Developer Documentation
GLFormatInfo.hh
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51 
52 //=============================================================================
53 //
54 // OpenGL texture format info
55 //
56 //=============================================================================
57 
58 
59 #ifndef GL_FORMATINFO_HH
60 #define GL_FORMATINFO_HH
61 
62 
63 //== INCLUDES =================================================================
64 
65 // GL
66 #include <ACG/GL/gl.hh>
67 
68 // C++
69 #include <map>
70 
71 
72 //== NAMESPACES ===============================================================
73 
74 namespace ACG {
75 
76 //== CLASS DEFINITION =========================================================
77 
78 class ACGDLLEXPORT GLFormatInfo
79 {
80 public:
81  GLFormatInfo(GLenum _internalFormat);
82 
83  GLFormatInfo();
84  ~GLFormatInfo();
85 
86  // size in bytes of the i'th channel
87  int channelSize(int i = 0) const {assert(i >= 0 && i < channelCount_); return channelBits_[i] >> 3;}
88 
89  // size in bits of the i'th channel
90  int channelBits(int i) const {assert(i >= 0 && i < channelCount_); return channelBits_[i];}
91 
92  // number of channels
93  int channelCount() const {return channelCount_;}
94 
95  // size in bytes of one element = num channels * channel size
96  int elemSize() const {return bpp_ >> 3;}
97 
98  // bits per pixel
99  int bpp() const {return bpp_;}
100 
101  // get internal format
102  GLenum internalFormat() const {return internalFormat_;}
103 
104  // get a fitting (external) format for the internalfmt, ie. GL_RED, GL_RGBA, GL_RGBA_INTEGER etc.
105  GLenum format() const {return format_;}
106 
107  // get a fitting data-type for the internalfmt, ie GL_UNSIGNED_BYTE, GL_FLOAT etc.
108  GLenum type() const {return type_;}
109 
110  // some formats such as GL_RGBA, GL_R8 etc. are normalized to [0,1] when sampled
111  bool isNormalized() const {return normalized_;}
112 
113  // data can be one of 3 unsized base types: floating pt, signed integer or unsigned integer
114  enum BaseType
115  {
116  FloatingPt,
117  SignedInt,
118  UnsignedInt
119  };
120 
121  bool isFloat() const {return baseType_ == FloatingPt;}
122  bool isUint() const {return baseType_ == UnsignedInt;}
123  bool isInt() const {return baseType_ == SignedInt;}
124 
125  bool isValid() const {return bpp_ != 0;}
126 
127  BaseType baseType() const {return baseType_;}
128 
129  // return string of the sized internalFormat, ie. GL_RGBA8, GL_RG32F etc.
130  const char* sizedFormatString() const {return sizedName_;}
131 
132 private:
133  GLFormatInfo( GLenum _intfmt, GLenum _fmt, GLenum _type, int _r, int _g, int _b, int _a, BaseType _bt, bool _nrm);
134  static void registerFmt(GLenum _intfmt, GLenum _fmt, GLenum _type, int _r, int _g, int _b, int _a, BaseType _bt, bool _nrm);
135 
136  GLenum internalFormat_,
137  format_,
138  type_;
139 
140  int channelBits_[4];
141 
142  int channelCount_,
143  bpp_;
144 
145  // 0 -> floating point, 1 -> unsigned integer, 2 -> signed integer
146  BaseType baseType_;
147 
148  bool normalized_;
149 
150  char sizedName_[32];
151 
152  // map from internalfmt to info
153  static std::map<GLenum, GLFormatInfo> formatMap_;
154 };
155 
156 
157 //=============================================================================
158 } // namespace ACG
159 //=============================================================================
160 #endif // GL_FORMATINFO_HH defined
161 //=============================================================================
ACG
Namespace providing different geometric functions concerning angles.
Definition: DBSCANT.cc:51