Add a check for src == dst in ocl warpTransform #25898
As mentioned in #25853, when doing WarpAffine with Mat and UMat respectively, if you force the use of the in-place operation (so that src and dst are passed the same variables), Mat produces the correct results, but UMat produces unexpected results.
Obviously in-place operations are not possible with this transformation. When Mat performs the operation, if dst and src are the same variable, the function inherently makes a copy of src without telling the user.
74b50c7af0/modules/imgproc/src/imgwarp.cpp (L2831-L2834)
So I did the same check in UMat, but I'm not sure if it's appropriate, should we just do a copy operation without telling the user (even if the user thinks he's doing an in-place operation), or should we throw an exception to indicate that we shouldn't pass in two same variables here?
The possible reason for this problem is that there is a create function here, so it gives the developer the false impression that this create function has allocated new memory for dst, however it does not.
74b50c7af0/modules/imgproc/src/imgwarp.cpp (L2607-L2609)
Because by the time the check is done here, the function has returned back.
74b50c7af0/modules/core/src/umatrix.cpp (L668-L675)
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