Re: [PATCH] uxtheme: Support images in GetThemeBackgroundRegion. (try 2)

[Alexandre Julliard]

Mark Harmstone <hellas(a)burntcomma.com> writes:
> +    /* loop through the image looking for transparent pixels,
> +     * grouping together horizontal runs into one rect */
> +    ptr = bits;
> +    for (y = 0; y < r.bottom; y++) {
> +        BOOL trans = FALSE;
> +        int transstart;
> +
> +        for (x = 0; x < r.right; x++) {
> +            COLORREF colour = ptr[2] << 16 | ptr[1] << 8 | ptr[0];
> +            ptr += 4;
> +
> +            if (colour == transcolour) {
> +                if (!trans) {
> +                    transstart = x;
> +                    trans = TRUE;
> +                }
> +            } else if (trans) {
> +                rgntemp = CreateRectRgn(transstart, y, x, y+1);
> +                CombineRgn(hrgn, hrgn, rgntemp, RGN_DIFF);
> +                DeleteObject(rgntemp);
> +                trans = FALSE;
> +            }
> +        }
> +
> +        if (trans) {
> +            rgntemp = CreateRectRgn(transstart, y, r.right, y+1);
> +            CombineRgn(hrgn, hrgn, rgntemp, RGN_DIFF);
> +            DeleteObject(rgntemp);
> +        }
> +    }

That's going to be pretty slow. There's a better implementation in
winex11.drv:update_surface_region(), you could just copy that.

-- 
Alexandre Julliard
julliard(a)winehq.org