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
|
<!DOCTYPE refentry [ <!ENTITY % mathent SYSTEM "math.ent"> %mathent; ]>
<!-- Converted by db4-upgrade version 1.1 -->
<refentry xmlns="http://docbook.org/ns/docbook" version="5.0" xml:id="glGetShaderPrecisionFormat">
<info>
<copyright>
<year>2010-2014</year>
<holder>Khronos Group</holder>
</copyright>
</info>
<refmeta>
<refentrytitle>glGetShaderPrecisionFormat</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glGetShaderPrecisionFormat</refname>
<refpurpose>retrieve the range and precision for numeric formats supported by the shader compiler</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glGetShaderPrecisionFormat</function></funcdef>
<paramdef>GLenum <parameter>shaderType</parameter></paramdef>
<paramdef>GLenum <parameter>precisionType</parameter></paramdef>
<paramdef>GLint *<parameter>range</parameter></paramdef>
<paramdef>GLint *<parameter>precision</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 xml:id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>shaderType</parameter></term>
<listitem>
<para>
Specifies the type of shader whose precision to query. <parameter>shaderType</parameter>
must be <constant>GL_VERTEX_SHADER</constant> or <constant>GL_FRAGMENT_SHADER</constant>.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>precisionType</parameter></term>
<listitem>
<para>
Specifies the numeric format whose precision and range to query.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>range</parameter></term>
<listitem>
<para>
Specifies the address of array of two integers into which encodings of the implementation's
numeric range are returned.
</para>
</listitem>
</varlistentry>
<varlistentry>
<term><parameter>precision</parameter></term>
<listitem>
<para>
Specifies the address of an integer into which the numeric precision of the implementation
is written.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 xml:id="description"><title>Description</title>
<para>
<function>glGetShaderPrecisionFormat</function> retrieves the numeric range and precision for
the implementation's representation of quantities in different numeric formats in specified
shader type. <parameter>shaderType</parameter> specifies the type of shader for which the numeric
precision and range is to be retrieved and must be one of <constant>GL_VERTEX_SHADER</constant>
or <constant>GL_FRAGMENT_SHADER</constant>. <parameter>precisionType</parameter> specifies the
numeric format to query and must be one of <constant>GL_LOW_FLOAT</constant>, <constant>GL_MEDIUM_FLOAT</constant>
<constant>GL_HIGH_FLOAT</constant>, <constant>GL_LOW_INT</constant>, <constant>GL_MEDIUM_INT</constant>,
or <constant>GL_HIGH_INT</constant>.
</para>
<para>
<parameter>range</parameter> points to an array of two integers into which the format's numeric range
will be returned. If min and max are the smallest values representable in the format, then the values
returned are defined to be: <parameter>range</parameter>[0] = floor(log2(|min|)) and
<parameter>range</parameter>[1] = floor(log2(|max|)).
</para>
<para>
<parameter>precision</parameter> specifies the address of an integer into which will be written
the log2 value of the number of bits of precision of the format. If the smallest representable
value greater than 1 is 1 + <emphasis>eps</emphasis>, then the integer addressed by <parameter>precision</parameter>
will contain floor(-log2(eps)).
</para>
</refsect1>
<refsect1 xml:id="errors"><title>Errors</title>
<para>
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>shaderType</parameter> or
<parameter>precisionType</parameter> is not an accepted value.
</para>
</refsect1>
<refsect1 xml:id="versions"><title>Version Support</title>
<informaltable>
<tgroup cols="13" align="left">
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apifunchead.xml" xpointer="xpointer(/*/*)"/>
<tbody>
<row>
<entry><function>glGetShaderPrecisionFormat</function></entry>
<xi:include xmlns:xi="http://www.w3.org/2001/XInclude" href="apiversion.xml" xpointer="xpointer(/*/*[@role='41']/*)"/>
</row>
</tbody>
</tgroup>
</informaltable>
</refsect1>
<refsect1 xml:id="seealso"><title>See Also</title>
<!-- TBD -->
</refsect1>
<refsect1 xml:id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"/> 2010-2014 Khronos Group.
This material may be distributed subject to the terms and conditions set forth in
the Open Publication License, v 1.0, 8 June 1999.
<link xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="http://opencontent.org/openpub/">http://opencontent.org/openpub/</link>.
</para>
</refsect1>
</refentry>
|
