I've tried to use the drawImage function of the canvas.
In the documentation (http://msdn.microsoft.com/en-us/library/ie/ff975414(v=vs.85).aspx) I thought the last two parameters are the destination point, but I guess it's not because it's not working.
Is there a way to draw image between two points without rotate it or something like this?
Thanks!
context.drawImage(
sourceImage,
sourceX, sourceY, sourceWidthToClip, sourceHeightToClip,
canvasX, canvasY, scaledWidth, scaledHeight );
In context.drawImage
the first parameter is the source image.
The next 4 parameters are the x,y,width & height rectangular sub-image to clip from that source
The last 4 parameters are the x,y,scaledWidth & scaledHeight rectangular scaled image to draw on the canvas.
Annotated drawImage:
context.drawImage(
sourceImage, // the source image to clip from
sX, // the left X position to start clipping
sY, // the top Y position to start clipping
sW, // clip this width of pixels from the source
wH, // clip this height of pixels from the source
dX, // the left X canvas position to start drawing the clipped sub-image
dY, // the top Y canvas position to start drawing the clipped sub-image
dW, // scale sW to dW and draw a dW wide sub-image on the canvas
dH // scale sH to dH and draw a dH high sub-image on the canvas
}
Visual drawImage:
![enter image description here][1]
Code example for drawImage:
var canvas=document.getElementById("canvas");
var ctx=canvas.getContext("2d");
var canvas1=document.getElementById("drawImage");
var ctx1=canvas1.getContext("2d");
var img=new Image();
img.onload=start;
img.src="https://dl.dropboxusercontent.com/u/139992952/stackoverflow/avatars.jpg";
function start(){
canvas.width=img.width;
canvas.height=img.height;
ctx.drawImage(img,0,0);
var scale=2;
canvas1.width=471/5*3;
canvas1.height=255/2*3;
ctx1.drawImage(img,
94,0,94,120,
50,50,94*scale,120*scale
);
}
body{ background-color: ivory; padding:10px; }
canvas{border:1px solid red;}
<h4>The original image</h4>
<canvas id="canvas" width=300 height=300></canvas><br>
<h4>The clipped & scaled sub-image drawn into the canvas</h4>
<canvas id="drawImage" width=300 height=300></canvas>
Example Illustration for drawImage:
[ Addition: How to control dx,dy with html range controls ]
var canvas=document.getElementById("canvas");
var ctx=canvas.getContext("2d");
var canvas1=document.getElementById("drawImage");
var ctx1=canvas1.getContext("2d");
var $dx=$('#dx');
var $dy=$('#dy');
var scale=2;
var img=new Image();
img.onload=start;
img.src="https://dl.dropboxusercontent.com/u/139992952/stackoverflow/avatars.jpg";
function start(){
canvas.width=img.width;
canvas.height=img.height;
ctx.drawImage(img,0,0);
canvas1.width=471/5*3;
canvas1.height=255/2*3;
draw();
$dx.change(function(){draw();});
$dy.change(function(){draw();});
}
function draw(){
ctx1.clearRect(0,0,canvas1.width,canvas1.height);
ctx1.drawImage(img,94,0,94,120,$dx.val(),$dy.val(),94*scale,120*scale);
}
body{ background-color: ivory; padding:10px; }
canvas{border:1px solid red;}
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>
<h4>The original image</h4>
<canvas id="canvas" width=300 height=300></canvas><br>
<h4>The clipped & scaled sub-image drawn into the canvas</h4>
dx:<input id=dx type=range min=0 max=280 value=0><br>
dy:<input id=dy type=range min=0 max=380 value=0><br>
<canvas id="drawImage" width=300 height=300></canvas>
[1]: http://i.stack.imgur.com/9paHM.jpg