D14784: [scenes/opengl] Fix overlaps in shadow texture atlas

davidedmundson added inline comments.

INLINE COMMENTS

> scene_opengl.cpp:2425-2426
> +
>      p.drawPixmap(0, 0, shadowPixmap(ShadowElementTopLeft));
> -    p.drawPixmap(topLeft.width(), 0, shadowPixmap(ShadowElementTop));
> -    p.drawPixmap(topLeft.width() + top.width(), 0, shadowPixmap(ShadowElementTopRight));
> -    p.drawPixmap(0, topLeft.height(), shadowPixmap(ShadowElementLeft));
> -    p.drawPixmap(width - right.width(), topRight.height(), shadowPixmap(ShadowElementRight));
> -    p.drawPixmap(0, topLeft.height() + left.height(), shadowPixmap(ShadowElementBottomLeft));
> -    p.drawPixmap(bottomLeft.width(), height - bottom.height(), shadowPixmap(ShadowElementBottom));
> -    p.drawPixmap(bottomLeft.width() + bottom.width(), topRight.height() + right.height(), shadowPixmap(ShadowElementBottomRight));
> +    p.drawPixmap(innerRectLeft, 0, shadowPixmap(ShadowElementTop));
> +    p.drawPixmap(width - topRight.width(), 0, shadowPixmap(ShadowElementTopRight));

If left is wider than topleft then we'll end up with a gap between the topleft and top.

Personally I'd call that a corrupt data and not care, which is what the code currently does.
But this whole patch is about handling corrupt shadows.

---

We could either p.drawPixmap(QRect, QImage)  so it scales to fill the quadrant

or

p.drawPixmap( innerRectLeft - shadowElementTopLeft.width(), ....)

so that we align the topLeft element to the right of it's allocated rectangle.

(or the equivalent with style()->drawItemPixmap)

REPOSITORY
  R108 KWin

REVISION DETAIL
  https://phabricator.kde.org/D14784

To: zzag, #kwin
Cc: davidedmundson, abetts, kwin, mkulinski, ragreen, jackyalcine, Pitel, iodelay, bwowk, ZrenBot, lesliezhai, ali-mohamed, hardening, jensreuterberg, sebas, apol, mart