png++  0.2.9
pixel_traits.hpp
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1 /*
2  * Copyright (C) 2007,2008 Alex Shulgin
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31 #ifndef PNGPP_PIXEL_TRAITS_HPP_INCLUDED
32 #define PNGPP_PIXEL_TRAITS_HPP_INCLUDED
33 
34 #include <limits>
35 #include "types.hpp"
36 
37 namespace png
38 {
39 
48  template< typename pixel > struct pixel_traits;
49 
56  template< typename pixel,
57  typename component,
58  color_type pixel_color_type,
59  int channels_value = sizeof(pixel) / sizeof(component),
60  int bit_depth_value = std::numeric_limits< component >::digits >
62  {
63  typedef pixel pixel_type;
64  typedef component component_type;
65 
67  {
68  return pixel_color_type;
69  }
70 
71  static const int channels = channels_value;
72  static int get_channels()
73  {
74  return channels;
75  }
76 
77  static const int bit_depth = bit_depth_value;
78  static int get_bit_depth()
79  {
80  return bit_depth;
81  }
82  };
83 
88  template< typename component >
90  {
95  static component get_alpha_filler()
96  {
97  return std::numeric_limits< component >::max();
98  }
99  };
100 
101 } // namespace png
102 
103 #endif // PNGPP_PIXEL_TRAITS_HPP_INCLUDED
static int get_channels()
Definition: pixel_traits.hpp:72
static const int bit_depth
Definition: pixel_traits.hpp:77
pixel pixel_type
Definition: pixel_traits.hpp:63
Pixel traits class template.
Definition: pixel_traits.hpp:48
color_type
Definition: types.hpp:46
static component get_alpha_filler()
Returns the default alpha channel filler for full opacity.
Definition: pixel_traits.hpp:95
static const int channels
Definition: pixel_traits.hpp:71
static int get_bit_depth()
Definition: pixel_traits.hpp:78
Basic pixel traits class template.
Definition: pixel_traits.hpp:61
static color_type get_color_type()
Definition: pixel_traits.hpp:66
Definition: color.hpp:36
component component_type
Definition: pixel_traits.hpp:64
Basic pixel traits class template for pixels with alpha channel.
Definition: pixel_traits.hpp:89