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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>glEvalMesh</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1" /></head><body><div class="refentry"><a id="glEvalMesh"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glEvalMesh — compute a one- or two-dimensional grid of points or lines</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">glEvalMesh1</strong>(</code></td><td>GLenum <var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">i1</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">i2</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>
                    In <code class="function">glEvalMesh1</code>, specifies whether to compute a one-dimensional mesh of points or lines.
                    Symbolic constants
                    <code class="constant">GL_POINT</code> and
                    <code class="constant">GL_LINE</code> are accepted.
                </p></dd><dt><span class="term"><em class="parameter"><code>i1</code></em>, </span><span class="term"><em class="parameter"><code>i2</code></em></span></dt><dd><p>
                    Specify the first and last integer values for grid domain variable 
                    <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">i</mml:mi></mml:math>.
                </p></dd></dl></div></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">glEvalMesh2</strong>(</code></td><td>GLenum <var class="pdparam">mode</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">i1</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">i2</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">j1</var>, </td></tr><tr><td> </td><td>GLint <var class="pdparam">j2</var><code>)</code>;</td></tr></table><div class="funcprototype-spacer"> </div></div></div><div class="refsect1"><a id="parameters2"></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>
                    In <code class="function">glEvalMesh2</code>, specifies whether to compute a two-dimensional mesh of points, lines,
                    or polygons.
                    Symbolic constants
                    <code class="constant">GL_POINT</code>,
                    <code class="constant">GL_LINE</code>, and
                    <code class="constant">GL_FILL</code> are accepted.
                </p></dd><dt><span class="term"><em class="parameter"><code>i1</code></em>, </span><span class="term"><em class="parameter"><code>i2</code></em></span></dt><dd><p>
                    Specify the first and last integer values for grid domain variable 
                    <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">i</mml:mi></mml:math>.
                </p></dd><dt><span class="term"><em class="parameter"><code>j1</code></em>, </span><span class="term"><em class="parameter"><code>j2</code></em></span></dt><dd><p>
                    Specify the first and last integer values for grid domain variable 
                    <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">j</mml:mi></mml:math>.
                </p></dd></dl></div></div><div class="refsect1"><a id="description"></a><h2>Description</h2><p>
            <a class="citerefentry" href="glMapGrid.xml"><span class="citerefentry"><span class="refentrytitle">glMapGrid</span></span></a> and <code class="function">glEvalMesh</code> are used in tandem to efficiently
            generate and evaluate a series of evenly-spaced map domain values.
            <code class="function">glEvalMesh</code> steps through the integer domain of a one- or two-dimensional grid,
            whose range is the domain of the evaluation maps specified by
            <a class="citerefentry" href="glMap1.xml"><span class="citerefentry"><span class="refentrytitle">glMap1</span></span></a> and <a class="citerefentry" href="glMap2.xml"><span class="citerefentry"><span class="refentrytitle">glMap2</span></span></a>.
            <em class="parameter"><code>mode</code></em> determines whether the resulting vertices are connected as
            points,
            lines,
            or filled polygons.
        </p><p>
            In the one-dimensional case,
            <code class="function">glEvalMesh1</code>,
            the mesh is generated as if the following code fragment were executed:
        </p><p>
            </p><pre class="programlisting">
glBegin( <em class="parameter"><code>type</code></em> );
for ( i = <em class="parameter"><code>i1</code></em>; i &lt;= <em class="parameter"><code>i2</code></em>; i += 1 )
   glEvalCoord1( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
   		      
		      <mml:mrow>
		          <mml:mrow>
		              <mml:mn>i</mml:mn>
			      <mml:mo>·</mml:mo>
			      <mml:mo>Δ</mml:mo>
		              <mml:mi mathvariant="italic">u</mml:mi>
		          </mml:mrow>
		          <mml:mo>+</mml:mo>
		          <mml:msub>
		              <mml:mi mathvariant="italic">u</mml:mi>
		              <mml:mn>1</mml:mn>
		          </mml:msub>
		      </mml:mrow>
		  </mml:math> );
glEnd();
            </pre><p>
            where
        </p><p>
            </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mo>Δ</mml:mo>
                        <mml:mi mathvariant="italic">u</mml:mi>
                    </mml:mrow>
                    <mml:mo>=</mml:mo>
                    <mml:mfrac>
                        <mml:mfenced open="(" close=")">
                            <mml:mrow>
                                <mml:msub>
				    <mml:mi mathvariant="italic">u</mml:mi>
                                    <mml:mn>2</mml:mn>
                                </mml:msub>
                                <mml:mo>-</mml:mo>
                                <mml:msub>
				    <mml:mi mathvariant="italic">u</mml:mi>
                                    <mml:mn>1</mml:mn>
                                </mml:msub>
                            </mml:mrow>
                        </mml:mfenced>
                        <mml:mi mathvariant="italic">n</mml:mi>
                    </mml:mfrac>
                </mml:mrow>
            </mml:math></div><p>
        </p><p>
            and 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">n</mml:mi></mml:math>, 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>1</mml:mn>
                </mml:msub>
            </mml:math>,
            and 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>
            are the arguments to the most recent
            <a class="citerefentry" href="glMapGrid1.xml"><span class="citerefentry"><span class="refentrytitle">glMapGrid1</span></span></a> command.
            <span class="emphasis"><em>type</em></span> is <code class="constant">GL_POINTS</code> if <em class="parameter"><code>mode</code></em> is <code class="constant">GL_POINT</code>,
            or <code class="constant">GL_LINES</code> if <em class="parameter"><code>mode</code></em> is <code class="constant">GL_LINE</code>.
        </p><p>
            The one absolute numeric requirement is that if 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mi mathvariant="italic">i</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mi mathvariant="italic">n</mml:mi>
                </mml:mrow>
            </mml:math>,
            then the
            value computed from 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mi mathvariant="italic">i</mml:mi>
                        <mml:mo>·</mml:mo>
                        <mml:mrow>
                            <mml:mo>Δ</mml:mo>
                            <mml:mi mathvariant="italic">u</mml:mi>
                        </mml:mrow>
                    </mml:mrow>
                    <mml:mo>+</mml:mo>
                    <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                    <mml:mn>1</mml:mn>
                    </mml:msub>
                </mml:mrow>
            </mml:math>
            is exactly 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>.
        </p><p>
            In the two-dimensional case, <code class="function">glEvalMesh2</code>, let
            .cp
            </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mo>Δ</mml:mo>
                        <mml:mi mathvariant="italic">u</mml:mi>
                    </mml:mrow>
                    <mml:mo>=</mml:mo>
                    <mml:mfrac>
                        <mml:mfenced open="(" close=")">
                            <mml:mrow>
                                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                                <mml:mn>2</mml:mn>
                                </mml:msub>
                                <mml:mo>-</mml:mo>
                                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                                <mml:mn>1</mml:mn>
                                </mml:msub>
                            </mml:mrow>
                        </mml:mfenced>
                        <mml:mi mathvariant="italic">n</mml:mi>
                    </mml:mfrac>
                </mml:mrow>
            </mml:math></div><p>
        </p><p>
            </p><div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mo>Δ</mml:mo>
                        <mml:mi mathvariant="italic">v</mml:mi>
                    </mml:mrow>
                    <mml:mo>=</mml:mo>
                    <mml:mfrac>
                        <mml:mfenced open="(" close=")">
                            <mml:mrow>
                                <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                                <mml:mn>2</mml:mn>
                                </mml:msub>
                                <mml:mo>-</mml:mo>
                                <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                                <mml:mn>1</mml:mn>
                                </mml:msub>
                            </mml:mrow>
                        </mml:mfenced>
                        <mml:mi mathvariant="italic">m</mml:mi>
                    </mml:mfrac>
                </mml:mrow>
            </mml:math></div><p>
        </p><p>
            where 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">n</mml:mi></mml:math>, 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>1</mml:mn>
                </mml:msub>
            </mml:math>, 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>, 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"><mml:mi mathvariant="italic">m</mml:mi></mml:math>, 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                <mml:mn>1</mml:mn>
                </mml:msub>
            </mml:math>,
            and 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>
            are the
            arguments to the most recent <a class="citerefentry" href="glMapGrid2.xml"><span class="citerefentry"><span class="refentrytitle">glMapGrid2</span></span></a> command.  Then, if
            <em class="parameter"><code>mode</code></em> is <code class="constant">GL_FILL</code>, the <code class="function">glEvalMesh2</code> command is equivalent
            to:
        </p><p>
            </p><pre class="programlisting">
for ( j = <em class="parameter"><code>j1</code></em>; j &lt; <em class="parameter"><code>j2</code></em>; j += 1 ) {
   glBegin( GL_QUAD_STRIP );
   for ( i = <em class="parameter"><code>i1</code></em>; i &lt;= <em class="parameter"><code>i2</code></em>; i += 1 ) {
      glEvalCoord2( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
			
		        <mml:mrow>
			    <mml:mrow>
			        <mml:mn>i</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">u</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">u</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			    <mml:mo>,</mml:mo>
			    
			    <mml:mrow>
			        <mml:mn>j</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">v</mml:mi>

			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">v</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			</mml:mrow>
		    </mml:math> );
      glEvalCoord2( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
			
		        <mml:mrow>
			    <mml:mrow>
			        <mml:mn>i</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">u</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">u</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			    <mml:mo>,</mml:mo>
			    
			    <mml:mrow>
			        <mml:mrow>
				    <mml:mfenced open="(" close=")">
				        <mml:mrow>
			                    <mml:mn>j</mml:mn>
				            <mml:mo>+</mml:mo>
			                    <mml:mn>1</mml:mn>
				        </mml:mrow>
				    </mml:mfenced>
				</mml:mrow>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">v</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">v</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			</mml:mrow>
		    </mml:math> );
   }
   glEnd();
}
            </pre><p>
        </p><p>
            If <em class="parameter"><code>mode</code></em> is <code class="constant">GL_LINE</code>, then a call to <code class="function">glEvalMesh2</code> is equivalent to:
        </p><p>
            </p><pre class="programlisting">
for ( j = <em class="parameter"><code>j1</code></em>; j &lt;= <em class="parameter"><code>j2</code></em>; j += 1 ) {
   glBegin( GL_LINE_STRIP );
   for ( i = <em class="parameter"><code>i1</code></em>; i &lt;= <em class="parameter"><code>i2</code></em>; i += 1 )
      glEvalCoord2( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
			
		        <mml:mrow>
			    <mml:mrow>
			        <mml:mn>i</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">u</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">u</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			    <mml:mo>,</mml:mo>
			    
			    <mml:mrow>
			        <mml:mn>j</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">v</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">v</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			</mml:mrow>
		    </mml:math> );
   glEnd();
}

for ( i = <em class="parameter"><code>i1</code></em>;  i &lt;= <em class="parameter"><code>i2</code></em>; i += 1 ) {
   glBegin( GL_LINE_STRIP );
   for ( j = <em class="parameter"><code>j1</code></em>; j &lt;= <em class="parameter"><code>j1</code></em>; j += 1 )
      glEvalCoord2( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
			
		        <mml:mrow>
			    <mml:mrow>
			        <mml:mn>i</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">u</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">u</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			    <mml:mo>,</mml:mo>
			    
			    <mml:mrow>
			        <mml:mn>j</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">v</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">v</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			</mml:mrow>
		    </mml:math> );
   glEnd();
}
            </pre><p>
        </p><p>
            And finally, if <em class="parameter"><code>mode</code></em> is <code class="constant">GL_POINT</code>, then a call to
            <code class="function">glEvalMesh2</code> is equivalent to:
        </p><p>
            </p><pre class="programlisting">
glBegin( GL_POINTS );
for ( j = <em class="parameter"><code>j1</code></em>; j &lt;= <em class="parameter"><code>j2</code></em>; j += 1 )
   for ( i = <em class="parameter"><code>i1</code></em>; i &lt;= <em class="parameter"><code>i2</code></em>; i += 1 )
      glEvalCoord2( <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
			
		        <mml:mrow>
			    <mml:mrow>
			        <mml:mn>i</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">u</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">u</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			    <mml:mo>,</mml:mo>
			    
			    <mml:mrow>
			        <mml:mn>j</mml:mn>
				<mml:mo>·</mml:mo>
			        <mml:mo>Δ</mml:mo>
		                <mml:mi mathvariant="italic">v</mml:mi>
			    </mml:mrow>
		            <mml:mo>+</mml:mo>
		            <mml:msub>
		                <mml:mi mathvariant="italic">v</mml:mi>
		                <mml:mn>1</mml:mn>
		            </mml:msub>
			</mml:mrow>
		    </mml:math> );
glEnd();
            </pre><p>
        </p><p>
            In all three cases, the only absolute numeric requirements are that if 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mi mathvariant="italic">i</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mi mathvariant="italic">n</mml:mi>
                </mml:mrow>
            </mml:math>,
            then the value computed from 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mi mathvariant="italic">i</mml:mi>
                        <mml:mo>·</mml:mo>
                        <mml:mrow>
                            <mml:mo>Δ</mml:mo>
                            <mml:mi mathvariant="italic">u</mml:mi>
                        </mml:mrow>
                    </mml:mrow>
                    <mml:mo>+</mml:mo>
                    <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                    <mml:mn>1</mml:mn>
                    </mml:msub>
                </mml:mrow>
            </mml:math>
            is exactly
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">u</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>,
            and if 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mi mathvariant="italic">j</mml:mi>
                    <mml:mo>=</mml:mo>
                    <mml:mi mathvariant="italic">m</mml:mi>
                </mml:mrow>
            </mml:math>,
            then the value computed from
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:mrow>
                    <mml:mrow>
                        <mml:mi mathvariant="italic">j</mml:mi>
                        <mml:mo>·</mml:mo>
                        <mml:mrow>
                            <mml:mo>Δ</mml:mo>
                            <mml:mi mathvariant="italic">v</mml:mi>
                        </mml:mrow>
                    </mml:mrow>
                    <mml:mo>+</mml:mo>
                    <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                    <mml:mn>1</mml:mn>
                    </mml:msub>
                </mml:mrow>
            </mml:math>
            is exactly 
            <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
                
                <mml:msub><mml:mi mathvariant="italic">v</mml:mi>
                <mml:mn>2</mml:mn>
                </mml:msub>
            </mml:math>.
        </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 an accepted value.
        </p><p>
            <code class="constant">GL_INVALID_OPERATION</code> is generated if <code class="function">glEvalMesh</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 argument <code class="constant">GL_MAP1_GRID_DOMAIN</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAP2_GRID_DOMAIN</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAP1_GRID_SEGMENTS</code>
        </p><p>
            <a class="citerefentry" href="glGet.xml"><span class="citerefentry"><span class="refentrytitle">glGet</span></span></a> with argument <code class="constant">GL_MAP2_GRID_SEGMENTS</code>
        </p></div><div class="refsect1"><a id="seealso"></a><h2>See Also</h2><p>
            <a class="citerefentry" href="glBegin.xml"><span class="citerefentry"><span class="refentrytitle">glBegin</span></span></a>,
            <a class="citerefentry" href="glEvalCoord.xml"><span class="citerefentry"><span class="refentrytitle">glEvalCoord</span></span></a>,
            <a class="citerefentry" href="glEvalPoint.xml"><span class="citerefentry"><span class="refentrytitle">glEvalPoint</span></span></a>,
            <a class="citerefentry" href="glMap1.xml"><span class="citerefentry"><span class="refentrytitle">glMap1</span></span></a>,
            <a class="citerefentry" href="glMap2.xml"><span class="citerefentry"><span class="refentrytitle">glMap2</span></span></a>,
            <a class="citerefentry" href="glMapGrid.xml"><span class="citerefentry"><span class="refentrytitle">glMapGrid</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>