Random number

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There is no built-in entity to generate random numbers in Valve's Source games.

However, you can use logic_case's PickRandom input to trigger one of up to sixteen random outputs.

IUniformRandomStream

//----------------------------------------------------------------------------- // A generator of uniformly distributed random numbers //----------------------------------------------------------------------------- class IUniformRandomStream { public: // Sets the seed of the random number generator virtual void SetSeed( int iSeed ) = 0;

// Generates random numbers virtual float RandomFloat( float flMinVal = 0.0f, float flMaxVal = 1.0f ) = 0; virtual int RandomInt( int iMinVal, int iMaxVal ) = 0; virtual float RandomFloatExp( float flMinVal = 0.0f, float flMaxVal = 1.0f, float flExponent = 1.0f ) = 0; };

This is a random generator included in the source SDK, which allows you to generate random numbers, for instance to choose a random spawn point within an area:

CEmpSpawn *picked = candidates[random->RandomInt(0, candidates.Count() - 1)];

Note the - 1; Although it is not documented anywhere, RandomInt(0,1) includes the upperbound, unlike its counterpart in the C++ stdlib and boost libraries. This upper bound behaviour can be readily tested by putting this anywhere you know will run:

for (int i = 0; i < 50000; ++i) {

 Assert(random->RandomInt(0, 2) < 2);

}