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Advanced coordinate rotation: possible typo? #4
Description
Hi Billy, great book.
On page 228, there's a couple of equations
x1 = (x-centerX) * cos(rotation) - (y-centerY) * sin(rotation)
y1 = (y-centerY) * cos(rotation) + (x-centerX) * sin(rotation)
I tried coding these up and it certainly rotates the point, but it is offset by (-centerX, -centerY)
Should the equations be these?
x1 = centerX + [(x-centerX) * cos(rotation) - (y-centerY) * sin(rotation)]
y1 = centerY + [(y-centerY) * cos(rotation) + (x-centerX) * sin(rotation)]
Cheers,
Ed