Comment 8 for bug 212768

The latter problem (changing the dimensions of the visual bounding box of selection of multiple objects having different stroke widths) should have been solved as of rev. #10442

@LucaDC: the formula was indeed wrong. It's a simple problem, but still the result is very complex for some reason. I needed to change a simple ABC formula into this:

r1h=(r0h*sqrt(r0h^2*w1^2+((4*h0*h1-4*h1*r0h)*w0+(2*h1*r0h-4*h0*h1)*r0w)*w1+h1^2*r0w^2)+r0h^2*w1+h1*r0h*r0w)/((2*r0h-2*h0)*w0+2*h0*r0w)

r1w=(w0*(r0w*
(h0*h1*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)-h1*r0h*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2))
+(h0*h1^2-h1^2*r0h)*r0w^2)+w1*
(r0h^2*r0w*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)+(3*h0*h1*r0h-3*h1*r0h^2)*r0w*w0+(2*h1*r0h^2-3*h0*h1*r0h)*r0w^2)+r0w^2*
(h1*r0h*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)-h0*h1*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2))
+r0h^3*r0w*w1^2+(h1^2*r0h-h0*h1^2)*r0w^3)/(w0*(r0h^2*sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)-h0*r0h*
sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)+(h1*r0h^2-5*h0*h1*r0h+4*h0^2*h1)*r0w)+h0*r0h*r0w*
sqrt(r0h^2*w1^2-4*h1*r0h*w0*w1+4*h0*h1*w0*w1+2*h1*r0h*r0w*w1-4*h0*h1*r0w*w1+h1^2*r0w^2)+((r0h^3-h0*r0h^2)*w0+h0*r0h^2*r0w)*w1+(-2*h1*r0h^2+4*h0*h1*r0h-2*h0^2*h1)*w0^2+
(h0*h1*r0h-2*h0^2*h1)*r0w^2)

See http://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/revision/10442 for more details; It can be simplified somewhat, but still...