Developer Documentation
TextureMath.cc
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49 
50 #include "TextureMath.hh"
51 
52 #include <cmath>
53 
54 TextureMath::TextureMath(const bool _abs,
55  const bool _clamp,
56  const double _clampMin,
57  const double _clampMax,
58  const bool _repeat,
59  const double _minRepeat,
60  const double _maxRepeat,
61  const bool _center,
62  const bool _scale,
63  const double _minimalInput,
64  const double _maximalInput):
65  abs_(_abs),
66  clamp_(_clamp),
67  clampMin_(_clampMin),
68  clampMax_(_clampMax),
69  repeat_(_repeat),
70  repeatMin_(_minRepeat),
71  repeatMax_(_maxRepeat),
72  center_(_center),
73  scale_(_scale),
74  minInput_(_minimalInput),
75  maxInput_(_maximalInput)
76 {
77 
78 }
79 
80 TextureMath::TextureMath(const TexParameters& _parameters, const double _minimalInput, const double _maximalInput) :
81  abs_(_parameters.abs),
82  clamp_(_parameters.clamp),
83  clampMin_(_parameters.clampMin),
84  clampMax_(_parameters.clampMax),
85  repeat_(_parameters.repeat),
86  repeatMin_(_parameters.repeatMin),
87  repeatMax_(_parameters.repeatMax),
88  center_(_parameters.center),
89  scale_(_parameters.scale),
90  minInput_(_minimalInput),
91  maxInput_(_maximalInput)
92 {
93 }
94 
95 double TextureMath::transform(const double _input) const
96 {
97  double value = _input;
98 
99 
100  // Use absolute value as requested by plugin
101  if ( abs_ )
102  value = fabs(value);
103 
104  // Clamp if requested
105  if ( clamp_ ) {
106  if ( value > clampMax_ )
107  value = clampMax_;
108  if (value < clampMin_)
109  value = clampMin_;
110  }
111 
112  // if all texCoords have the same value
113  if ( minInput_ == maxInput_){
114 
115  if ( ! repeat_ )
116  value = 0.0;
117  else
118  value = maxInput_;
119 
120  return value;
121  }
122 
123 
124  // if the texture should not be repeated, scale to 0..1
125  if ( ! repeat_ ) {
126  if (! center_ ) {
127  if ( scale_) {
128  value /= fabs(maxInput_) + fabs(minInput_); //scaleFactor is != 0.0 (otherwise _min==_max)
129  value -= minInput_/(fabs(maxInput_) + fabs(minInput_));
130  }
131  } else {
132  // the values above zero are mapped to 0.5..1 the negative ones to 0.5..0
133  if (value > 0.0) {
134  value /= ( maxInput_ * 2.0); //_max >= _value > 0.0
135  value += 0.5;
136  } else {
137  if ( minInput_ == 0.0 ){
138  value = 0.0;
139  } else {
140  value /= ( minInput_ * 2.0);
141  value = 0.5 - value;
142  }
143  }
144  }
145  } else {
146  value -= minInput_;
147  value *= (repeatMax_ - repeatMin_) / (maxInput_ - minInput_);
148  value += repeatMin_;
149  }
150 
151  return value;
152 }
TextureMath(const bool _abs, const bool _clamp, const double _clampMin, const double _clampMax, const bool _repeat, const double _minRepeat, const double _maxRepeat, const bool _center, const bool _scale, const double _minimalInput, const double _maximalInput)
Definition: TextureMath.cc:54
double transform(const double _input) const
Modify given values based on the specified parameters given to the constructor.
Definition: TextureMath.cc:95