[patch][CCLA] canvas renderer does not take into account the x/y/width/height attributes of a pattern fill style.

[Patrick Ruzand]

The canvas renderer does not taken into account the x/y/width/height attributes of a pattern fill style.

In the current implementation, the pattern image is created via the new Image(w,h) ctor, specifying the fillstyle with/height. However, the canvas spec. tells that the original image data must be used when creating the pattern, therefore the image scaling done in the ctor is not taken into account by the context2d (as we can see by running the dojox/gfx/tests/test_pattern.html sample with the canvas renderer enabled).

Proposed fix: the image scaling needs to be done in an temporary canvas via a call to drawImage(), and then pass this temp. canvas element to the ctx.createPattern() method. See patch attached.

Patches attached (canvas.js, test_pattern.html) submitted by Patrick Ruzand, IBM (CCLA)

[Patrick Ruzand]

modify test to add x/y offset and aspect ratio testing

[Patrick Ruzand]

fix pattern scaling and offset support

[Eugene Lazutkin]

Fixed in [23684].