<?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="glBlendFuncSeparate">
    <refmeta>
        <refmetainfo>
            <copyright>
                <year>1991-2006</year>
                <holder>Silicon Graphics, Inc.</holder>
            </copyright>
        </refmetainfo>
        <refentrytitle>glBlendFuncSeparate</refentrytitle>
        <manvolnum>3G</manvolnum>
    </refmeta>
    <refnamediv>
        <refname>glBlendFuncSeparate</refname>
        <refpurpose>specify pixel arithmetic for RGB and alpha components separately</refpurpose>
    </refnamediv>
    <refsynopsisdiv><title>C Specification</title>
        <funcsynopsis>
            <funcprototype>
                <funcdef>void <function>glBlendFuncSeparate</function></funcdef>
                <paramdef>GLenum <parameter>srcRGB</parameter></paramdef>
                <paramdef>GLenum <parameter>dstRGB</parameter></paramdef>
                <paramdef>GLenum <parameter>srcAlpha</parameter></paramdef>
                <paramdef>GLenum <parameter>dstAlpha</parameter></paramdef>
            </funcprototype>
        </funcsynopsis>
    </refsynopsisdiv>
    <!-- eqn: ignoring delim $$ -->
    <refsect1 id="parameters"><title>Parameters</title>
        <variablelist>
        <varlistentry>
            <term><parameter>srcRGB</parameter></term>
            <listitem>
                <para>
                    Specifies how the red, green, and blue blending factors are computed.
                    The following symbolic constants are accepted:
                    <constant>GL_ZERO</constant>,
                    <constant>GL_ONE</constant>,
                    <constant>GL_SRC_COLOR</constant>,
                    <constant>GL_ONE_MINUS_SRC_COLOR</constant>,
                    <constant>GL_DST_COLOR</constant>,
                    <constant>GL_ONE_MINUS_DST_COLOR</constant>,
                    <constant>GL_SRC_ALPHA</constant>,
                    <constant>GL_ONE_MINUS_SRC_ALPHA</constant>,
                    <constant>GL_DST_ALPHA</constant>,
                    <constant>GL_ONE_MINUS_DST_ALPHA</constant>,
                    <constant>GL_CONSTANT_COLOR</constant>,
                    <constant>GL_ONE_MINUS_CONSTANT_COLOR</constant>,
                    <constant>GL_CONSTANT_ALPHA</constant>,
                    <constant>GL_ONE_MINUS_CONSTANT_ALPHA</constant>, and
                    <constant>GL_SRC_ALPHA_SATURATE</constant>.
                    The initial value is <constant>GL_ONE</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>dstRGB</parameter></term>
            <listitem>
                <para>
                    Specifies how the red, green, and blue destination blending factors are
                    computed. The following symbolic constants are accepted:
                    <constant>GL_ZERO</constant>,
                    <constant>GL_ONE</constant>,
                    <constant>GL_SRC_COLOR</constant>,
                    <constant>GL_ONE_MINUS_SRC_COLOR</constant>,
                    <constant>GL_DST_COLOR</constant>,
                    <constant>GL_ONE_MINUS_DST_COLOR</constant>,
                    <constant>GL_SRC_ALPHA</constant>,
                    <constant>GL_ONE_MINUS_SRC_ALPHA</constant>,
                    <constant>GL_DST_ALPHA</constant>,
                    <constant>GL_ONE_MINUS_DST_ALPHA</constant>.
                    <constant>GL_CONSTANT_COLOR</constant>,
                    <constant>GL_ONE_MINUS_CONSTANT_COLOR</constant>,
                    <constant>GL_CONSTANT_ALPHA</constant>, and
                    <constant>GL_ONE_MINUS_CONSTANT_ALPHA</constant>.
                    The initial value is <constant>GL_ZERO</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>srcAlpha</parameter></term>
            <listitem>
                <para>
                    Specified how the alpha source blending factor is computed.  The same
                    symbolic constants are accepted as for <parameter>srcRGB</parameter>.
                    The initial value is <constant>GL_ONE</constant>.
                </para>
            </listitem>
        </varlistentry>
        <varlistentry>
            <term><parameter>dstAlpha</parameter></term>
            <listitem>
                <para>
                    Specified how the alpha destination blending factor is computed.  The same
                    symbolic constants are accepted as for <parameter>dstRGB</parameter>.
                    The initial value is <constant>GL_ZERO</constant>.
                </para>
            </listitem>
        </varlistentry>
        </variablelist>
    </refsect1>
    <refsect1 id="description"><title>Description</title>
        <para>
            In RGBA mode, pixels can be drawn using a function that blends
            the incoming (source) RGBA values with the RGBA values
            that are already in the frame buffer (the destination values).
            Blending is initially disabled.
            Use <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry> and <citerefentry><refentrytitle>glDisable</refentrytitle></citerefentry> with argument <constant>GL_BLEND</constant>
            to enable and disable blending.
        </para>
        <para>
            <function>glBlendFuncSeparate</function> defines the operation of blending when it is enabled.
            <parameter>srcRGB</parameter> specifies which method is used to scale the
            source RGB-color components.
            <parameter>dstRGB</parameter> specifies which method is used to scale the
            destination RGB-color components.
            Likewise, <parameter>srcAlpha</parameter> specifies which method is used to scale the source alpha
            color component, and <parameter>dstAlpha</parameter> specifies which method is used to scale the
            destination alpha component.
            The possible methods are described in the following table.
            Each method defines four scale factors,
            one each for red, green, blue, and alpha.
        </para>
        <para>
            In the table and in subsequent equations, source and destination
            color components are referred to as
            <inlineequation><mml:math>
                <!-- eqn: ( R sub s , G sub s , B sub s , A sub s ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                    <mml:mi mathvariant="italic">s</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                    <mml:mi mathvariant="italic">s</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                    <mml:mi mathvariant="italic">s</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                    <mml:mi mathvariant="italic">s</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>
            and
            <inlineequation><mml:math>
                <!-- eqn: ( R sub d , G sub d , B sub d , A sub d ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                    <mml:mi mathvariant="italic">d</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                    <mml:mi mathvariant="italic">d</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                    <mml:mi mathvariant="italic">d</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                    <mml:mi mathvariant="italic">d</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>.
            The color specified by <citerefentry><refentrytitle>glBlendColor</refentrytitle></citerefentry> is referred to as
            <inlineequation><mml:math>
                <!-- eqn: ( R sub c , G sub c , B sub c , A sub c ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                    <mml:mi mathvariant="italic">c</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                    <mml:mi mathvariant="italic">c</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                    <mml:mi mathvariant="italic">c</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                    <mml:mi mathvariant="italic">c</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>.
            They are understood to have integer values between 0 and
            <inlineequation><mml:math>
                <!-- eqn: ( k sub R , k sub G , k sub B , k sub A ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                    <mml:mi mathvariant="italic">R</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                    <mml:mi mathvariant="italic">G</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                    <mml:mi mathvariant="italic">B</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                    <mml:mi mathvariant="italic">A</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>,
            where
        </para>
        <para>
            <para>
                <inlineequation><mml:math>
                    <!-- eqn: k sub c  =  2 sup {m sub c} - 1:-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                        <mml:mi mathvariant="italic">c</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:msup><mml:mn>2</mml:mn>
                            <mml:mfenced open="" close="">
                                <mml:msub><mml:mi mathvariant="italic">m</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                            </mml:mfenced>
                            </mml:msup>
                            <mml:mo>-</mml:mo>
                            <mml:mn>1</mml:mn>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
            </para>
        </para>
        <para>
            and
            <inlineequation><mml:math>
                <!-- eqn: ( m sub R , m sub G , m sub B , m sub A ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">m</mml:mi>
                    <mml:mi mathvariant="italic">R</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">m</mml:mi>
                    <mml:mi mathvariant="italic">G</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">m</mml:mi>
                    <mml:mi mathvariant="italic">B</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">m</mml:mi>
                    <mml:mi mathvariant="italic">A</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>
            is the number of red,
            green,
            blue,
            and alpha bitplanes.
        </para>
        <para>
            Source and destination scale factors are referred to as
            <inlineequation><mml:math>
                <!-- eqn: ( s sub R , s sub G , s sub B , s sub A ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                    <mml:mi mathvariant="italic">R</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                    <mml:mi mathvariant="italic">G</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                    <mml:mi mathvariant="italic">B</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                    <mml:mi mathvariant="italic">A</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>
            and
            <inlineequation><mml:math>
                <!-- eqn: ( d sub R , d sub G , d sub B , d sub A ):-->
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                    <mml:mi mathvariant="italic">R</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                    <mml:mi mathvariant="italic">G</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                    <mml:mi mathvariant="italic">B</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                    <mml:mi mathvariant="italic">A</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math></inlineequation>.
            All scale factors have range 
            <inlineequation><mml:math>
                <!-- eqn: [0,1]:-->
                <mml:mfenced open="[" close="]">
                    <mml:mn>0</mml:mn>
                    <mml:mn>1</mml:mn>
                </mml:mfenced>
            </mml:math></inlineequation>.
        </para>
        <para>
        </para>
        <informaltable frame="topbot">
            <tgroup cols="3" align="left">
                <colspec colwidth="3*" />
                <colspec colwidth="2*" />
                <colspec colwidth="1*" />
                <thead>
                    <row>
                        <entry rowsep="1" align="left"><emphasis role="bold">
                        Parameter
                        </emphasis></entry>
                        <entry rowsep="1" align="left"><emphasis role="bold">
                        RGB Factor
                        </emphasis></entry>
                        <entry rowsep="1" align="left"><emphasis role="bold">
                        Alpha Factor
                        </emphasis></entry>
                    </row>
                </thead>
                <tbody>
                    <row>
                        <entry align="left">
                        <constant>GL_ZERO</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 0,  0,  0 ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mn>0</mml:mn>
                                <mml:mn>0</mml:mn>
                                <mml:mn>0</mml:mn>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 0:-->
                            <mml:mn>0</mml:mn>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mn>1</mml:mn>
                                <mml:mn>1</mml:mn>
                                <mml:mn>1</mml:mn>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1:-->
                            <mml:mn>1</mml:mn>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_SRC_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( R sub s / k sub R ,  G sub s / k sub G ,  B sub s / k sub B ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">R</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">G</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">B</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub s / k sub A:-->
                            <mml:mfrac>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">s</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">A</mml:mi>
                                </mml:msub>
                            </mml:mfrac>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_SRC_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1,  1 )  -  ( R sub s / k sub R ,  G sub s / k sub G ,  B sub s / k sub B ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">R</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">G</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">B</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1  - A sub s / k sub A:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_DST_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( R sub d / k sub R ,  G sub d / k sub G ,  B sub d / k sub B ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">R</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">G</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">B</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub d / k sub A:-->
                            <mml:mfrac>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">d</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">A</mml:mi>
                                </mml:msub>
                            </mml:mfrac>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_DST_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 )  -  ( R sub d / k sub R ,  G sub d / k sub G ,  B sub d / k sub B ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">R</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">G</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">B</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1 - A sub d / k sub A:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_SRC_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( A sub s / k sub A ,  A sub s / k sub A ,  A sub s / k sub A ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub s / k sub A:-->
                            <mml:mfrac>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">s</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">A</mml:mi>
                                </mml:msub>
                            </mml:mfrac>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_SRC_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 )  -  ( A sub s / k sub A ,  A sub s / k sub A ,  A sub s / k sub A ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">s</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1 - A sub s / k sub A:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_DST_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( A sub d / k sub A ,  A sub d / k sub A ,  A sub d / k sub A ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub d / k sub A:-->
                            <mml:mfrac>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">d</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">A</mml:mi>
                                </mml:msub>
                            </mml:mfrac>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_DST_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 )  -  ( A sub d / k sub A ,  A sub d / k sub A ,  A sub d / k sub A ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                    <mml:mfrac>
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                        <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                        <mml:mi mathvariant="italic">A</mml:mi>
                                        </mml:msub>
                                    </mml:mfrac>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1 - A sub d / k sub A:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:mfrac>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mfrac>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_CONSTANT_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( R sub c,  G sub c,  B sub c ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub c:-->
                            <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                            <mml:mi mathvariant="italic">c</mml:mi>
                            </mml:msub>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_CONSTANT_COLOR</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 )  -  ( R sub c,  G sub c,  B sub c ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1  -  A sub c:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_CONSTANT_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( A sub c,  A sub c,  A sub c ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: A sub c:-->
                            <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                            <mml:mi mathvariant="italic">c</mml:mi>
                            </mml:msub>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_ONE_MINUS_CONSTANT_ALPHA</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( 1,  1,  1 )  -  ( A sub c,  A sub c,  A sub c ):-->
                            <mml:mrow>
                                <mml:mfenced open="(" close=")">
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                    <mml:mn>1</mml:mn>
                                </mml:mfenced>
                                <mml:mo>-</mml:mo>
                                <mml:mfenced open="(" close=")">
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">c</mml:mi>
                                    </mml:msub>
                                </mml:mfenced>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1  -  A sub c:-->
                            <mml:mrow>
                                <mml:mn>1</mml:mn>
                                <mml:mo>-</mml:mo>
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">c</mml:mi>
                                </mml:msub>
                            </mml:mrow>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                    <row>
                        <entry align="left">
                        <constant>GL_SRC_ALPHA_SATURATE</constant>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: ( i,  i,  i ):-->
                            <mml:mfenced open="(" close=")">
                                <mml:mi mathvariant="italic">i</mml:mi>
                                <mml:mi mathvariant="italic">i</mml:mi>
                                <mml:mi mathvariant="italic">i</mml:mi>
                            </mml:mfenced>
                        </mml:math></inlineequation>
                        </entry>
                        <entry align="left">
                        <inlineequation><mml:math>
                            <!-- eqn: 1:-->
                            <mml:mn>1</mml:mn>
                        </mml:math></inlineequation>
                        </entry>
                    </row>
                </tbody>
            </tgroup>
        </informaltable>
        <para>
            In the table,
        </para>
        <para>
            <para>
                <inlineequation><mml:math>
                    <!-- eqn: i  =   min (A sub s , 1 - {A sub d}):-->
                    <mml:mrow>
                        <mml:mi mathvariant="italic">i</mml:mi>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:mi mathvariant="italic">min</mml:mi>
                            <mml:mo>&af;</mml:mo>
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                <mml:mi mathvariant="italic">s</mml:mi>
                                </mml:msub>
                                <mml:mrow>
                                    <mml:mn>1</mml:mn>
                                    <mml:mo>-</mml:mo>
                                    <mml:mfenced open="" close="">
                                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                        <mml:mi mathvariant="italic">d</mml:mi>
                                        </mml:msub>
                                    </mml:mfenced>
                                </mml:mrow>
                            </mml:mfenced>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
            </para>
        </para>
        <para>
            To determine the blended RGBA values of a pixel when drawing in RGBA mode,
            the system uses the following equations:
        </para>
        <para>
            <para>
                <inlineequation><mml:math>
                    <!-- eqn: R sub d  =      min ( k sub R,  R sub s s sub R + R sub d d sub R ):-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:mi mathvariant="italic">min</mml:mi>
                            <mml:mo>&af;</mml:mo>
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">R</mml:mi>
                                </mml:msub>
                                <mml:mrow>
                                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                                    <mml:mi mathvariant="italic">R</mml:mi>
                                    </mml:msub>
                                    <mml:mo>+</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                                    <mml:mi mathvariant="italic">R</mml:mi>
                                    </mml:msub>
                                </mml:mrow>
                            </mml:mfenced>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: G sub d  =    min ( k sub G,  G sub s s sub G + G sub d d sub G ):-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:mi mathvariant="italic">min</mml:mi>
                            <mml:mo>&af;</mml:mo>
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">G</mml:mi>
                                </mml:msub>
                                <mml:mrow>
                                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                                    <mml:mi mathvariant="italic">G</mml:mi>
                                    </mml:msub>
                                    <mml:mo>+</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                                    <mml:mi mathvariant="italic">G</mml:mi>
                                    </mml:msub>
                                </mml:mrow>
                            </mml:mfenced>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: B sub d  =    min ( k sub B,  B sub s s sub B + B sub d d sub B ):-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:mi mathvariant="italic">min</mml:mi>
                            <mml:mo>&af;</mml:mo>
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">B</mml:mi>
                                </mml:msub>
                                <mml:mrow>
                                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                                    <mml:mi mathvariant="italic">B</mml:mi>
                                    </mml:msub>
                                    <mml:mo>+</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                                    <mml:mi mathvariant="italic">B</mml:mi>
                                    </mml:msub>
                                </mml:mrow>
                            </mml:mfenced>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: A sub d  =    min ( k sub A,  A sub s s sub A + A sub d d sub A ):-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:mrow>
                            <mml:mi mathvariant="italic">min</mml:mi>
                            <mml:mo>&af;</mml:mo>
                            <mml:mfenced open="(" close=")">
                                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                                <mml:mi mathvariant="italic">A</mml:mi>
                                </mml:msub>
                                <mml:mrow>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">s</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                    <mml:mo>+</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                    <mml:mi mathvariant="italic">d</mml:mi>
                                    </mml:msub>
                                    <mml:mo>&it;</mml:mo>
                                    <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
                                    <mml:mi mathvariant="italic">A</mml:mi>
                                    </mml:msub>
                                </mml:mrow>
                            </mml:mfenced>
                        </mml:mrow>
                    </mml:mrow>
                </mml:math></inlineequation>
            </para>
        </para>
        <para>
            Despite the apparent precision of the above equations, blending arithmetic
            is not exactly specified, because blending operates with imprecise integer
            color values.  However, a blend factor that should be equal to 1 is
            guaranteed not to modify its multiplicand, and a blend factor equal to 0
            reduces its multiplicand to 0.  For example, when <parameter>srcRGB</parameter> is
            <constant>GL_SRC_ALPHA</constant>, <parameter>dstRGB</parameter> is <constant>GL_ONE_MINUS_SRC_ALPHA</constant>, and 
            <inlineequation><mml:math>
                <!-- eqn: A sub s:-->
                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                <mml:mi mathvariant="italic">s</mml:mi>
                </mml:msub>
            </mml:math></inlineequation>
            is
            equal to 
            <inlineequation><mml:math>
                <!-- eqn: k sub A:-->
                <mml:msub><mml:mi mathvariant="italic">k</mml:mi>
                <mml:mi mathvariant="italic">A</mml:mi>
                </mml:msub>
            </mml:math></inlineequation>,
            the equations reduce to simple replacement:
        </para>
        <para>
            <para>
                <inlineequation><mml:math>
                    <!-- eqn: R sub d  =      R sub s:-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                        <mml:mi mathvariant="italic">s</mml:mi>
                        </mml:msub>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: G sub d  =    G sub s:-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                        <mml:mi mathvariant="italic">s</mml:mi>
                        </mml:msub>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: B sub d  =    B sub s:-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                        <mml:mi mathvariant="italic">s</mml:mi>
                        </mml:msub>
                    </mml:mrow>
                </mml:math></inlineequation>
                <inlineequation><mml:math>
                    <!-- eqn: A sub d  =    A sub s:-->
                    <mml:mrow>
                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                        <mml:mi mathvariant="italic">d</mml:mi>
                        </mml:msub>
                        <mml:mo>=</mml:mo>
                        <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                        <mml:mi mathvariant="italic">s</mml:mi>
                        </mml:msub>
                    </mml:mrow>
                </mml:math></inlineequation>
            </para>
        </para>
        <para>
        </para>
    </refsect1>
    <refsect1 id="notes"><title>Notes</title>
        <para>
            <function>glBlendFuncSeparate</function> is available only if the GL version is 1.4 or greater.
        </para>
        <para>
            Incoming (source) alpha is correctly thought of as a material opacity,
            ranging from 1.0 
            (<inlineequation><mml:math>
                <!-- eqn: K sub A:-->
                <mml:msub><mml:mi mathvariant="italic">K</mml:mi>
                <mml:mi mathvariant="italic">A</mml:mi>
                </mml:msub>
            </mml:math></inlineequation>),
            representing complete opacity,
            to 0.0 (0), representing complete
            transparency.
        </para>
        <para>
            When more than one color buffer is enabled for drawing,
            the GL performs blending separately for each enabled buffer,
            using the contents of that buffer for destination color.
            (See <citerefentry><refentrytitle>glDrawBuffer</refentrytitle></citerefentry>.)
        </para>
        <para>
            Blending affects only RGBA rendering.
            It is ignored by color index renderers.
        </para>
        <para>
            <constant>GL_CONSTANT_COLOR</constant>, <constant>GL_ONE_MINUS_CONSTANT_COLOR</constant>,
            <constant>GL_CONSTANT_ALPHA</constant>, <constant>GL_ONE_MINUS_CONSTANT_ALPHA</constant> are available only
            if the GL version is 1.4 or greater or if the <code>ARB_imaging</code> is
            supported by your implementation.
        </para>
        <para>
            <constant>GL_SRC_COLOR</constant> and <constant>GL_ONE_MINUS_SRC_COLOR</constant> are valid only for
            <parameter>srcRGB</parameter> if the GL version is 1.4 or greater.
        </para>
        <para>
            <constant>GL_DST_COLOR</constant> and <constant>GL_ONE_MINUS_DST_COLOR</constant> are valid only for
            <parameter>dstRGB</parameter> if the GL version is 1.4 or greater.
        </para>
    </refsect1>
    <refsect1 id="errors"><title>Errors</title>
        <para>
            <constant>GL_INVALID_ENUM</constant> is generated if either <parameter>srcRGB</parameter> or <parameter>dstRGB</parameter> is not an
            accepted value.
        </para>
        <para>
            <constant>GL_INVALID_OPERATION</constant> is generated if <function>glBlendFuncSeparate</function>
            is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
            and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
        </para>
    </refsect1>
    <refsect1 id="associatedgets"><title>Associated Gets</title>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_BLEND_SRC_RGB</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_BLEND_SRC_ALPHA</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_BLEND_DST_RGB</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_BLEND_DST_ALPHA</constant>
        </para>
        <para>
            <citerefentry><refentrytitle>glIsEnabled</refentrytitle></citerefentry> with argument <constant>GL_BLEND</constant>
        </para>
        <para>
        </para>
    </refsect1>
    <refsect1 id="seealso"><title>See Also</title>
        <para>
            <citerefentry><refentrytitle>glAlphaFunc</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glBlendColor</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glBlendFunc</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glBlendEquation</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glClear</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glDrawBuffer</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glEnable</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glLogicOp</refentrytitle></citerefentry>,
            <citerefentry><refentrytitle>glStencilFunc</refentrytitle></citerefentry>
        </para>
    </refsect1>
    <refsect1 id="Copyright"><title>Copyright</title>
        <para>
            Copyright <trademark class="copyright"></trademark> 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
        </para>
    </refsect1>
</refentry>
