Developer Documentation

RandomNumberGenerator.cc
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41
42 //=============================================================================
43 //
44 // Helper Functions for generating a random number between 0.0 and 1.0 with
45 // a garantueed resolution
46 //
47 //=============================================================================
48
49
50 //== INCLUDES =================================================================
51
52
53 #include <OpenMesh/Core/Utils/RandomNumberGenerator.hh>
54
55
56 //== NAMESPACES ===============================================================
57
58
59 namespace OpenMesh {
60
61
62 //== IMPLEMENTATION ===========================================================
63
64 RandomNumberGenerator::RandomNumberGenerator(const size_t _resolution) :
65 resolution_(_resolution),
66 iterations_(1),
67 maxNum_(RAND_MAX + 1.0)
68 {
69 double tmp = double(resolution_);
70 while (tmp > (double(RAND_MAX) + 1.0) ) {
71 iterations_++;
72 tmp /= (double(RAND_MAX) + 1.0);
73 }
74
75 for ( unsigned int i = 0 ; i < iterations_ - 1; ++i ) {
76 maxNum_ *= (RAND_MAX + 1.0);
77 }
78 }
79
80 //-----------------------------------------------------------------------------
81
82 double RandomNumberGenerator::getRand() const {
83 double randNum = 0.0;
84 for ( unsigned int i = 0 ; i < iterations_; ++i ) {
85 randNum *= (RAND_MAX + 1.0);
86 randNum += rand();
87 }
88
89 return randNum / maxNum_;
90 }
91
92 double RandomNumberGenerator::resolution() const {
93 return maxNum_;
94 }
95
96 //=============================================================================
97 } // namespace OpenMesh
98 //=============================================================================
OpenMesh::RandomNumberGenerator::maxNum_
double maxNum_
maximum random number generated, which is used for normalization
Definition: RandomNumberGenerator.hh:101
OpenMesh::RandomNumberGenerator::RandomNumberGenerator
RandomNumberGenerator(const size_t _resolution)
Constructor.
Definition: RandomNumberGenerator.cc:64
OpenMesh::RandomNumberGenerator::resolution_
const size_t resolution_
desired resolution
Definition: RandomNumberGenerator.hh:95
OpenMesh::RandomNumberGenerator::iterations_
size_t iterations_
number of "blocks" of RAND_MAX that make up the desired _resolution
Definition: RandomNumberGenerator.hh:98
OpenMesh
Definition: MeshItems.hh:59
OpenMesh::RandomNumberGenerator::getRand
double getRand() const
returns a random double between 0.0 and 1.0 with a guaranteed resolution
Definition: RandomNumberGenerator.cc:82