use 4 windows for drawing --line mode=edge borders

[N-R-K]

this uses similar approach to selx by using 4 windows to draw the border. using XShape extension does not work well with compositors but the 4 window method works fine.

Fixes: #76

[N-R-K]

@daltomi should this be a new mode or should it just replace the existing "edge" mode?

[daltomi]

I vote to replace edge mode with this.
edge mode has issues with some composers when shadows are activated.

The only thing that needs fixing is the following. When I have opacity enabled in the compositor, you can see the windows merging in the upper left corner.

---

I fixed it quickly with the next patch, but if you have another idea, that would be great!

diff --git a/src/selection_wind.c b/src/selection_wind.c
index 2f568d9..eb0f75a 100644
--- a/src/selection_wind.c
+++ b/src/selection_wind.c
@@ -85,7 +85,7 @@ void selectionWindDraw(void)
     struct SelectionWind *const pw = &sel->wind;
 
     XRectangle rects[4] = {
-        { sel->rect.x, sel->rect.y, opt.lineWidth, sel->rect.h }, // left
+        { sel->rect.x, sel->rect.y+opt.lineWidth, opt.lineWidth, sel->rect.h - opt.lineWidth }, // left
         { sel->rect.x, sel->rect.y, sel->rect.w, opt.lineWidth }, // top
         // right
         { sel->rect.x + sel->rect.w, sel->rect.y, opt.lineWidth, sel->rect.h },

[N-R-K]

I vote to replace edge mode with this.

Done.

When I have opacity enabled in the compositor, you can see the windows merging in the upper left corner.

Applied your fix as well.

[daltomi]

It looks good to me; I don't see anything else I'd change. Thank you.