Fixes bug where certain input values for top/left parameters
in composite can conflict with clipping logic, resulting in
inaccurate alignment in output.
A top or left offset value of -1 will no longer mean that the
value is not set, but will now be an actual offset of -1.
INT_MIN for left & top will mean that the values are not set.
Co-authored-by: Christian Flintrup <chr@gigahost.dk>