HTML5 CANVAS draw image

Question

Here is my question

I kind of not understand what is the sx and sy is for in below function

context.drawImage(Image, sx, sy, sw, sh, dx, dy, dw, dh);

<

Answer 1

(sx, sy) is the top-left corner of the source rectangle (within the source image) which are going to draw to the destination. Take a look at the diagram below:

[Reference]

sx=0,sy=0 is different from sx=300,sy=300 because they refer to different source rectangles.