1GLPIXELMAP(3G) GLPIXELMAP(3G)
2
6 glPixelMapfv, glPixelMapuiv, glPixelMapusv - set up pixel transfer maps
7
10 void glPixelMapfv( GLenum map,
11 GLint mapsize,
12 const GLfloat *values )
13 void glPixelMapuiv( GLenum map,
14 GLint mapsize,
15 const GLuint *values )
16 void glPixelMapusv( GLenum map,
17 GLint mapsize,
18 const GLushort *values )
19
22 map Specifies a symbolic map name. Must be one of the following:
23 GL_PIXEL_MAP_I_TO_I, GL_PIXEL_MAP_S_TO_S, GL_PIXEL_MAP_I_TO_R,
24 GL_PIXEL_MAP_I_TO_G, GL_PIXEL_MAP_I_TO_B, GL_PIXEL_MAP_I_TO_A,
25 GL_PIXEL_MAP_R_TO_R, GL_PIXEL_MAP_G_TO_G, GL_PIXEL_MAP_B_TO_B,
26 or GL_PIXEL_MAP_A_TO_A.
27 mapsize Specifies the size of the map being defined.
29 values Specifies an array of mapsize values.
31
33 glPixelMap sets up translation tables, or maps, used by glCopyPixels,
34 glCopyTexImage1D, glCopyTexImage2D, glCopyTexSubImage1D,
35 glCopyTexSubImage2D, glCopyTexSubImage3D, glDrawPixels, glReadPixels,
36 glTexImage1D, glTexImage2D, glTexImage3D, glTexSubImage1D,
37 glTexSubImage2D, and glTexSubImage3D. Additionally, if the
38 GL_ARB_imaging subset is supported, the routines glColorTable,
39 glColorSubTable, glConvolutionFilter1D, glConvolutionFilter2D,
40 glHistogram, glMinmax, and glSeparableFilter2D. Use of these maps is
41 described completely in the glPixelTransfer reference page, and partly
42 in the reference pages for the pixel and texture image commands. Only
43 the specification of the maps is described in this reference page.
44 map is a symbolic map name, indicating one of ten maps to set. mapsize
46 specifies the number of entries in the map, and values is a pointer to
47 an array of mapsize map values.
48 The ten maps are as follows:
50 GL_PIXEL_MAP_I_TO_I Maps color indices to color indices.
52 GL_PIXEL_MAP_S_TO_S Maps stencil indices to stencil indices.
54 GL_PIXEL_MAP_I_TO_R Maps color indices to red components.
56 GL_PIXEL_MAP_I_TO_G Maps color indices to green components.
58 GL_PIXEL_MAP_I_TO_B Maps color indices to blue components.
60 GL_PIXEL_MAP_I_TO_A Maps color indices to alpha components.
62 GL_PIXEL_MAP_R_TO_R Maps red components to red components.
64 GL_PIXEL_MAP_G_TO_G Maps green components to green compo‐
66 nents.
67 GL_PIXEL_MAP_B_TO_B Maps blue components to blue components.
69 GL_PIXEL_MAP_A_TO_A Maps alpha components to alpha compo‐
71 nents.
72 The entries in a map can be specified as single-precision floating-
74 point numbers, unsigned short integers, or unsigned long integers.
75 Maps that store color component values (all but GL_PIXEL_MAP_I_TO_I and
76 GL_PIXEL_MAP_S_TO_S) retain their values in floating-point , with
77 unspecified mantissa and exponent sizes. Floating-point values speci‐
78 fied by glPixelMapfv are converted directly to the internal floating-
79 point of these maps, then clamped to the range [0,1]. Unsigned inte‐
80 ger values specified by glPixelMapusv and glPixelMapuiv are converted
81 linearly such that the largest representable integer maps to 1.0, and 0
82 maps to 0.0.
83 Maps that store indices, GL_PIXEL_MAP_I_TO_I and GL_PIXEL_MAP_S_TO_S,
85 retain their values in fixed-point , with an unspecified number of bits
86 to the right of the binary point. Floating-point values specified by
87 glPixelMapfv are converted directly to the internal fixed-point of
88 these maps. Unsigned integer values specified by glPixelMapusv and
89 glPixelMapuiv specify integer values, with all 0's to the right of the
90 binary point.
91 The following table shows the initial sizes and values for each of the
93 maps. Maps that are indexed by either color or stencil indices must
94 have mapsize = 2n for some n or the results are undefined. The maximum
95 allowable size for each map depends on the implementation and can be
96 determined by calling glGet with argument GL_MAX_PIXEL_MAP_TABLE. The
97 single maximum applies to all maps; it is at least 32.
98 ─────────────────────────────────────────────────────────────────────────────────────
100 map Lookup Index Lookup Value Initial Size Initial Value
101 ─────────────────────────────────────────────────────────────────────────────────────
102 GL_PIXEL_MAP_I_TO_I color index color index 1 0
103 GL_PIXEL_MAP_S_TO_S stencil index stencil index 1 0
104 GL_PIXEL_MAP_I_TO_R color index R 1 0
105 GL_PIXEL_MAP_I_TO_G color index G 1 0
106 GL_PIXEL_MAP_I_TO_B color index B 1 0
107 GL_PIXEL_MAP_I_TO_A color index A 1 0
108 GL_PIXEL_MAP_R_TO_R R R 1 0
109 GL_PIXEL_MAP_G_TO_G G G 1 0
110 GL_PIXEL_MAP_B_TO_B B B 1 0
111 GL_PIXEL_MAP_A_TO_A A A 1 0
112 ─────────────────────────────────────────────────────────────────────────────────────
113
116 GL_INVALID_ENUM is generated if map is not an accepted value.
117 GL_INVALID_VALUE is generated if mapsize is less than one or larger
119 than GL_MAX_PIXEL_MAP_TABLE.
120 GL_INVALID_VALUE is generated if map is GL_PIXEL_MAP_I_TO_I,
122 GL_PIXEL_MAP_S_TO_S, GL_PIXEL_MAP_I_TO_R, GL_PIXEL_MAP_I_TO_G,
123 GL_PIXEL_MAP_I_TO_B, or GL_PIXEL_MAP_I_TO_A, and mapsize is not a power
124 of two.
125 GL_INVALID_OPERATION is generated if glPixelMap is executed between the
127 execution of glBegin and the corresponding execution of glEnd.
128
130 glGetPixelMap
131 glGet with argument GL_PIXEL_MAP_I_TO_I_SIZE
132 glGet with argument GL_PIXEL_MAP_S_TO_S_SIZE
133 glGet with argument GL_PIXEL_MAP_I_TO_R_SIZE
134 glGet with argument GL_PIXEL_MAP_I_TO_G_SIZE
135 glGet with argument GL_PIXEL_MAP_I_TO_B_SIZE
136 glGet with argument GL_PIXEL_MAP_I_TO_A_SIZE
137 glGet with argument GL_PIXEL_MAP_R_TO_R_SIZE
138 glGet with argument GL_PIXEL_MAP_G_TO_G_SIZE
139 glGet with argument GL_PIXEL_MAP_B_TO_B_SIZE
140 glGet with argument GL_PIXEL_MAP_A_TO_A_SIZE
141 glGet with argument GL_MAX_PIXEL_MAP_TABLE
142
144 glColorTable(3G), glColorSubTable(3G), glConvolutionFilter1D(3G),
145 glConvolutionFilter2D(3G), glCopyPixels(3G), glCopyTexImage1D(3G),
146 glCopyTexImage2D(3G), glCopyTexSubImage1D(3G), glCopyTexSubImage2D(3G),
147 glDrawPixels(3G), glHistogram(3G), glMinmax(3G), glPixelStore(3G),
148 glPixelTransfer(3G), glReadPixels(3G), glSeparableFilter2D(3G),
149 glTexImage1D(3G), glTexImage2D(3G), glTexImage3D(3G),
150 glTexSubImage1D(3G), glTexSubImage2D(3G), glTexSubImage3D(3G)
151 GLPIXELMAP(3G)