Fill opacity conflict with stroke opacity using Canvas

[jfgirard]

When I use CANVAS to render a Polygon, there is a case where the opacity is not well set. Its fine using SVG.

1- Fill opacity < 1
2. Stroke Opacity = 1

In this case, both fill and stroke opacity are set to the fill's one.

Current implementation:
Path.Canvas.js From Line 105

if (options.fill) {
    if (options.fillOpacity < 1) {
    ctx.globalAlpha = options.fillOpacity;
    }
    ctx.fill();
}
if (options.stroke) {
    if (options.opacity < 1) {
        ctx.globalAlpha = options.opacity;
    }
    ctx.stroke();
}

A simple fix is to add a else if for stroke:

if (options.stroke) {
    if (options.opacity < 1) {
        ctx.globalAlpha = options.opacity;
    }else if (options.fill && options.fillOpacity !== 1) {
        ctx.globalAlpha = 1;
    }
    ctx.stroke();
}

What do you think ? I'm a bit lazy to do a PR ;)

[danzel]

There is probably something wrong with my test case, but:
http://jsperf.com/globalopasictyperformance

I think we could just always set it?

[danzel]

There was something wrong with my test case, I was setting the wrong var, woops!
Fixed now, results seem to show maybe we just always set it.

[danzel]

Sent a PR to just always set them.