Developer Documentation
HuePartitioningColors.cc
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49 
50 #include "HuePartitioningColors.hh"
51 
52 #include <QColor>
53 
54 namespace ACG {
55 
56 #define DEFAULT_SATURATION 1.0f
57 #define DEFAULT_VALUE 1.0f
58 
59 HuePartitioningColors::HuePartitioningColors(float _alpha, float _baseHue) :
60  currentSubdiv_(2), currentIt_(0), currentTriadIt_(0),
61  alpha_(_alpha), baseHue_(_baseHue),
62  defaultSaturation_(DEFAULT_SATURATION), defaultValue_(DEFAULT_VALUE) {
63 }
64 
65 static inline float wrap01(float v) {
66  float dummy;
67  if (v > 1.0f) v = modff(v, &dummy);
68  if (v < 0.0f) v = 1.0f - modff(v, &dummy);
69  return v;
70 }
71 
73  const float resultHue =
74  baseHue_
75  + .33333333f / currentSubdiv_ * currentIt_
76  + .33333333f * currentTriadIt_;
77 
78  // Convert color to RGB and store result.
79  double r, g, b, a;
80  QColor::fromHsvF(wrap01(resultHue), defaultSaturation_,
81  defaultValue_, alpha_).getRgbF(
82  &r, &g, &b, &a);
83  const Vec4f result(r, g, b, alpha_);
84 
85  /*
86  * Increment the three level iterator state.
87  */
88 
89  // Level 1: Increment triad it.
90  if (++currentTriadIt_ <= 2)
91  return result;
92 
93  // Level 2: Increment subdiv it.
94  currentTriadIt_ = 0;
95 
96  // Starting from the second subdivison, only visit odd numbers.
97  currentIt_ += (currentSubdiv_ == 2 ? 1 : 2);
98  if (currentIt_ < currentSubdiv_)
99  return result;
100 
101  // Level 3: Increment subdivision level.
102  currentIt_ = 1;
103  currentSubdiv_ *= 2;
104 
105  return result;
106 }
107 
108 } /* namespace ACG */
HuePartitioningColors(float _alpha=1.0f, float _baseHue=0.5694f)
Namespace providing different geometric functions concerning angles.
Definition: DBSCANT.cc:51