify.
- drawImage(image,dx,dy,dw,dh) copies an image to the canvas by using the dw and dh parameters to stretch or reduce the image. This option is similar to the size attributes on an img tag.
- drawImage(image,sx,sy,sw,sh,dx,dy,dw,dh) copies all or part of a source image to the canvas. You can place and size the destination image by using the destination parameters.
If you do not specify the dw and dh parameters, they equal the values of sw and sh. One CSS pixel in the image is treated as one unit in the canvas coordinate space.
Related specifications
- W3C HTML Canvas 2D Specification
- W3C Candidate Recommendation
Attributions
Microsoft Developer Network: Windows Internet Explorer API reference Article