1GLGETMINMAX(3G) GLGETMINMAX(3G)
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6 glGetMinmax - get minimum and maximum pixel values
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10 void glGetMinmax( GLenum target,
11 GLboolean reset,
12 GLenum format,
13 GLenum types,
14 GLvoid *values )
15
18 target Must be GL_MINMAX.
19 reset If GL_TRUE, all entries in the minmax table that are actually
21 returned are reset to their initial values. (Other entries are
22 unaltered.) If GL_FALSE, the minmax table is unaltered.
23 format The of the data to be returned in values. Must be one of
25 GL_RED, GL_GREEN, GL_BLUE, GL_ALPHA, GL_RGB, GL_BGR, GL_RGBA,
26 GL_BGRA, GL_LUMINANCE, or GL_LUMINANCE_ALPHA.
27 types The type of the data to be returned in values. Symbolic con‐
29 stants GL_UNSIGNED_BYTE, GL_BYTE, GL_BITMAP, GL_UNSIGNED_SHORT,
30 GL_SHORT, GL_UNSIGNED_INT, GL_INT, GL_FLOAT,
31 GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
32 GL_UNSIGNED_SHORT_5_6_5, GL_UNSIGNED_SHORT_5_6_5_REV,
33 GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
34 GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
35 GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
36 GL_UNSIGNED_INT_10_10_10_2, and GL_UNSIGNED_INT_2_10_10_10_REV
37 are accepted.
38 values A pointer to storage for the returned values.
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42 glGetMinmax returns the accumulated minimum and maximum pixel values
43 (computed on a per-component basis) in a one-dimensional image of width
44 2. The first set of return values are the minima, and the second set
45 of return values are the maxima. The of the return values is deter‐
46 mined by format, and their type is determined by types.
47 No pixel transfer operations are performed on the return values, but
49 pixel storage modes that are applicable to 1-dimensional images are
50 performed. Color components that are requested in the specified for‐
51 mat, but that are not included in the internal of the minmax table,
52 are returned as zero. The assignment of internal color components to
53 the components requested by format are as follows:
54 ─────────────────────────────────────────
57 Internal Component Resulting Component
58 ─────────────────────────────────────────
59 Red Red
60 Green Green
61 Blue Blue
62 Alpha Alpha
63 Luminance Red
64 ─────────────────────────────────────────
65 If reset is GL_TRUE, the minmax table entries corresponding to the
68 return values are reset to their initial values. Minimum and maximum
69 values that are not returned are not modified, even if reset is
70 GL_TRUE.
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73 glGetMinmax is present only if GL_ARB_imaging is returned when
74 glGetString is called with an argument of GL_EXTENSIONS.
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77 GL_INVALID_ENUM is generated if target is not GL_MINMAX.
78 GL_INVALID_ENUM is generated if format is not one of the allowable val‐
80 ues.
81 GL_INVALID_ENUM is generated if types is not one of the allowable val‐
83 ues.
84 GL_INVALID_OPERATION is generated if glGetMinmax is executed between
86 the execution of glBegin and the corresponding execution of glEnd.
87 GL_INVALID_OPERATION is generated if types is one of
89 GL_UNSIGNED_BYTE_3_3_2, GL_UNSIGNED_BYTE_2_3_3_REV,
90 GL_UNSIGNED_SHORT_5_6_5, or GL_UNSIGNED_SHORT_5_6_5_REV and format is
91 not GL_RGB.
92 GL_INVALID_OPERATION is generated if types is one of
94 GL_UNSIGNED_SHORT_4_4_4_4, GL_UNSIGNED_SHORT_4_4_4_4_REV,
95 GL_UNSIGNED_SHORT_5_5_5_1, GL_UNSIGNED_SHORT_1_5_5_5_REV,
96 GL_UNSIGNED_INT_8_8_8_8, GL_UNSIGNED_INT_8_8_8_8_REV,
97 GL_UNSIGNED_INT_10_10_10_2, or GL_UNSIGNED_INT_2_10_10_10_REV and for‐
98 mat is neither GL_RGBA nor GL_BGRA.
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101 glMinmax(3G), glResetMinmax(3G), glGetMinmaxParameter(3G)
102 GLGETMINMAX(3G)