I have developed a chart and the equation and also have input these to excel spreadsheet. This will allow you to calculate any wall angle 0 to 90 deg with any number of sides 3 sides and up. The program will also give all the information you need for any pryamid shaped project. All this can be cut on any table saw or even a skil saw. All of the joints fit tight reguardless of the number of sides or the wall angle. If you are interested email me at firstname.lastname@example.org for further information.