Inconsistent handling of default seed in NormalGenerator & UniformGenerator

[SunBlack]

As already discussed here default seed in random.h is not handled consistently.

pcl/common/include/pcl/common/random.h

Lines 163 to 186 in b4c785b

	struct Parameters
	{
	Parameters (T _mean = 0, T _sigma = 1, pcl::uint32_t _seed = 1)
	: mean (_mean)
	, sigma (_sigma)
	, seed (_seed)
	{}
	T mean;
	T sigma;
	pcl::uint32_t seed;
	};
	/** Constructor
	* \param[in] mean normal mean
	* \param[in] sigma normal variation
	* \param[in] seed seeding value
	*/
	NormalGenerator(T mean = 0, T sigma = 1, pcl::uint32_t seed = -1);
	/** Constructor
	* \param parameters normal distribution parameters and seed
	*/
	NormalGenerator(const Parameters& parameters);

One constructor of NormalGenerator has as default seed -1 during the other one (via Parameters) has 1 as default seed.

Furthermore you get currently following warning:

common/include/pcl/common/impl/random.hpp:49:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
   if(parameters_.seed != -1)

So we should discuss how to adjust code there.

[SunBlack]

My suggestion: Remove/Deprecate struct Parameters and add new methods:

Instead of setParameters (T min, T max, pcl::uint32_t seed = -1); we should have setParameters (T min, T max); and setParameters (T min, T max, pcl::uint32_t seed); So instead of a default value we use two different methods. First use existing random generator, during second implementation is using first implementation, but set a new seed on random generator.

[stale]

Marking this as stale due to 30 days of inactivity. It will be closed in 7 days if no further activity occurs.

[kunaltyagi]

TODO list:

• move Parameters to private with name ParameterImpl
• add an alias and deprecate it
• deprecate the setParameters function using Parameters
• add a function without default seed and remove the default value for seed in current impl

This will still break API in that way, but with deprecation.

Any counter opinions (or any other opinions 😄)?