swift3 - How do I create a circle packing algorithm for circles with unequal sizes in iOS? -

i trying pack bunch of round uiviews in hexagonal pattern. have different sizes.

first randomly generate uiviews , put them on screen shown:
have algorithm arranges views in circular pattern around center. algorithm:

func arrangeviews()     {         let viewcenter = self.view.center         let radius: double = 50?? <- put here? views has different radius?         var currentdistfromcenter: double = (radius * 2)         var nummoved = 0         let amountofviews = views.count          nummoved += 1          while nummoved < amountofviews {             var numbertofit = double(m_pi / asin(radius / currentdistfromcenter))              if numbertofit > double(amountofviews - nummoved) {                 numbertofit = double(amountofviews - nummoved)             }              in 0 ..< int(numbertofit) {                 let currentview = views[nummoved]                 let angle = double(m_pi * 2.0 * double(i) / numbertofit)                 let x = double(viewcenter.x) + cos(angle) * currentdistfromcenter                 let y = double(viewcenter.y) + sin(angle) * currentdistfromcenter                 var newpoint = cgpoint(x: cgfloat(x), y: cgfloat(y))                  views.first?.center = self.view.center                  if newpoint.x != currentview.frame.origin.x || newpoint.y != currentview.frame.origin.y {                     uiview.animate(withduration: 0.3, animations: {                         currentview.center = newpoint                     })                     nummoved += 1                 }             }             currentdistfromcenter += radius * 2         }     } 

here result after run function:

algorithm circles (views) same size. see don't lie next each other if had same size. shown here:

is there out there has form of clue change in algorithm can pack views different sizes?

here links i've encountered during research, haven't gotten me far because maths isn't strongest side:
http://www.optimization-online.org/db_file/2008/06/1999.pdf
packing different sized circles rectangle - d3.js
http://jsfiddle.net/tdzve/

thank in advance , happy programming!

as per result needed, prefer firstly draw 7 circles @ same center.

suppose red colored center circle of size (x, y, w, h)

then

1st (top left)         - (x-w/2, y-(h+h/2), w, h) 2nd (top right)        - (x+w/2, y-(h+h/2), w, h) 3rd (right)            - (x+w, y, w, h) 4th (bottom right)     - (x+w/2, y+(h+h/2), w, h) 5th (bottom left)      - (x-w/2, y+(h+h/2), w, h) 6th (left)             - (x-w, y, w, h) 

this applied in cases of hexagonal part, w/h change each circle like

1st (top left)         - (x-w/2, y-(h+h/2), w1, h1) 2nd (top right)        - (x+w/2, y-(h+h/2), w2, h2) 3rd (right)            - (x+w, y, w3, h3) 4th (bottom right)     - (x+w/2, y+(h+h/2), w4, h4) 5th (bottom left)      - (x-w/2, y+(h+h/2), w5, h5) 6th (left)             - (x-w, y, w6, h6)