D1uIsNull : ||D1U|| <= Resolution
D1vIsNull : ||D1V|| <= Resolution
D1IsNull : the first derivatives in the U and V parametric
directions have null length :
||D1U|| <= Resolution and ||D1V|| <= Resolution
D1uD1vRatioIsNull : the first derivative in the U direction has
null length by comparison with the derivative
in the V direction
||D1U|| / ||D1V|| <= RealEpsilon
D1vD1uRatioIsNull : the first derivative in the V direction has
null length by comparison with the derivative
in the U direction
||D1V|| / ||D1U|| <= RealEpsilon
D1uIsParallelD1v : the angle between the derivatives in the U and
V direction is null (tolerance criterion given
as input data)
More...
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1.6.3