upstream-man-pages/man4/xhtml/glBlendEquationSeparate.xml

   1 <?xml version="1.0" encoding="UTF-8"?>
   2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "xhtml1-transitional.dtd">
   3 <!-- saved from url=(0013)about:internet -->
   4 <?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" /><link rel="stylesheet" type="text/css" href="opengl-man.css" /><title>glBlendEquationSeparate - OpenGL 4 Reference Pages</title><meta name="generator" content="DocBook XSL Stylesheets V1.69.1" /></head><body><div class="refentry" lang="en" xml:lang="en"><a id="glBlendEquationSeparate"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>glBlendEquationSeparate — set the RGB blend equation and the alpha blend equation separately</p></div><div class="refsynopsisdiv"><h2>C Specification</h2><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">glBlendEquationSeparate</b>(</code></td><td>GLenum  </td><td><var class="pdparam">modeRGB</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">modeAlpha</var><code>)</code>;</td></tr></table><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0"><tr><td><code class="funcdef">void <b class="fsfunc">glBlendEquationSeparatei</b>(</code></td><td>GLuint  </td><td><var class="pdparam">buf</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">modeRGB</var>, </td></tr><tr><td> </td><td>GLenum  </td><td><var class="pdparam">modeAlpha</var><code>)</code>;</td></tr></table></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="parameters"></a><h2>Parameters</h2><div class="variablelist"><dl><dt><span class="term"><em class="parameter"><code>buf</code></em></span></dt><dd><p>
   5                     for <code class="function">glBlendEquationSeparatei</code>, specifies the index of the draw buffer for which
   6                     to set the blend equations.
   7                 </p></dd><dt><span class="term"><em class="parameter"><code>modeRGB</code></em></span></dt><dd><p>
   8                     specifies the RGB blend equation, how the red, green, and blue components of the source and destination colors are combined.
   9                     It must be <code class="constant">GL_FUNC_ADD</code>, <code class="constant">GL_FUNC_SUBTRACT</code>,
  10                     <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>, <code class="constant">GL_MIN</code>, <code class="constant">GL_MAX</code>.
  11                 </p></dd><dt><span class="term"><em class="parameter"><code>modeAlpha</code></em></span></dt><dd><p>
  12                     specifies the alpha blend equation, how the alpha component of the source and destination colors are combined.
  13                     It must be <code class="constant">GL_FUNC_ADD</code>, <code class="constant">GL_FUNC_SUBTRACT</code>,
  14                     <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>, <code class="constant">GL_MIN</code>, <code class="constant">GL_MAX</code>.
  15                 </p></dd></dl></div></div><div class="refsect1" lang="en" xml:lang="en"><a id="description"></a><h2>Description</h2><p>
  16             The blend equations determines how a new pixel (the ''source'' color)
  17             is combined with a pixel already in the framebuffer (the ''destination''
  18             color).  These functions specifie one blend equation for the RGB-color
  19             components and one blend equation for the alpha component. <code class="function">glBlendEquationSeparatei</code>
  20             specifies the blend equations for a single draw buffer whereas <code class="function">glBlendEquationSeparate</code>
  21             sets the blend equations for all draw buffers.
  22         </p><p>
  23             The blend equations use the source and destination blend factors
  24             specified by either <a href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a> or
  25             <a href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>.
  26             See <a href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a> or <a href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>
  27             for a description of the various blend factors.
  28         </p><p>
  29             In the equations that follow, source and destination
  30             color components are referred to as
  31             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  32
  33                 <mml:mfenced open="(" close=")">
  34                     <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
  35                     <mml:mi mathvariant="italic">s</mml:mi>
  36                     </mml:msub>
  37                     <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
  38                     <mml:mi mathvariant="italic">s</mml:mi>
  39                     </mml:msub>
  40                     <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
  41                     <mml:mi mathvariant="italic">s</mml:mi>
  42                     </mml:msub>
  43                     <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
  44                     <mml:mi mathvariant="italic">s</mml:mi>
  45                     </mml:msub>
  46                 </mml:mfenced>
  47             </mml:math>
  48             and
  49             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  50
  51                 <mml:mfenced open="(" close=")">
  52                     <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
  53                     <mml:mi mathvariant="italic">d</mml:mi>
  54                     </mml:msub>
  55                     <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
  56                     <mml:mi mathvariant="italic">d</mml:mi>
  57                     </mml:msub>
  58                     <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
  59                     <mml:mi mathvariant="italic">d</mml:mi>
  60                     </mml:msub>
  61                     <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
  62                     <mml:mi mathvariant="italic">d</mml:mi>
  63                     </mml:msub>
  64                 </mml:mfenced>
  65             </mml:math>,
  66             respectively.
  67             The result color is referred to as
  68             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  69
  70                 <mml:mfenced open="(" close=")">
  71                     <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
  72                     <mml:mi mathvariant="italic">r</mml:mi>
  73                     </mml:msub>
  74                     <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
  75                     <mml:mi mathvariant="italic">r</mml:mi>
  76                     </mml:msub>
  77                     <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
  78                     <mml:mi mathvariant="italic">r</mml:mi>
  79                     </mml:msub>
  80                     <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
  81                     <mml:mi mathvariant="italic">r</mml:mi>
  82                     </mml:msub>
  83                 </mml:mfenced>
  84             </mml:math>.
  85             The source and destination blend factors are denoted
  86             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
  87
  88                 <mml:mfenced open="(" close=")">
  89                     <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
  90                     <mml:mi mathvariant="italic">R</mml:mi>
  91                     </mml:msub>
  92                     <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
  93                     <mml:mi mathvariant="italic">G</mml:mi>
  94                     </mml:msub>
  95                     <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
  96                     <mml:mi mathvariant="italic">B</mml:mi>
  97                     </mml:msub>
  98                     <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
  99                     <mml:mi mathvariant="italic">A</mml:mi>
 100                     </mml:msub>
 101                 </mml:mfenced>
 102             </mml:math>
 103             and
 104             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 105
 106                 <mml:mfenced open="(" close=")">
 107                     <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 108                     <mml:mi mathvariant="italic">R</mml:mi>
 109                     </mml:msub>
 110                     <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 111                     <mml:mi mathvariant="italic">G</mml:mi>
 112                     </mml:msub>
 113                     <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 114                     <mml:mi mathvariant="italic">B</mml:mi>
 115                     </mml:msub>
 116                     <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 117                     <mml:mi mathvariant="italic">A</mml:mi>
 118                     </mml:msub>
 119                 </mml:mfenced>
 120             </mml:math>,
 121             respectively.
 122             For these equations all color components are understood to have values
 123             in the range
 124             <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 125
 126                 <mml:mfenced open="[" close="]">
 127                     <mml:mn>0</mml:mn>
 128                     <mml:mn>1</mml:mn>
 129                 </mml:mfenced>
 130             </mml:math>.
 131
 132         </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>
 133                         Mode
 134                         </strong></span></th><th align="left"><span class="bold"><strong>
 135                         RGB Components
 136                         </strong></span></th><th align="left"><span class="bold"><strong>
 137                         Alpha Component
 138                         </strong></span></th></tr></thead><tbody><tr><td align="left">
 139                         <code class="constant">GL_FUNC_ADD</code>
 140                         </td><td align="left">
 141                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 142
 143                             <mml:mrow>
 144                                 <mml:mi mathvariant="italic">Rr</mml:mi>
 145                                 <mml:mo>=</mml:mo>
 146                                 <mml:mrow>
 147                                                                         <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 148                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 149                                                                         </mml:msub>
 150                                                                         <mml:mo>⁢</mml:mo>
 151                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 152                                                                         <mml:mi mathvariant="italic">R</mml:mi>
 153                                                                         </mml:msub>
 154                                                                         <mml:mo>+</mml:mo>
 155                                                                         <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 156                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 157                                                                         </mml:msub>
 158                                                                         <mml:mo>⁢</mml:mo>
 159                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 160                                                                         <mml:mi mathvariant="italic">R</mml:mi>
 161                                                                         </mml:msub>
 162                                 </mml:mrow>
 163                             </mml:mrow>
 164                         </mml:math></div>
 165                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 166
 167                             <mml:mrow>
 168                                 <mml:mi mathvariant="italic">Gr</mml:mi>
 169                                 <mml:mo>=</mml:mo>
 170                                 <mml:mrow>
 171                                                                         <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 172                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 173                                                                         </mml:msub>
 174                                                                         <mml:mo>⁢</mml:mo>
 175                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 176                                                                         <mml:mi mathvariant="italic">G</mml:mi>
 177                                                                         </mml:msub>
 178                                                                         <mml:mo>+</mml:mo>
 179                                                                         <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 180                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 181                                                                         </mml:msub>
 182                                                                         <mml:mo>⁢</mml:mo>
 183                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 184                                                                         <mml:mi mathvariant="italic">G</mml:mi>
 185                                                                         </mml:msub>
 186                                 </mml:mrow>
 187                             </mml:mrow>
 188                         </mml:math></div>
 189                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 190
 191                             <mml:mrow>
 192                                 <mml:mi mathvariant="italic">Br</mml:mi>
 193                                 <mml:mo>=</mml:mo>
 194                                 <mml:mrow>
 195                                                                         <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 196                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 197                                                                         </mml:msub>
 198                                                                         <mml:mo>⁢</mml:mo>
 199                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 200                                                                         <mml:mi mathvariant="italic">B</mml:mi>
 201                                                                         </mml:msub>
 202                                                                         <mml:mo>+</mml:mo>
 203                                                                         <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 204                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 205                                                                         </mml:msub>
 206                                                                         <mml:mo>⁢</mml:mo>
 207                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 208                                                                         <mml:mi mathvariant="italic">B</mml:mi>
 209                                                                         </mml:msub>
 210                                 </mml:mrow>
 211                             </mml:mrow>
 212                         </mml:math></div>
 213                         </td><td align="left">
 214                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 215
 216                             <mml:mrow>
 217                                 <mml:mi mathvariant="italic">Ar</mml:mi>
 218                                 <mml:mo>=</mml:mo>
 219                                 <mml:mrow>
 220                                                                         <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 221                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 222                                                                         </mml:msub>
 223                                                                         <mml:mo>⁢</mml:mo>
 224                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 225                                                                         <mml:mi mathvariant="italic">A</mml:mi>
 226                                                                         </mml:msub>
 227                                                                         <mml:mo>+</mml:mo>
 228                                                                         <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 229                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 230                                                                         </mml:msub>
 231                                                                         <mml:mo>⁢</mml:mo>
 232                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 233                                                                         <mml:mi mathvariant="italic">A</mml:mi>
 234                                                                         </mml:msub>
 235                                 </mml:mrow>
 236                             </mml:mrow>
 237                         </mml:math></div>
 238                         </td></tr><tr><td align="left">
 239                         <code class="constant">GL_FUNC_SUBTRACT</code>
 240                         </td><td align="left">
 241                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 242
 243                             <mml:mrow>
 244                                 <mml:mi mathvariant="italic">Rr</mml:mi>
 245                                 <mml:mo>=</mml:mo>
 246                                 <mml:mrow>
 247                                                                         <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 248                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 249                                                                         </mml:msub>
 250                                                                         <mml:mo>⁢</mml:mo>
 251                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 252                                                                         <mml:mi mathvariant="italic">R</mml:mi>
 253                                                                         </mml:msub>
 254                                                                         <mml:mo>-</mml:mo>
 255                                                                         <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 256                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 257                                                                         </mml:msub>
 258                                                                         <mml:mo>⁢</mml:mo>
 259                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 260                                                                         <mml:mi mathvariant="italic">R</mml:mi>
 261                                                                         </mml:msub>
 262                                 </mml:mrow>
 263                             </mml:mrow>
 264                         </mml:math></div>
 265                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 266
 267                             <mml:mrow>
 268                                 <mml:mi mathvariant="italic">Gr</mml:mi>
 269                                 <mml:mo>=</mml:mo>
 270                                 <mml:mrow>
 271                                                                         <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 272                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 273                                                                         </mml:msub>
 274                                                                         <mml:mo>⁢</mml:mo>
 275                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 276                                                                         <mml:mi mathvariant="italic">G</mml:mi>
 277                                                                         </mml:msub>
 278                                                                         <mml:mo>-</mml:mo>
 279                                                                         <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 280                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 281                                                                         </mml:msub>
 282                                                                         <mml:mo>⁢</mml:mo>
 283                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 284                                                                         <mml:mi mathvariant="italic">G</mml:mi>
 285                                                                         </mml:msub>
 286                                 </mml:mrow>
 287                             </mml:mrow>
 288                         </mml:math></div>
 289                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 290
 291                             <mml:mrow>
 292                                 <mml:mi mathvariant="italic">Br</mml:mi>
 293                                 <mml:mo>=</mml:mo>
 294                                 <mml:mrow>
 295                                                                         <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 296                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 297                                                                         </mml:msub>
 298                                                                         <mml:mo>⁢</mml:mo>
 299                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 300                                                                         <mml:mi mathvariant="italic">B</mml:mi>
 301                                                                         </mml:msub>
 302                                                                         <mml:mo>-</mml:mo>
 303                                                                         <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 304                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 305                                                                         </mml:msub>
 306                                                                         <mml:mo>⁢</mml:mo>
 307                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 308                                                                         <mml:mi mathvariant="italic">B</mml:mi>
 309                                                                         </mml:msub>
 310                                 </mml:mrow>
 311                             </mml:mrow>
 312                         </mml:math></div>
 313                         </td><td align="left">
 314                         <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 315
 316                             <mml:mrow>
 317                                 <mml:mi mathvariant="italic">Ar</mml:mi>
 318                                 <mml:mo>=</mml:mo>
 319                                 <mml:mrow>
 320                                                                         <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 321                                                                         <mml:mi mathvariant="italic">s</mml:mi>
 322                                                                         </mml:msub>
 323                                                                         <mml:mo>⁢</mml:mo>
 324                                                                         <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 325                                                                         <mml:mi mathvariant="italic">A</mml:mi>
 326                                                                         </mml:msub>
 327                                                                         <mml:mo>-</mml:mo>
 328                                                                         <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 329                                                                         <mml:mi mathvariant="italic">d</mml:mi>
 330                                                                         </mml:msub>
 331                                                                         <mml:mo>⁢</mml:mo>
 332                                                                         <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 333                                                                         <mml:mi mathvariant="italic">A</mml:mi>
 334                                                                         </mml:msub>
 335                                 </mml:mrow>
 336                             </mml:mrow>
 337                         </mml:math></div>
 338                         </td></tr><tr><td align="left">
 339                         <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>
 340                         </td><td align="left">
 341                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 342
 343                                 <mml:mrow>
 344                                     <mml:mi mathvariant="italic">Rr</mml:mi>
 345                                     <mml:mo>=</mml:mo>
 346                                     <mml:mrow>
 347                                                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 348                                                                                 <mml:mi mathvariant="italic">d</mml:mi>
 349                                                                                 </mml:msub>
 350                                                                                 <mml:mo>⁢</mml:mo>
 351                                                                                 <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 352                                                                                 <mml:mi mathvariant="italic">R</mml:mi>
 353                                                                                 </mml:msub>
 354                                                                                 <mml:mo>-</mml:mo>
 355                                                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 356                                                                                 <mml:mi mathvariant="italic">s</mml:mi>
 357                                                                                 </mml:msub>
 358                                                                                 <mml:mo>⁢</mml:mo>
 359                                                                                 <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 360                                                                                 <mml:mi mathvariant="italic">R</mml:mi>
 361                                                                                 </mml:msub>
 362                                     </mml:mrow>
 363                                 </mml:mrow>
 364                             </mml:math></div>
 365                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 366
 367                                 <mml:mrow>
 368                                     <mml:mi mathvariant="italic">Gr</mml:mi>
 369                                     <mml:mo>=</mml:mo>
 370                                     <mml:mrow>
 371                                                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 372                                                                                 <mml:mi mathvariant="italic">d</mml:mi>
 373                                                                                 </mml:msub>
 374                                                                                 <mml:mo>⁢</mml:mo>
 375                                                                                 <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 376                                                                                 <mml:mi mathvariant="italic">G</mml:mi>
 377                                                                                 </mml:msub>
 378                                                                                 <mml:mo>-</mml:mo>
 379                                                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 380                                                                                 <mml:mi mathvariant="italic">s</mml:mi>
 381                                                                                 </mml:msub>
 382                                                                                 <mml:mo>⁢</mml:mo>
 383                                                                                 <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 384                                                                                 <mml:mi mathvariant="italic">G</mml:mi>
 385                                                                                 </mml:msub>
 386                                     </mml:mrow>
 387                                 </mml:mrow>
 388                             </mml:math></div>
 389                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 390
 391                                 <mml:mrow>
 392                                     <mml:mi mathvariant="italic">Br</mml:mi>
 393                                     <mml:mo>=</mml:mo>
 394                                     <mml:mrow>
 395                                                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 396                                                                                 <mml:mi mathvariant="italic">d</mml:mi>
 397                                                                                 </mml:msub>
 398                                                                                 <mml:mo>⁢</mml:mo>
 399                                                                                 <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 400                                                                                 <mml:mi mathvariant="italic">B</mml:mi>
 401                                                                                 </mml:msub>
 402                                                                                 <mml:mo>-</mml:mo>
 403                                                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 404                                                                                 <mml:mi mathvariant="italic">s</mml:mi>
 405                                                                                 </mml:msub>
 406                                                                                 <mml:mo>⁢</mml:mo>
 407                                                                                 <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 408                                                                                 <mml:mi mathvariant="italic">B</mml:mi>
 409                                                                                 </mml:msub>
 410                                     </mml:mrow>
 411                                 </mml:mrow>
 412                             </mml:math></div>
 413                         </td><td align="left">
 414                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 415
 416                                 <mml:mrow>
 417                                     <mml:mi mathvariant="italic">Ar</mml:mi>
 418                                     <mml:mo>=</mml:mo>
 419                                     <mml:mrow>
 420                                                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 421                                                                                 <mml:mi mathvariant="italic">d</mml:mi>
 422                                                                                 </mml:msub>
 423                                                                                 <mml:mo>⁢</mml:mo>
 424                                                                                 <mml:msub><mml:mi mathvariant="italic">d</mml:mi>
 425                                                                                 <mml:mi mathvariant="italic">A</mml:mi>
 426                                                                                 </mml:msub>
 427                                                                                 <mml:mo>-</mml:mo>
 428                                                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 429                                                                                 <mml:mi mathvariant="italic">s</mml:mi>
 430                                                                                 </mml:msub>
 431                                                                                 <mml:mo>⁢</mml:mo>
 432                                                                                 <mml:msub><mml:mi mathvariant="italic">s</mml:mi>
 433                                                                                 <mml:mi mathvariant="italic">A</mml:mi>
 434                                                                                 </mml:msub>
 435                                     </mml:mrow>
 436                                 </mml:mrow>
 437                             </mml:math></div>
 438                         </td></tr><tr><td align="left">
 439                         <code class="constant">GL_MIN</code>
 440                         </td><td align="left">
 441                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 442
 443                                 <mml:mrow>
 444                                     <mml:mi mathvariant="italic">Rr</mml:mi>
 445                                     <mml:mo>=</mml:mo>
 446                                     <mml:mrow>
 447                                         <mml:mi mathvariant="italic">min</mml:mi>
 448                                         <mml:mo>⁡</mml:mo>
 449                                         <mml:mfenced open="(" close=")">
 450                                             <mml:mrow>
 451                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 452                                                 <mml:mi mathvariant="italic">s</mml:mi>
 453                                                 </mml:msub>
 454                                             </mml:mrow>
 455                                             <mml:mrow>
 456                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 457                                                 <mml:mi mathvariant="italic">d</mml:mi>
 458                                                 </mml:msub>
 459                                             </mml:mrow>
 460                                         </mml:mfenced>
 461                                     </mml:mrow>
 462                                 </mml:mrow>
 463                             </mml:math></div>
 464                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 465
 466                                 <mml:mrow>
 467                                     <mml:mi mathvariant="italic">Gr</mml:mi>
 468                                     <mml:mo>=</mml:mo>
 469                                     <mml:mrow>
 470                                         <mml:mi mathvariant="italic">min</mml:mi>
 471                                         <mml:mo>⁡</mml:mo>
 472                                         <mml:mfenced open="(" close=")">
 473                                             <mml:mrow>
 474                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 475                                                 <mml:mi mathvariant="italic">s</mml:mi>
 476                                                 </mml:msub>
 477                                             </mml:mrow>
 478                                             <mml:mrow>
 479                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 480                                                 <mml:mi mathvariant="italic">d</mml:mi>
 481                                                 </mml:msub>
 482                                             </mml:mrow>
 483                                         </mml:mfenced>
 484                                     </mml:mrow>
 485                                 </mml:mrow>
 486                             </mml:math></div>
 487                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 488
 489                                 <mml:mrow>
 490                                     <mml:mi mathvariant="italic">Br</mml:mi>
 491                                     <mml:mo>=</mml:mo>
 492                                     <mml:mrow>
 493                                         <mml:mi mathvariant="italic">min</mml:mi>
 494                                         <mml:mo>⁡</mml:mo>
 495                                         <mml:mfenced open="(" close=")">
 496                                             <mml:mrow>
 497                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 498                                                 <mml:mi mathvariant="italic">s</mml:mi>
 499                                                 </mml:msub>
 500                                             </mml:mrow>
 501                                             <mml:mrow>
 502                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 503                                                 <mml:mi mathvariant="italic">d</mml:mi>
 504                                                 </mml:msub>
 505                                             </mml:mrow>
 506                                         </mml:mfenced>
 507                                     </mml:mrow>
 508                                 </mml:mrow>
 509                             </mml:math></div>
 510                         </td><td align="left">
 511                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 512
 513                                 <mml:mrow>
 514                                     <mml:mi mathvariant="italic">Ar</mml:mi>
 515                                     <mml:mo>=</mml:mo>
 516                                     <mml:mrow>
 517                                         <mml:mi mathvariant="italic">min</mml:mi>
 518                                         <mml:mo>⁡</mml:mo>
 519                                         <mml:mfenced open="(" close=")">
 520                                             <mml:mrow>
 521                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 522                                                 <mml:mi mathvariant="italic">s</mml:mi>
 523                                                 </mml:msub>
 524                                             </mml:mrow>
 525                                             <mml:mrow>
 526                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 527                                                 <mml:mi mathvariant="italic">d</mml:mi>
 528                                                 </mml:msub>
 529                                             </mml:mrow>
 530                                         </mml:mfenced>
 531                                     </mml:mrow>
 532                                 </mml:mrow>
 533                             </mml:math></div>
 534                         </td></tr><tr><td align="left">
 535                         <code class="constant">GL_MAX</code>
 536                         </td><td align="left">
 537                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 538
 539                                 <mml:mrow>
 540                                     <mml:mi mathvariant="italic">Rr</mml:mi>
 541                                     <mml:mo>=</mml:mo>
 542                                     <mml:mrow>
 543                                         <mml:mi mathvariant="italic">max</mml:mi>
 544                                         <mml:mo>⁡</mml:mo>
 545                                         <mml:mfenced open="(" close=")">
 546                                             <mml:mrow>
 547                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 548                                                 <mml:mi mathvariant="italic">s</mml:mi>
 549                                                 </mml:msub>
 550                                             </mml:mrow>
 551                                             <mml:mrow>
 552                                                 <mml:msub><mml:mi mathvariant="italic">R</mml:mi>
 553                                                 <mml:mi mathvariant="italic">d</mml:mi>
 554                                                 </mml:msub>
 555                                             </mml:mrow>
 556                                         </mml:mfenced>
 557                                     </mml:mrow>
 558                                 </mml:mrow>
 559                             </mml:math></div>
 560                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 561
 562                                 <mml:mrow>
 563                                     <mml:mi mathvariant="italic">Gr</mml:mi>
 564                                     <mml:mo>=</mml:mo>
 565                                     <mml:mrow>
 566                                         <mml:mi mathvariant="italic">max</mml:mi>
 567                                         <mml:mo>⁡</mml:mo>
 568                                         <mml:mfenced open="(" close=")">
 569                                             <mml:mrow>
 570                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 571                                                 <mml:mi mathvariant="italic">s</mml:mi>
 572                                                 </mml:msub>
 573                                             </mml:mrow>
 574                                             <mml:mrow>
 575                                                 <mml:msub><mml:mi mathvariant="italic">G</mml:mi>
 576                                                 <mml:mi mathvariant="italic">d</mml:mi>
 577                                                 </mml:msub>
 578                                             </mml:mrow>
 579                                         </mml:mfenced>
 580                                     </mml:mrow>
 581                                 </mml:mrow>
 582                             </mml:math></div>
 583                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 584
 585                                 <mml:mrow>
 586                                     <mml:mi mathvariant="italic">Br</mml:mi>
 587                                     <mml:mo>=</mml:mo>
 588                                     <mml:mrow>
 589                                         <mml:mi mathvariant="italic">max</mml:mi>
 590                                         <mml:mo>⁡</mml:mo>
 591                                         <mml:mfenced open="(" close=")">
 592                                             <mml:mrow>
 593                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 594                                                 <mml:mi mathvariant="italic">s</mml:mi>
 595                                                 </mml:msub>
 596                                             </mml:mrow>
 597                                             <mml:mrow>
 598                                                 <mml:msub><mml:mi mathvariant="italic">B</mml:mi>
 599                                                 <mml:mi mathvariant="italic">d</mml:mi>
 600                                                 </mml:msub>
 601                                             </mml:mrow>
 602                                         </mml:mfenced>
 603                                     </mml:mrow>
 604                                 </mml:mrow>
 605                             </mml:math></div>
 606                         </td><td align="left">
 607                             <div class="informalequation"><mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 608
 609                                 <mml:mrow>
 610                                     <mml:mi mathvariant="italic">Ar</mml:mi>
 611                                     <mml:mo>=</mml:mo>
 612                                     <mml:mrow>
 613                                         <mml:mi mathvariant="italic">max</mml:mi>
 614                                         <mml:mo>⁡</mml:mo>
 615                                         <mml:mfenced open="(" close=")">
 616                                             <mml:mrow>
 617                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 618                                                 <mml:mi mathvariant="italic">s</mml:mi>
 619                                                 </mml:msub>
 620                                             </mml:mrow>
 621                                             <mml:mrow>
 622                                                 <mml:msub><mml:mi mathvariant="italic">A</mml:mi>
 623                                                 <mml:mi mathvariant="italic">d</mml:mi>
 624                                                 </mml:msub>
 625                                             </mml:mrow>
 626                                         </mml:mfenced>
 627                                     </mml:mrow>
 628                                 </mml:mrow>
 629                             </mml:math></div>
 630                         </td></tr></tbody></table></div><p>
 631         </p><p>
 632             The results of these equations are clamped to the range
 633                         <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll">
 634
 635                             <mml:mfenced open="[" close="]">
 636                                 <mml:mn>0</mml:mn>
 637                                 <mml:mn>1</mml:mn>
 638                             </mml:mfenced>
 639                         </mml:math>.
 640         </p><p>
 641             The <code class="constant">GL_MIN</code> and <code class="constant">GL_MAX</code> equations are useful for applications
 642             that analyze image data (image thresholding against a constant color,
 643             for example).
 644             The <code class="constant">GL_FUNC_ADD</code> equation is useful
 645             for antialiasing and transparency, among other things.
 646         </p><p>
 647             Initially, both the RGB blend equation and the alpha blend equation are set to <code class="constant">GL_FUNC_ADD</code>.
 648         </p><p>
 649         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="notes"></a><h2>Notes</h2><p>
 650             The <code class="constant">GL_MIN</code>, and <code class="constant">GL_MAX</code> equations do not use
 651             the source or destination factors, only the source and destination colors.
 652         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="errors"></a><h2>Errors</h2><p>
 653             <code class="constant">GL_INVALID_ENUM</code> is generated if either <em class="parameter"><code>modeRGB</code></em> or <em class="parameter"><code>modeAlpha</code></em> is not one of
 654             <code class="constant">GL_FUNC_ADD</code>, <code class="constant">GL_FUNC_SUBTRACT</code>, <code class="constant">GL_FUNC_REVERSE_SUBTRACT</code>,
 655             <code class="constant">GL_MAX</code>, or <code class="constant">GL_MIN</code>.
 656         </p><p>
 657             <code class="constant">GL_INVALID_VALUE</code> is generated by <code class="function">glBlendEquationSeparatei</code> if <em class="parameter"><code>buf</code></em> is greater
 658             than or equal to the value of <code class="constant">GL_MAX_DRAW_BUFFERS</code>.
 659         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="associatedgets"></a><h2>Associated Gets</h2><p>
 660                     <a 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>
 661                 </p><p>
 662                     <a 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>
 663                 </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="seealso"></a><h2>See Also</h2><p>
 664             <a href="glGetString.xml"><span class="citerefentry"><span class="refentrytitle">glGetString</span></span></a>,
 665             <a href="glBlendColor.xml"><span class="citerefentry"><span class="refentrytitle">glBlendColor</span></span></a>,
 666             <a href="glBlendFunc.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFunc</span></span></a>,
 667             <a href="glBlendFuncSeparate.xml"><span class="citerefentry"><span class="refentrytitle">glBlendFuncSeparate</span></span></a>
 668         </p></div><div class="refsect1" lang="en" xml:lang="en"><a id="Copyright"></a><h2>Copyright</h2><p>
 669             Copyright <span class="trademark"></span>© 2006 Khronos Group.
 670             This material may be distributed subject to the terms and conditions set forth in
 671             the Open Publication License, v 1.0, 8 June 1999.
 672             <a href="http://opencontent.org/openpub/" target="_top">http://opencontent.org/openpub/</a>.
 673         </p></div></div></body></html>