Geometry..

The entries for the London Hat Week exhibition need to be in by the first week of November. The theme is 'To the future and back' and you can make either a futuristic or vintage inspired hat. I am going with the vintage theme, and have some 'French net curtain' that I want to use to make a large dior brimmed hat. The curtain is in panels, so I am calculating how many panels I need to make the size of hat I want using  basic trigonometry.