Opentk/Source/Bind/Specifications/Docs/glMinSampleShading.xml

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<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
<refentry id="glMinSampleShading">
<refentryinfo>
<copyright>
<year>2011-2013</year>
<holder>Khronos Group.</holder>
</copyright>
</refentryinfo>
<refmeta>
<refentrytitle>glMinSampleShading</refentrytitle>
<manvolnum>3G</manvolnum>
</refmeta>
<refnamediv>
<refname>glMinSampleShading</refname>
<refpurpose>specifies minimum rate at which sample shaing takes place</refpurpose>
</refnamediv>
<refsynopsisdiv><title>C Specification</title>
<funcsynopsis>
<funcprototype>
<funcdef>void <function>glMinSampleShading</function></funcdef>
<paramdef>GLfloat <parameter>value</parameter></paramdef>
</funcprototype>
</funcsynopsis>
</refsynopsisdiv>
<refsect1 id="parameters"><title>Parameters</title>
<variablelist>
<varlistentry>
<term><parameter>value</parameter></term>
<listitem>
<para>
Specifies the rate at which samples are shaded within each covered pixel.
</para>
</listitem>
</varlistentry>
</variablelist>
</refsect1>
<refsect1 id="description"><title>Description</title>
<para>
<function>glMinSampleShading</function> specifies the rate at which samples are shaded within
a covered pixel. Sample-rate shading is enabled by calling <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>
with the parameter <constant>GL_SAMPLE_SHADING</constant>. If <constant>GL_MULTISAMPLE</constant>
or <constant>GL_SAMPLE_SHADING</constant> is disabled, sample shading has no effect.
Otherwise, an implementation must provide at least as many unique color values for
each covered fragment as specified by <parameter>value</parameter> times <parameter>samples</parameter> where
<parameter>samples</parameter> is the value of <constant>GL_SAMPLES</constant> for the current
framebuffer. At least 1 sample for each covered fragment is generated.
</para>
<para>
A <parameter>value</parameter> of 1.0 indicates that each sample in the framebuffer should be
indpendently shaded. A <parameter>value</parameter> of 0.0 effectively allows the GL to ignore
sample rate shading. Any value between 0.0 and 1.0 allows the GL to shade only a subset
of the total samples within each covered fragment. Which samples are shaded and the algorithm
used to select that subset of the fragment's samples is implementation dependent.
</para>
</refsect1>
<refsect1 id="notes"><title>Notes</title>
<para>
The type of the <parameter>value</parameter> parameter was
changed from GLclampf to GLfloat. This change is transparent
to user code and is described in detail on the
<citerefentry><refentrytitle>removedTypes</refentrytitle></citerefentry>
page.
</para>
</refsect1>
<refsect1 id="errors"><title>Errors</title>
<para>
None.
</para>
</refsect1>
<refsect1 id="associatedgets"><title>Associated Gets</title>
<para>
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MIN_SAMPLE_SHADING</constant>.
</para>
<para>
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_SAMPLES</constant>.
</para>
</refsect1>
<refsect1 id="seealso"><title>See Also</title>
<para>
<citerefentry><refentrytitle>removedTypes</refentrytitle></citerefentry>
</para>
</refsect1>
<refsect1 id="Copyright"><title>Copyright</title>
<para>
Copyright <trademark class="copyright"></trademark> 2011-2013 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.
<ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.
</para>
</refsect1>
</refentry>