I would expect (based on intuition, and the implementation of AffineTransform
in Java):
a.postConca开发者_StackOverflow中文版t(b) -> a = a x b
a.preConcat(b) -> a = b x a
but according to the android documentation:
public boolean preConcat (Matrix other)
Preconcats the matrix with the specified matrix. M' = M x other
public boolean postConcat (Matrix other)
Postconcats the matrix with the specified matrix. M' = other x M
This seems backwards to me, am I missing something?
I suppose that the method 'post concat' is called so because the transformation, which the matrix other
describes, is performed after the transformation matrix M
stands for.
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