1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
|
'\" t
'\"! tbl | mmdoc
'\"macro stdmacro
.ds Vn Version 1.2
.ds Dt 24 September 1999
.ds Re Release 1.2.1
.ds Dp Jan 14 18:30
.ds Dm 01 getminmax
.ds Xs 43140 6 getminmax.gl
.TH GLGETMINMAX 3G
.SH NAME
.B "glGetMinmax
\- get minimum and maximum pixel values
.SH C SPECIFICATION
void \f3glGetMinmax\fP(
GLenum \fItarget\fP,
.nf
.ta \w'\f3void \fPglGetMinmax( 'u
GLboolean \fIreset\fP,
GLenum \fIformat\fP,
GLenum \fItypes\fP,
GLvoid \fI*values\fP )
.fi
.SH PARAMETERS
.TP \w'\f2target\fP\ \ 'u
\f2target\fP
Must be
\%\f3GL_MINMAX\fP.
.TP
\f2reset\fP
If \%\f3GL_TRUE\fP, all entries in the minmax table that are actually
returned are reset to their initial values. (Other entries are unaltered.)
If \%\f3GL_FALSE\fP, the minmax table is unaltered.
.TP
\f2format\fP
The of the data to be returned in \f2values\fP.
Must be one of
\%\f3GL_RED\fP,
\%\f3GL_GREEN\fP,
\%\f3GL_BLUE\fP,
\%\f3GL_ALPHA\fP,
\%\f3GL_RGB\fP,
\%\f3GL_BGR\fP,
\%\f3GL_RGBA\fP,
\%\f3GL_BGRA\fP,
\%\f3GL_LUMINANCE\fP, or
\%\f3GL_LUMINANCE_ALPHA\fP.
.TP
\f2types\fP
The type of the data to be returned in \f2values\fP.
Symbolic constants
\%\f3GL_UNSIGNED_BYTE\fP,
\%\f3GL_BYTE\fP,
\%\f3GL_BITMAP\fP,
\%\f3GL_UNSIGNED_SHORT\fP,
\%\f3GL_SHORT\fP,
\%\f3GL_UNSIGNED_INT\fP,
\%\f3GL_INT\fP,
\%\f3GL_FLOAT\fP,
\%\f3GL_UNSIGNED_BYTE_3_3_2\fP,
\%\f3GL_UNSIGNED_BYTE_2_3_3_REV\fP,
\%\f3GL_UNSIGNED_SHORT_5_6_5\fP,
\%\f3GL_UNSIGNED_SHORT_5_6_5_REV\fP,
\%\f3GL_UNSIGNED_SHORT_4_4_4_4\fP,
\%\f3GL_UNSIGNED_SHORT_4_4_4_4_REV\fP,
\%\f3GL_UNSIGNED_SHORT_5_5_5_1\fP,
\%\f3GL_UNSIGNED_SHORT_1_5_5_5_REV\fP,
\%\f3GL_UNSIGNED_INT_8_8_8_8\fP,
\%\f3GL_UNSIGNED_INT_8_8_8_8_REV\fP,
\%\f3GL_UNSIGNED_INT_10_10_10_2\fP, and
\%\f3GL_UNSIGNED_INT_2_10_10_10_REV\fP
are accepted.
.TP
\f2values\fP
A pointer to storage for the returned values.
.SH DESCRIPTION
\%\f3glGetMinmax\fP returns the accumulated minimum and maximum pixel values (computed on a
per-component basis) in a one-dimensional image of width 2. The first set
of return values are the minima, and the second set of return values
are the maxima.
The of the return values is determined by \f2format\fP, and their type is
determined by \f2types\fP.
.PP
No pixel transfer operations are performed on the return values, but pixel
storage modes that are applicable to 1-dimensional images are performed.
Color components that are requested in the specified \f2format\fP, but that
are not included in the internal of the minmax table, are
returned as zero. The assignment of internal color components to the
components requested by \f2format\fP are as follows:
.sp
.TS
center;
lb lb
l l.
_
Internal Component Resulting Component
_
Red Red
Green Green
Blue Blue
Alpha Alpha
Luminance Red
_
.TE
.PP
If \f2reset\fP is \%\f3GL_TRUE\fP, the minmax table entries corresponding
to the return values are reset to their initial
values. Minimum and maximum values that are not returned are not
modified, even if \f2reset\fP is \%\f3GL_TRUE\fP.
.SH NOTES
\%\f3glGetMinmax\fP is present only if \%\f3GL_ARB_imaging\fP is returned when \%\f3glGetString\fP
is called with an argument of \%\f3GL_EXTENSIONS\fP.
.SH ERRORS
\%\f3GL_INVALID_ENUM\fP is generated if \f2target\fP is not \%\f3GL_MINMAX\fP.
.P
\%\f3GL_INVALID_ENUM\fP is generated if \f2format\fP is not one of the allowable
values.
.P
\%\f3GL_INVALID_ENUM\fP is generated if \f2types\fP is not one of the allowable
values.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \%\f3glGetMinmax\fP is executed
between the execution of \%\f3glBegin\fP and the corresponding
execution of \%\f3glEnd\fP.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \f2types\fP is one of
\%\f3GL_UNSIGNED_BYTE_3_3_2\fP,
\%\f3GL_UNSIGNED_BYTE_2_3_3_REV\fP,
\%\f3GL_UNSIGNED_SHORT_5_6_5\fP, or
\%\f3GL_UNSIGNED_SHORT_5_6_5_REV\fP
and \f2format\fP is not \%\f3GL_RGB\fP.
.P
\%\f3GL_INVALID_OPERATION\fP is generated if \f2types\fP is one of
\%\f3GL_UNSIGNED_SHORT_4_4_4_4\fP,
\%\f3GL_UNSIGNED_SHORT_4_4_4_4_REV\fP,
\%\f3GL_UNSIGNED_SHORT_5_5_5_1\fP,
\%\f3GL_UNSIGNED_SHORT_1_5_5_5_REV\fP,
\%\f3GL_UNSIGNED_INT_8_8_8_8\fP,
\%\f3GL_UNSIGNED_INT_8_8_8_8_REV\fP,
\%\f3GL_UNSIGNED_INT_10_10_10_2\fP, or
\%\f3GL_UNSIGNED_INT_2_10_10_10_REV\fP
and \f2format\fP is neither \%\f3GL_RGBA\fP nor \%\f3GL_BGRA\fP.
.SH SEE ALSO
\%\f3glMinmax(3G)\fP,
\%\f3glResetMinmax(3G)\fP,
\%\f3glGetMinmaxParameter(3G)\fP
|
