[Feature] Different width/height for canvas and canvas style

[shunia]

Motivation

The canvas logical size, which is different than it's dom size(computed css style size).

I want to have them seperated so that I could set the logical size to the original size of the rendering texture, so that I could get the image data in the original resolution, but still be able to change the canvas dom size to fit the design.

Detailed Description

For now when calling setSize on a view, the logical size and the dom size are changed altogether, for example if I want to maintain the original resolution to 512512, I would want to call setSize(512, 512), but then the canvas dom size changed to 512512 too, which is not expected.

[finetjul]

I guess that's a fine request. Feel free to create a PR.
It would however have to come with a good interactive example because it is a tricky subjects that many face and got wrong.