What

When crafting gear/gildings you often want to maximize the stat bonuses from items whilst minimizing the quality of materials you need to use. It is however bothersome to calculate the required quality for specific stat bonuses all the time. So I made a spreadsheet which shows the minimum quality you need for an item to get a stat bonus X from an item which has quality 10 bonus Y.

Why

Say I want to craft a bear tooth talisman which has +3 strength bonus at quality 10. I have a string quality 100 and two bear teeth, one quality 110 and one quality 140. These would result in amulets of quality 105 or 120. The threshold for 8 strength is quality 100.28 and for 9 strength it's 122.50. This means both amulets would give the same 8 strength, so I might as well use the quality 110 tooth to not waste my higher quality one.

I don't know if anyone else actually bothers to do this optimization, but thought I'd share it.

How

The bonus formula is:

bonus = q10Bonus * sqrt(qItem / 10)

The bonus is rounded to the nearest integer, so the right hand side threshold is every value at x.5. This gives the required item quality formula:

qReq = 10 * ((bonus - 0.5) / q10Bonus)^2