<?xml version="1.0" encoding="UTF-8"?>
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<?xml-stylesheet type="text/xsl" href="mathml.xsl"?><html xmlns="http://www.w3.org/1999/xhtml" xmlns:pref="http://www.w3.org/2002/Math/preference" pref:renderer="mathplayer-dl"><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /><title>glBlendEquation</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glBlendEquation"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glBlendEquation — specify the equation used for both the RGB blend equation and the Alpha blend equation</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" class="funcprototype-table" summary="Function synopsis" style="cellspacing: 0; cellpadding: 0;"><tr><td><code class="funcdef">void <strong class="fsfunc">glBlendEquation</strong>(</code></td><td>GLenum <var class="pdparam">mode</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl class="variablelist"><dt><span class="term"><em class="parameter"><code>mode</code></em></span></dt><dd><p>
                    specifies how source and destination colors are combined.
                    It must be <code class="constant">GL_FUNC_ADD</code>, <code class="constant">GL_FUNC_SUBTRACT</code>,
                    <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>, <code class="constant">GL_MIN</code>, <code class="constant">GL_MAX</code>.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            The blend equations determine how a new pixel (the ''source'' color)
            is combined with a pixel already in the framebuffer (the ''destination''
            color).  This function sets both the RGB blend equation and the alpha 
            blend equation to a single equation.
        </p><p>
            These equations use the source and destination blend factors
            specified by either <a class="citerefentry" href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a> or
            <a class="citerefentry" href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>.
            See <a class="citerefentry" href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a> or <a class="citerefentry" href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>
            for a description of the various blend factors.
        </p><p>
            In the equations that follow, source and destination
            color components are referred to as
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <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>
            and
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <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>,
            respectively.
            The result color is referred to as
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mfenced open="(" close=")">
                    <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                    <mml:mi mathvariant="italic">r</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                    <mml:mi mathvariant="italic">r</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                    <mml:mi mathvariant="italic">r</mml:mi>
                    </mml:msub>
                    <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                    <mml:mi mathvariant="italic">r</mml:mi>
                    </mml:msub>
                </mml:mfenced>
            </mml:math>.
            The source and destination blend factors are denoted
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <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>
            and
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <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>,
            respectively.
            For these equations all color components are understood to have values
            in the range 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mfenced open="[" close="]">
                    <mml:mn>0</mml:mn>
                    <mml:mn>1</mml:mn>
                </mml:mfenced>
            </mml:math>.

        </p><div class="informaltable"><table border="1"><colgroup><col align="left" /><col align="left" /><col align="left" /></colgroup><thead><tr><th align="left"><span class="bold"><strong>
                        Mode
                        </strong></span></th><th align="left"><span class="bold"><strong>
                        RGB Components
                        </strong></span></th><th align="left"><span class="bold"><strong>
                        Alpha Component
                        </strong></span></th></tr></thead><tbody><tr><td align="left">
                        <code class="constant">GL_FUNC_ADD</code>
                        </td><td align="left">
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Rr</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">R</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">R</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Gr</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">G</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">G</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Br</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">B</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">B</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        </td><td align="left">
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Ar</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">A</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">A</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        </td></tr><tr><td align="left">
                        <code class="constant">GL_FUNC_SUBTRACT</code>
                        </td><td align="left">
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Rr</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">R</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">R</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Gr</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">G</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">G</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Br</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">B</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">B</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        </td><td align="left">
                        <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mrow>
                                <mml:mi mathvariant="italic">Ar</mml:mi>
                                <mml:mo>=</mml:mo>
                                <mml:mrow>
									<mml:msub><mml:mi mathvariant="italic">A</mml:mi>
									<mml:mi mathvariant="italic">s</mml:mi>
									</mml:msub>
									<mml:mo>⁢</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>⁢</mml:mo>
									<mml:msub><mml:mi mathvariant="italic">d</mml:mi>
									<mml:mi mathvariant="italic">A</mml:mi>
									</mml:msub>
                                </mml:mrow>
                            </mml:mrow>
                        </mml:math></div>
                        </td></tr><tr><td align="left">
                        <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Rr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <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">d</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">s</mml:mi>
										</mml:msub>
										<mml:mo>⁢</mml:mo>
										<mml:msub><mml:mi mathvariant="italic">s</mml:mi>
										<mml:mi mathvariant="italic">R</mml:mi>
										</mml:msub>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Gr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <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">d</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">s</mml:mi>
										</mml:msub>
										<mml:mo>⁢</mml:mo>
										<mml:msub><mml:mi mathvariant="italic">s</mml:mi>
										<mml:mi mathvariant="italic">G</mml:mi>
										</mml:msub>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Br</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <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">d</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">s</mml:mi>
										</mml:msub>
										<mml:mo>⁢</mml:mo>
										<mml:msub><mml:mi mathvariant="italic">s</mml:mi>
										<mml:mi mathvariant="italic">B</mml:mi>
										</mml:msub>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Ar</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <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">d</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">s</mml:mi>
										</mml:msub>
										<mml:mo>⁢</mml:mo>
										<mml:msub><mml:mi mathvariant="italic">s</mml:mi>
										<mml:mi mathvariant="italic">A</mml:mi>
										</mml:msub>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td></tr><tr><td align="left">
                        <code class="constant">GL_MIN</code>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Rr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">min</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Gr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">min</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Br</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">min</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Ar</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">min</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td></tr><tr><td align="left">
                        <code class="constant">GL_MAX</code>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Rr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">max</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Gr</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">max</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Br</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">max</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td><td align="left">
                            <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                                
                                <mml:mrow>
                                    <mml:mi mathvariant="italic">Ar</mml:mi>
                                    <mml:mo>=</mml:mo>
                                    <mml:mrow>
                                        <mml:mi mathvariant="italic">max</mml:mi>
                                        <mml:mo>⁡</mml:mo>
                                        <mml:mfenced open="(" close=")">
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                                <mml:mi mathvariant="italic">s</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                            <mml:mrow>
                                                <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
                                                <mml:mi mathvariant="italic">d</mml:mi>
                                                </mml:msub>
                                            </mml:mrow>
                                        </mml:mfenced>
                                    </mml:mrow>
                                </mml:mrow>
                            </mml:math></div>
                        </td></tr></tbody></table></div><p>
        </p><p>
            The results of these equations are clamped to the range 
                        <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                            
                            <mml:mfenced open="[" close="]">
                                <mml:mn>0</mml:mn>
                                <mml:mn>1</mml:mn>
                            </mml:mfenced>
                        </mml:math>.
        </p><p>
            The <code class="constant">GL_MIN</code> and <code class="constant">GL_MAX</code> equations are useful for applications
            that analyze image data (image thresholding against a constant color,
            for example).
            The <code class="constant">GL_FUNC_ADD</code> equation is useful
            for antialiasing and transparency, among other things.
        </p><p>
            Initially, both the RGB blend equation and the alpha blend equation are set to <code class="constant">GL_FUNC_ADD</code>.
        </p><p>
        </p></div><div class="refsect1"><a id="notes"></a><h2>Notes</h2><p>
            The <code class="constant">GL_MIN</code>, and <code class="constant">GL_MAX</code> equations do not use
            the source or destination factors, only the source and destination colors.
        </p></div><div class="refsect1"><a id="errors"></a><h2>Errors</h2><p>
            <code class="constant">GL_INVALID_ENUM</code> is generated if <em class="parameter"><code>mode</code></em> is not one of
            <code class="constant">GL_FUNC_ADD</code>, <code class="constant">GL_FUNC_SUBTRACT</code>, <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>,
            <code class="constant">GL_MAX</code>, or <code class="constant">GL_MIN</code>.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glBlendEquation</code> is executed
            between the execution of <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a> and the corresponding
            execution of <a class="citerefentry" href="glEnd.xml"><span class="citerefentry"><span class="refentrytitle">glEnd</span></span></a>.
        </p></div><div class="refsect1"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with an argument of <code class="constant">GL_BLEND_EQUATION_RGB</code>
         </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with an argument of <code class="constant">GL_BLEND_EQUATION_ALPHA</code>
         </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glGetString.xml"><span class="citerefentry"><span class="refentrytitle">glGetString</span></span></a>,
            <a class="citerefentry" href="glBlendColor.xml"><span class="citerefentry"><span class="refentrytitle">glBlendColor</span></span></a>,
            <a class="citerefentry" href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a>
            <a class="citerefentry" href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>
        </p></div><div class="refsect1"><a id="Copyright"></a><h2>Copyright</h2><p>
            Copyright <span class="trademark"></span>© 1991-2006
            Silicon Graphics, Inc. This document is licensed under the SGI
            Free Software B License. For details, see
            <a class="ulink" href="http://oss.sgi.com/projects/FreeB/" target="_top">http://oss.sgi.com/projects/FreeB/</a>.
        </p></div></div></body></html>