upstream-man-pages/man3/glDrawRangeElements.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
   3               "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
   4 <refentry id="glDrawRangeElements">
   5     <refmeta>
   6         <refmetainfo>
   7             <copyright>
   8                 <year>1991-2006</year>
   9                 <holder>Silicon Graphics, Inc.</holder>
  10             </copyright>
  11         </refmetainfo>
  12         <refentrytitle>glDrawRangeElements</refentrytitle>
  13         <manvolnum>3G</manvolnum>
  14     </refmeta>
  15     <refnamediv>
  16         <refname>glDrawRangeElements</refname>
  17         <refpurpose>render primitives from array data</refpurpose>
  18     </refnamediv>
  19     <refsynopsisdiv><title>C Specification</title>
  20         <funcsynopsis>
  21             <funcprototype>
  22                 <funcdef>void <function>glDrawRangeElements</function></funcdef>
  23                 <paramdef>GLenum <parameter>mode</parameter></paramdef>
  24                 <paramdef>GLuint <parameter>start</parameter></paramdef>
  25                 <paramdef>GLuint <parameter>end</parameter></paramdef>
  26                 <paramdef>GLsizei <parameter>count</parameter></paramdef>
  27                 <paramdef>GLenum <parameter>type</parameter></paramdef>
  28                 <paramdef>const GLvoid * <parameter>indices</parameter></paramdef>
  29             </funcprototype>
  30         </funcsynopsis>
  31     </refsynopsisdiv>
  32     <!-- eqn: ignoring delim $$ -->
  33     <refsect1 id="parameters"><title>Parameters</title>
  34         <variablelist>
  35         <varlistentry>
  36             <term><parameter>mode</parameter></term>
  37             <listitem>
  38                 <para>
  39                     Specifies what kind of primitives to render.
  40                     Symbolic constants
  41                     <constant>GL_POINTS</constant>,
  42                     <constant>GL_LINE_STRIP</constant>,
  43                     <constant>GL_LINE_LOOP</constant>,
  44                     <constant>GL_LINES</constant>,
  45                     <constant>GL_LINE_STRIP_ADJACENCY</constant>,
  46                     <constant>GL_LINES_ADJACENCY</constant>,
  47                     <constant>GL_TRIANGLE_STRIP</constant>,
  48                     <constant>GL_TRIANGLE_FAN</constant>,
  49                     <constant>GL_TRIANGLES</constant>,
  50                     <constant>GL_TRIANGLE_STRIP_ADJACENCY</constant> and
  51                     <constant>GL_TRIANGLES_ADJACENCY</constant>
  52                     are accepted.
  53                 </para>
  54             </listitem>
  55         </varlistentry>
  56         <varlistentry>
  57             <term><parameter>start</parameter></term>
  58             <listitem>
  59                 <para>
  60                     Specifies the minimum array index contained in <parameter>indices</parameter>.
  61                 </para>
  62             </listitem>
  63         </varlistentry>
  64         <varlistentry>
  65             <term><parameter>end</parameter></term>
  66             <listitem>
  67                 <para>
  68                     Specifies the maximum array index contained in <parameter>indices</parameter>.
  69                 </para>
  70             </listitem>
  71         </varlistentry>
  72         <varlistentry>
  73             <term><parameter>count</parameter></term>
  74             <listitem>
  75                 <para>
  76                     Specifies the number of elements to be rendered.
  77                 </para>
  78             </listitem>
  79         </varlistentry>
  80         <varlistentry>
  81             <term><parameter>type</parameter></term>
  82             <listitem>
  83                 <para>
  84                     Specifies the type of the values in <parameter>indices</parameter>. Must be one of
  85                     <constant>GL_UNSIGNED_BYTE</constant>, <constant>GL_UNSIGNED_SHORT</constant>, or
  86                     <constant>GL_UNSIGNED_INT</constant>.
  87                 </para>
  88             </listitem>
  89         </varlistentry>
  90         <varlistentry>
  91             <term><parameter>indices</parameter></term>
  92             <listitem>
  93                 <para>
  94                     Specifies a pointer to the location where the indices are stored.
  95                 </para>
  96             </listitem>
  97         </varlistentry>
  98         </variablelist>
  99     </refsect1>
 100     <refsect1 id="description"><title>Description</title>
 101         <para>
 102             <function>glDrawRangeElements</function> is a restricted form of <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>. <parameter>mode</parameter>, <parameter>start</parameter>, <parameter>end</parameter>,
 103             and <parameter>count</parameter> match the corresponding arguments to <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>, with
 104             the additional constraint that all values in the arrays <parameter>count</parameter> must lie
 105             between <parameter>start</parameter> and <parameter>end</parameter>, inclusive.
 106         </para>
 107         <para>
 108             Implementations denote recommended maximum amounts of vertex and
 109             index data,
 110             which may be queried by calling <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument
 111             <constant>GL_MAX_ELEMENTS_VERTICES</constant> and <constant>GL_MAX_ELEMENTS_INDICES</constant>.
 112             If
 113             <inlineequation><mml:math>
 114                 <!-- eqn: end  -  start  +  1: -->
 115                 <mml:mrow>
 116                     <mml:mi mathvariant="italic">end</mml:mi>
 117                     <mml:mo>-</mml:mo>
 118                     <mml:mi mathvariant="italic">start</mml:mi>
 119                     <mml:mo>+</mml:mo>
 120                     <mml:mn>1</mml:mn>
 121                 </mml:mrow>
 122             </mml:math></inlineequation>
 123             is greater than the value of
 124             <constant>GL_MAX_ELEMENTS_VERTICES</constant>, or if <parameter>count</parameter> is greater than the value of
 125             <constant>GL_MAX_ELEMENTS_INDICES</constant>, then the call may operate at reduced
 126             performance.  There is no requirement that all vertices in the range
 127             <inlineequation><mml:math>
 128                 <!-- eqn: [start, end]: -->
 129                 <mml:mfenced open="[" close="]">
 130                     <mml:mi mathvariant="italic">start</mml:mi>
 131                     <mml:mi mathvariant="italic">end</mml:mi>
 132                 </mml:mfenced>
 133             </mml:math></inlineequation>
 134             be referenced.  However, the implementation may
 135             partially process unused vertices, reducing performance from what could
 136             be achieved with an optimal index set.
 137         </para>
 138         <para>
 139             When <function>glDrawRangeElements</function> is called, it uses <parameter>count</parameter> sequential elements from an
 140             enabled array, starting at <parameter>start</parameter> to construct a sequence of
 141             geometric primitives. <parameter>mode</parameter> specifies what kind of primitives are
 142             constructed, and how the array elements construct these primitives. If
 143             more than one array is enabled, each is used.
 144         </para>
 145         <para>
 146             Vertex attributes that are modified by <function>glDrawRangeElements</function> have an
 147             unspecified value after <function>glDrawRangeElements</function> returns. Attributes that aren't
 148             modified maintain their previous values.
 149         </para>
 150     </refsect1>
 151     <refsect1 id="notes"><title>Notes</title>
 152         <para>
 153             <constant>GL_LINE_STRIP_ADJACENCY</constant>,
 154             <constant>GL_LINES_ADJACENCY</constant>,
 155             <constant>GL_TRIANGLE_STRIP_ADJACENCY</constant> and
 156             <constant>GL_TRIANGLES_ADJACENCY</constant>
 157             are available only if the GL version is 3.2 or greater.
 158         </para>
 159     </refsect1>
 160     <refsect1 id="errors"><title>Errors</title>
 161         <para>
 162             It is an error for indices to lie outside the range
 163             <inlineequation><mml:math>
 164                 <!-- eqn: [start, end]: -->
 165                 <mml:mfenced open="[" close="]">
 166                     <mml:mi mathvariant="italic">start</mml:mi>
 167                     <mml:mi mathvariant="italic">end</mml:mi>
 168                 </mml:mfenced>
 169             </mml:math></inlineequation>,
 170             but implementations may not check for this situation. Such indices
 171             cause implementation-dependent behavior.
 172         </para>
 173         <para>
 174             <constant>GL_INVALID_ENUM</constant> is generated if <parameter>mode</parameter> is not an accepted value.
 175         </para>
 176         <para>
 177             <constant>GL_INVALID_VALUE</constant> is generated if <parameter>count</parameter> is negative.
 178         </para>
 179         <para>
 180             <constant>GL_INVALID_VALUE</constant> is generated if
 181             <inlineequation><mml:math>
 182                 <!-- eqn: end < start: -->
 183                 <mml:mrow>
 184                     <mml:mi mathvariant="italic">end</mml:mi>
 185                     <mml:mo>&lt;</mml:mo>
 186                     <mml:mi mathvariant="italic">start</mml:mi>
 187                 </mml:mrow>
 188             </mml:math></inlineequation>.
 189         </para>
 190         <para>
 191             <constant>GL_INVALID_OPERATION</constant> is generated if a geometry shader is active and <parameter>mode</parameter>
 192             is incompatible with the input primitive type of the geometry shader in the currently installed program object.
 193         </para>
 194         <para>
 195             <constant>GL_INVALID_OPERATION</constant> is generated if a non-zero buffer object name is bound to an
 196             enabled array or the element array and the buffer object's data store is currently mapped.
 197         </para>
 198     </refsect1>
 199     <refsect1 id="associatedgets"><title>Associated Gets</title>
 200         <para>
 201             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_ELEMENTS_VERTICES</constant>
 202         </para>
 203         <para>
 204             <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_MAX_ELEMENTS_INDICES</constant>
 205         </para>
 206     </refsect1>
 207     <refsect1 id="seealso"><title>See Also</title>
 208         <para>
 209             <citerefentry><refentrytitle>glDrawArrays</refentrytitle></citerefentry>,
 210             <citerefentry><refentrytitle>glDrawElements</refentrytitle></citerefentry>,
 211             <citerefentry><refentrytitle>glDrawElementsBaseVertex</refentrytitle></citerefentry>
 212         </para>
 213     </refsect1>
 214     <refsect1 id="Copyright"><title>Copyright</title>
 215         <para>
 216             Copyright <trademark class="copyright"></trademark> 1991-2006
 217             Silicon Graphics, Inc. This document is licensed under the SGI
 218             Free Software B License. For details, see
 219             <ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
 220         </para>
 221     </refsect1>
 222 </refentry>