Developer Documentation

GLFormatInfo.hh
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40 \*===========================================================================*/
41
42
43 //=============================================================================
44 //
45 // OpenGL texture format info
46 //
47 //=============================================================================
48
49
50 #ifndef GL_FORMATINFO_HH
51 #define GL_FORMATINFO_HH
52
53
54 //== INCLUDES =================================================================
55
56 // GL
57 #include <ACG/GL/acg_glew.hh>
58 #include <ACG/GL/gl.hh>
59
60 // C++
61 #include <map>
62
63
64 //== NAMESPACES ===============================================================
65
66 namespace ACG {
67
68 //== CLASS DEFINITION =========================================================
69
70 class ACGDLLEXPORT GLFormatInfo
71 {
72 public:
73 explicit GLFormatInfo(GLenum _internalFormat);
74
75 GLFormatInfo();
76 ~GLFormatInfo();
77
78 // size in bytes of the i'th channel
79 int channelSize(int i = 0) const {assert(i >= 0 && i < channelCount_); return channelBits_[i] >> 3;}
80
81 // size in bits of the i'th channel
82 int channelBits(int i) const {assert(i >= 0 && i < channelCount_); return channelBits_[i];}
83
84 // number of channels
85 int channelCount() const {return channelCount_;}
86
87 // size in bytes of one element = num channels * channel size
88 int elemSize() const {return bpp_ >> 3;}
89
90 // bits per pixel
91 int bpp() const {return bpp_;}
92
93 // get internal format
94 GLenum internalFormat() const {return internalFormat_;}
95
96 // get a fitting (external) format for the internalfmt, ie. GL_RED, GL_RGBA, GL_RGBA_INTEGER etc.
97 GLenum format() const {return format_;}
98
99 // get a fitting data-type for the internalfmt, ie GL_UNSIGNED_BYTE, GL_FLOAT etc.
100 GLenum type() const {return type_;}
101
102 // some formats such as GL_RGBA, GL_R8 etc. are normalized to [0,1] when sampled
103 bool isNormalized() const {return normalized_;}
104
105 // data can be one of 3 unsized base types: floating pt, signed integer or unsigned integer
106 enum BaseType
107 {
108 FloatingPt,
109 SignedInt,
110 UnsignedInt
111 };
112
113 bool isFloat() const {return baseType_ == FloatingPt;}
114 bool isUint() const {return baseType_ == UnsignedInt;}
115 bool isInt() const {return baseType_ == SignedInt;}
116
117 bool isValid() const {return bpp_ != 0;}
118
119 BaseType baseType() const {return baseType_;}
120
121 // return string of the sized internalFormat, ie. GL_RGBA8, GL_RG32F etc.
122 const char* sizedFormatString() const {return sizedName_;}
123
124 private:
125 GLFormatInfo( GLenum _intfmt, GLenum _fmt, GLenum _type, int _r, int _g, int _b, int _a, BaseType _bt, bool _nrm);
126 static void registerFmt(GLenum _intfmt, GLenum _fmt, GLenum _type, int _r, int _g, int _b, int _a, BaseType _bt, bool _nrm);
127
128 GLenum internalFormat_,
129 format_,
130 type_;
131
132 int channelBits_[4];
133
134 int channelCount_,
135 bpp_;
136
137 // 0 -> floating point, 1 -> unsigned integer, 2 -> signed integer
138 BaseType baseType_;
139
140 bool normalized_;
141
142 char sizedName_[32];
143
144 // map from internalfmt to info
145 static std::map<GLenum, GLFormatInfo> formatMap_;
146 };
147
148
149 //=============================================================================
150 } // namespace ACG
151 //=============================================================================
152 #endif // GL_FORMATINFO_HH defined
153 //=============================================================================
ACG::GLFormatInfo
Definition: GLFormatInfo.hh:70
ACG
Namespace providing different geometric functions concerning angles.
Definition: BaseObjectData.hh:68