Angelouscuitry opened this issue on Apr 05, 2007 · 30 posts
bagginsbill posted Fri, 29 February 2008 at 11:00 AM
Quote - Why is it that values of 2(for Value_1,) and 1(for Value_2) cause more of a dissplacement than values of 1, and .5
That's pretty simple. Let:
M mean the value of the displacement map image - we know that 0 <= M <= 1.
A mean a Math:Subtract with Value_1=1 and Value_2 = .5. So A(M) = M - .5
B mean a Math:Subtract with Value_1=2 and Value_2 = 1. So B(M) = 2M - 1
Now you asked why does B cause more displacement than A?
So - this is quite simple.
B(M) = 2M - 1 # by definition
B(M)/2 = M - .5
B(M)/2 = A(M)
B(M) = 2 A(M)
So - we conclude that B(M) is always twice A(M).
As a little check, we examine the boundary cases where M = 0 and M = 1.
B(0) = -1, B(1) = 1
A(0) = -.5, A(1) = .5
Looks right.
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