HCoop / clinton / guile-figl.git / blame
| Commit | Line | Data |
|---|---|---|
| 7faf1d71 AW |
1 | <?xml version="1.0" encoding="UTF-8"?>\r |
| 2 | <!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"\r | |
| 3 | "http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">\r | |
| 4 | <refentry id="glBlendEquationSeparate">\r | |
| 5 | <refmeta>\r | |
| 6 | <refmetainfo>\r | |
| 7 | <copyright>\r | |
| 8 | <year>1991-2006</year>\r | |
| 9 | <holder>Silicon Graphics, Inc.</holder>\r | |
| 10 | </copyright>\r | |
| 11 | </refmetainfo>\r | |
| 12 | <refentrytitle>glBlendEquationSeparate</refentrytitle>\r | |
| 13 | <manvolnum>3G</manvolnum>\r | |
| 14 | </refmeta>\r | |
| 15 | <refnamediv>\r | |
| 16 | <refname>glBlendEquationSeparate</refname>\r | |
| 17 | <refpurpose>set the RGB blend equation and the alpha blend equation separately</refpurpose>\r | |
| 18 | </refnamediv>\r | |
| 19 | <refsynopsisdiv><title>C Specification</title>\r | |
| 20 | <funcsynopsis>\r | |
| 21 | <funcprototype>\r | |
| 22 | <funcdef>void <function>glBlendEquationSeparate</function></funcdef>\r | |
| 23 | <paramdef>GLenum <parameter>modeRGB</parameter></paramdef>\r | |
| 24 | <paramdef>GLenum <parameter>modeAlpha</parameter></paramdef>\r | |
| 25 | </funcprototype>\r | |
| 26 | </funcsynopsis>\r | |
| 27 | </refsynopsisdiv>\r | |
| 28 | <!-- eqn: ignoring delim $$ -->\r | |
| 29 | <refsect1 id="parameters"><title>Parameters</title>\r | |
| 30 | <variablelist>\r | |
| 31 | <varlistentry>\r | |
| 32 | <term><parameter>modeRGB</parameter></term>\r | |
| 33 | <listitem>\r | |
| 34 | <para>\r | |
| 35 | specifies the RGB blend equation, how the red, green, and blue components of the source and destination colors are combined.\r | |
| 36 | It must be <constant>GL_FUNC_ADD</constant>, <constant>GL_FUNC_SUBTRACT</constant>,\r | |
| 37 | <constant>GL_FUNC_REVERSE_SUBTRACT</constant>, <constant>GL_MIN</constant>, <constant>GL_MAX</constant>.\r | |
| 38 | </para>\r | |
| 39 | </listitem>\r | |
| 40 | </varlistentry>\r | |
| 41 | <varlistentry>\r | |
| 42 | <term><parameter>modeAlpha</parameter></term>\r | |
| 43 | <listitem>\r | |
| 44 | <para>\r | |
| 45 | specifies the alpha blend equation, how the alpha component of the source and destination colors are combined.\r | |
| 46 | It must be <constant>GL_FUNC_ADD</constant>, <constant>GL_FUNC_SUBTRACT</constant>,\r | |
| 47 | <constant>GL_FUNC_REVERSE_SUBTRACT</constant>, <constant>GL_MIN</constant>, <constant>GL_MAX</constant>.\r | |
| 48 | </para>\r | |
| 49 | </listitem>\r | |
| 50 | </varlistentry>\r | |
| 51 | </variablelist>\r | |
| 52 | </refsect1>\r | |
| 53 | <refsect1 id="description"><title>Description</title>\r | |
| 54 | <para>\r | |
| 55 | The blend equations determines how a new pixel (the ''source'' color)\r | |
| 56 | is combined with a pixel already in the framebuffer (the ''destination''\r | |
| 57 | color). This function specifies one blend equation for the RGB-color \r | |
| 58 | components and one blend equation for the alpha component.\r | |
| 59 | </para>\r | |
| 60 | <para>\r | |
| 61 | The blend equations use the source and destination blend factors\r | |
| 62 | specified by either <citerefentry><refentrytitle>glBlendFunc</refentrytitle></citerefentry> or\r | |
| 63 | <citerefentry><refentrytitle>glBlendFuncSeparate</refentrytitle></citerefentry>.\r | |
| 64 | See <citerefentry><refentrytitle>glBlendFunc</refentrytitle></citerefentry> or <citerefentry><refentrytitle>glBlendFuncSeparate</refentrytitle></citerefentry>\r | |
| 65 | for a description of the various blend factors.\r | |
| 66 | </para>\r | |
| 67 | <para>\r | |
| 68 | In the equations that follow, source and destination\r | |
| 69 | color components are referred to as\r | |
| 70 | <inlineequation><mml:math>\r | |
| 71 | <!-- eqn: ( R sub s, G sub s, B sub s, A sub s ):-->\r | |
| 72 | <mml:mfenced open="(" close=")">\r | |
| 73 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 74 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 75 | </mml:msub>\r | |
| 76 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 77 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 78 | </mml:msub>\r | |
| 79 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 80 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 81 | </mml:msub>\r | |
| 82 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 83 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 84 | </mml:msub>\r | |
| 85 | </mml:mfenced>\r | |
| 86 | </mml:math></inlineequation>\r | |
| 87 | and\r | |
| 88 | <inlineequation><mml:math>\r | |
| 89 | <!-- eqn: ( R sub d, G sub d, B sub d, A sub d ):-->\r | |
| 90 | <mml:mfenced open="(" close=")">\r | |
| 91 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 92 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 93 | </mml:msub>\r | |
| 94 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 95 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 96 | </mml:msub>\r | |
| 97 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 98 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 99 | </mml:msub>\r | |
| 100 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 101 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 102 | </mml:msub>\r | |
| 103 | </mml:mfenced>\r | |
| 104 | </mml:math></inlineequation>,\r | |
| 105 | respectively.\r | |
| 106 | The result color is referred to as\r | |
| 107 | <inlineequation><mml:math>\r | |
| 108 | <!-- eqn: ( R sub r, G sub r, B sub r, A sub r ):-->\r | |
| 109 | <mml:mfenced open="(" close=")">\r | |
| 110 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 111 | <mml:mi mathvariant="italic">r</mml:mi>\r | |
| 112 | </mml:msub>\r | |
| 113 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 114 | <mml:mi mathvariant="italic">r</mml:mi>\r | |
| 115 | </mml:msub>\r | |
| 116 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 117 | <mml:mi mathvariant="italic">r</mml:mi>\r | |
| 118 | </mml:msub>\r | |
| 119 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 120 | <mml:mi mathvariant="italic">r</mml:mi>\r | |
| 121 | </mml:msub>\r | |
| 122 | </mml:mfenced>\r | |
| 123 | </mml:math></inlineequation>.\r | |
| 124 | The source and destination blend factors are denoted\r | |
| 125 | <inlineequation><mml:math>\r | |
| 126 | <!-- eqn: ( s sub R, s sub G, s sub B, s sub A ):-->\r | |
| 127 | <mml:mfenced open="(" close=")">\r | |
| 128 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 129 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 130 | </mml:msub>\r | |
| 131 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 132 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 133 | </mml:msub>\r | |
| 134 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 135 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 136 | </mml:msub>\r | |
| 137 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 138 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 139 | </mml:msub>\r | |
| 140 | </mml:mfenced>\r | |
| 141 | </mml:math></inlineequation>\r | |
| 142 | and\r | |
| 143 | <inlineequation><mml:math>\r | |
| 144 | <!-- eqn: ( d sub R, d sub G, d sub B, d sub A ):-->\r | |
| 145 | <mml:mfenced open="(" close=")">\r | |
| 146 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 147 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 148 | </mml:msub>\r | |
| 149 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 150 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 151 | </mml:msub>\r | |
| 152 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 153 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 154 | </mml:msub>\r | |
| 155 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 156 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 157 | </mml:msub>\r | |
| 158 | </mml:mfenced>\r | |
| 159 | </mml:math></inlineequation>,\r | |
| 160 | respectively.\r | |
| 161 | For these equations all color components are understood to have values\r | |
| 162 | in the range \r | |
| 163 | <inlineequation><mml:math>\r | |
| 164 | <!-- eqn: [0,1]:-->\r | |
| 165 | <mml:mfenced open="[" close="]">\r | |
| 166 | <mml:mn>0</mml:mn>\r | |
| 167 | <mml:mn>1</mml:mn>\r | |
| 168 | </mml:mfenced>\r | |
| 169 | </mml:math></inlineequation>.\r | |
| 170 | \r | |
| 171 | <informaltable frame="topbot">\r | |
| 172 | <tgroup cols="3" align="left">\r | |
| 173 | <colspec colwidth="1.1*" />\r | |
| 174 | <colspec colwidth="1*" />\r | |
| 175 | <colspec colwidth="1*" />\r | |
| 176 | <thead>\r | |
| 177 | <row>\r | |
| 178 | <entry rowsep="1" align="left"><emphasis role="bold">\r | |
| 179 | Mode\r | |
| 180 | </emphasis></entry>\r | |
| 181 | <entry rowsep="1" align="left"><emphasis role="bold">\r | |
| 182 | RGB Components\r | |
| 183 | </emphasis></entry>\r | |
| 184 | <entry rowsep="1" align="left"><emphasis role="bold">\r | |
| 185 | Alpha Component\r | |
| 186 | </emphasis></entry>\r | |
| 187 | </row>\r | |
| 188 | </thead>\r | |
| 189 | <tbody>\r | |
| 190 | <row>\r | |
| 191 | <entry align="left">\r | |
| 192 | <constant>GL_FUNC_ADD</constant>\r | |
| 193 | </entry>\r | |
| 194 | <entry align="left">\r | |
| 195 | <informalequation><mml:math>\r | |
| 196 | <!-- eqn: Rr = R sub s s sub R + R sub d d sub R :-->\r | |
| 197 | <mml:mrow>\r | |
| 198 | <mml:mi mathvariant="italic">Rr</mml:mi>\r | |
| 199 | <mml:mo>=</mml:mo>\r | |
| 200 | <mml:mrow>\r | |
| 201 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 202 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 203 | </mml:msub>\r | |
| 204 | <mml:mo>⁢</mml:mo>\r | |
| 205 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 206 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 207 | </mml:msub>\r | |
| 208 | <mml:mo>+</mml:mo>\r | |
| 209 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 210 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 211 | </mml:msub>\r | |
| 212 | <mml:mo>⁢</mml:mo>\r | |
| 213 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 214 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 215 | </mml:msub>\r | |
| 216 | </mml:mrow>\r | |
| 217 | </mml:mrow>\r | |
| 218 | </mml:math></informalequation>\r | |
| 219 | <informalequation><mml:math>\r | |
| 220 | <!-- eqn: Gr = G sub s s sub G + G sub d d sub G :-->\r | |
| 221 | <mml:mrow>\r | |
| 222 | <mml:mi mathvariant="italic">Gr</mml:mi>\r | |
| 223 | <mml:mo>=</mml:mo>\r | |
| 224 | <mml:mrow>\r | |
| 225 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 226 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 227 | </mml:msub>\r | |
| 228 | <mml:mo>⁢</mml:mo>\r | |
| 229 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 230 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 231 | </mml:msub>\r | |
| 232 | <mml:mo>+</mml:mo>\r | |
| 233 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 234 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 235 | </mml:msub>\r | |
| 236 | <mml:mo>⁢</mml:mo>\r | |
| 237 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 238 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 239 | </mml:msub>\r | |
| 240 | </mml:mrow>\r | |
| 241 | </mml:mrow>\r | |
| 242 | </mml:math></informalequation>\r | |
| 243 | <informalequation><mml:math>\r | |
| 244 | <!-- eqn: Br = B sub s s sub B + B sub d d sub B :-->\r | |
| 245 | <mml:mrow>\r | |
| 246 | <mml:mi mathvariant="italic">Br</mml:mi>\r | |
| 247 | <mml:mo>=</mml:mo>\r | |
| 248 | <mml:mrow>\r | |
| 249 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 250 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 251 | </mml:msub>\r | |
| 252 | <mml:mo>⁢</mml:mo>\r | |
| 253 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 254 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 255 | </mml:msub>\r | |
| 256 | <mml:mo>+</mml:mo>\r | |
| 257 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 258 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 259 | </mml:msub>\r | |
| 260 | <mml:mo>⁢</mml:mo>\r | |
| 261 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 262 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 263 | </mml:msub>\r | |
| 264 | </mml:mrow>\r | |
| 265 | </mml:mrow>\r | |
| 266 | </mml:math></informalequation>\r | |
| 267 | </entry>\r | |
| 268 | <entry align="left">\r | |
| 269 | <informalequation><mml:math>\r | |
| 270 | <!-- eqn: Ar = A sub s s sub A + A sub d d sub A :-->\r | |
| 271 | <mml:mrow>\r | |
| 272 | <mml:mi mathvariant="italic">Ar</mml:mi>\r | |
| 273 | <mml:mo>=</mml:mo>\r | |
| 274 | <mml:mrow>\r | |
| 275 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 276 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 277 | </mml:msub>\r | |
| 278 | <mml:mo>⁢</mml:mo>\r | |
| 279 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 280 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 281 | </mml:msub>\r | |
| 282 | <mml:mo>+</mml:mo>\r | |
| 283 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 284 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 285 | </mml:msub>\r | |
| 286 | <mml:mo>⁢</mml:mo>\r | |
| 287 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 288 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 289 | </mml:msub>\r | |
| 290 | </mml:mrow>\r | |
| 291 | </mml:mrow>\r | |
| 292 | </mml:math></informalequation>\r | |
| 293 | </entry>\r | |
| 294 | </row>\r | |
| 295 | <row>\r | |
| 296 | <entry align="left">\r | |
| 297 | <constant>GL_FUNC_SUBTRACT</constant>\r | |
| 298 | </entry>\r | |
| 299 | <entry align="left">\r | |
| 300 | <informalequation><mml:math>\r | |
| 301 | <!-- eqn: Rr = R sub s s sub R - R sub d d sub R :-->\r | |
| 302 | <mml:mrow>\r | |
| 303 | <mml:mi mathvariant="italic">Rr</mml:mi>\r | |
| 304 | <mml:mo>=</mml:mo>\r | |
| 305 | <mml:mrow>\r | |
| 306 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 307 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 308 | </mml:msub>\r | |
| 309 | <mml:mo>⁢</mml:mo>\r | |
| 310 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 311 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 312 | </mml:msub>\r | |
| 313 | <mml:mo>-</mml:mo>\r | |
| 314 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 315 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 316 | </mml:msub>\r | |
| 317 | <mml:mo>⁢</mml:mo>\r | |
| 318 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 319 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 320 | </mml:msub>\r | |
| 321 | </mml:mrow>\r | |
| 322 | </mml:mrow>\r | |
| 323 | </mml:math></informalequation>\r | |
| 324 | <informalequation><mml:math>\r | |
| 325 | <!-- eqn: Gr = G sub s s sub G - G sub d d sub G :-->\r | |
| 326 | <mml:mrow>\r | |
| 327 | <mml:mi mathvariant="italic">Gr</mml:mi>\r | |
| 328 | <mml:mo>=</mml:mo>\r | |
| 329 | <mml:mrow>\r | |
| 330 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 331 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 332 | </mml:msub>\r | |
| 333 | <mml:mo>⁢</mml:mo>\r | |
| 334 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 335 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 336 | </mml:msub>\r | |
| 337 | <mml:mo>-</mml:mo>\r | |
| 338 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 339 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 340 | </mml:msub>\r | |
| 341 | <mml:mo>⁢</mml:mo>\r | |
| 342 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 343 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 344 | </mml:msub>\r | |
| 345 | </mml:mrow>\r | |
| 346 | </mml:mrow>\r | |
| 347 | </mml:math></informalequation>\r | |
| 348 | <informalequation><mml:math>\r | |
| 349 | <!-- eqn: Br = B sub s s sub B - B sub d d sub B :-->\r | |
| 350 | <mml:mrow>\r | |
| 351 | <mml:mi mathvariant="italic">Br</mml:mi>\r | |
| 352 | <mml:mo>=</mml:mo>\r | |
| 353 | <mml:mrow>\r | |
| 354 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 355 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 356 | </mml:msub>\r | |
| 357 | <mml:mo>⁢</mml:mo>\r | |
| 358 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 359 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 360 | </mml:msub>\r | |
| 361 | <mml:mo>-</mml:mo>\r | |
| 362 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 363 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 364 | </mml:msub>\r | |
| 365 | <mml:mo>⁢</mml:mo>\r | |
| 366 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 367 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 368 | </mml:msub>\r | |
| 369 | </mml:mrow>\r | |
| 370 | </mml:mrow>\r | |
| 371 | </mml:math></informalequation>\r | |
| 372 | </entry>\r | |
| 373 | <entry align="left">\r | |
| 374 | <informalequation><mml:math>\r | |
| 375 | <!-- eqn: Ar = A sub s s sub A - A sub d d sub A :-->\r | |
| 376 | <mml:mrow>\r | |
| 377 | <mml:mi mathvariant="italic">Ar</mml:mi>\r | |
| 378 | <mml:mo>=</mml:mo>\r | |
| 379 | <mml:mrow>\r | |
| 380 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 381 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 382 | </mml:msub>\r | |
| 383 | <mml:mo>⁢</mml:mo>\r | |
| 384 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 385 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 386 | </mml:msub>\r | |
| 387 | <mml:mo>-</mml:mo>\r | |
| 388 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 389 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 390 | </mml:msub>\r | |
| 391 | <mml:mo>⁢</mml:mo>\r | |
| 392 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 393 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 394 | </mml:msub>\r | |
| 395 | </mml:mrow>\r | |
| 396 | </mml:mrow>\r | |
| 397 | </mml:math></informalequation>\r | |
| 398 | </entry>\r | |
| 399 | </row>\r | |
| 400 | <row>\r | |
| 401 | <entry align="left">\r | |
| 402 | <constant>GL_FUNC_REVERSE_SUBTRACT</constant>\r | |
| 403 | </entry>\r | |
| 404 | <entry align="left">\r | |
| 405 | <informalequation><mml:math>\r | |
| 406 | <!-- eqn: Rr = R sub d d sub R - R sub s s sub R :-->\r | |
| 407 | <mml:mrow>\r | |
| 408 | <mml:mi mathvariant="italic">Rr</mml:mi>\r | |
| 409 | <mml:mo>=</mml:mo>\r | |
| 410 | <mml:mrow>\r | |
| 411 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 412 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 413 | </mml:msub>\r | |
| 414 | <mml:mo>⁢</mml:mo>\r | |
| 415 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 416 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 417 | </mml:msub>\r | |
| 418 | <mml:mo>-</mml:mo>\r | |
| 419 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 420 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 421 | </mml:msub>\r | |
| 422 | <mml:mo>⁢</mml:mo>\r | |
| 423 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 424 | <mml:mi mathvariant="italic">R</mml:mi>\r | |
| 425 | </mml:msub>\r | |
| 426 | </mml:mrow>\r | |
| 427 | </mml:mrow>\r | |
| 428 | </mml:math></informalequation>\r | |
| 429 | <informalequation><mml:math>\r | |
| 430 | <!-- eqn: Gr = G sub d d sub G - G sub s s sub G :-->\r | |
| 431 | <mml:mrow>\r | |
| 432 | <mml:mi mathvariant="italic">Gr</mml:mi>\r | |
| 433 | <mml:mo>=</mml:mo>\r | |
| 434 | <mml:mrow>\r | |
| 435 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 436 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 437 | </mml:msub>\r | |
| 438 | <mml:mo>⁢</mml:mo>\r | |
| 439 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 440 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 441 | </mml:msub>\r | |
| 442 | <mml:mo>-</mml:mo>\r | |
| 443 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 444 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 445 | </mml:msub>\r | |
| 446 | <mml:mo>⁢</mml:mo>\r | |
| 447 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 448 | <mml:mi mathvariant="italic">G</mml:mi>\r | |
| 449 | </mml:msub>\r | |
| 450 | </mml:mrow>\r | |
| 451 | </mml:mrow>\r | |
| 452 | </mml:math></informalequation>\r | |
| 453 | <informalequation><mml:math>\r | |
| 454 | <!-- eqn: Br = B sub d d sub B - B sub s s sub B :-->\r | |
| 455 | <mml:mrow>\r | |
| 456 | <mml:mi mathvariant="italic">Br</mml:mi>\r | |
| 457 | <mml:mo>=</mml:mo>\r | |
| 458 | <mml:mrow>\r | |
| 459 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 460 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 461 | </mml:msub>\r | |
| 462 | <mml:mo>⁢</mml:mo>\r | |
| 463 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 464 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 465 | </mml:msub>\r | |
| 466 | <mml:mo>-</mml:mo>\r | |
| 467 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 468 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 469 | </mml:msub>\r | |
| 470 | <mml:mo>⁢</mml:mo>\r | |
| 471 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 472 | <mml:mi mathvariant="italic">B</mml:mi>\r | |
| 473 | </mml:msub>\r | |
| 474 | </mml:mrow>\r | |
| 475 | </mml:mrow>\r | |
| 476 | </mml:math></informalequation>\r | |
| 477 | </entry>\r | |
| 478 | <entry align="left">\r | |
| 479 | <informalequation><mml:math>\r | |
| 480 | <!-- eqn: Ar = A sub d d sub A - A sub s s sub A :-->\r | |
| 481 | <mml:mrow>\r | |
| 482 | <mml:mi mathvariant="italic">Ar</mml:mi>\r | |
| 483 | <mml:mo>=</mml:mo>\r | |
| 484 | <mml:mrow>\r | |
| 485 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 486 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 487 | </mml:msub>\r | |
| 488 | <mml:mo>⁢</mml:mo>\r | |
| 489 | <mml:msub><mml:mi mathvariant="italic">d</mml:mi>\r | |
| 490 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 491 | </mml:msub>\r | |
| 492 | <mml:mo>-</mml:mo>\r | |
| 493 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 494 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 495 | </mml:msub>\r | |
| 496 | <mml:mo>⁢</mml:mo>\r | |
| 497 | <mml:msub><mml:mi mathvariant="italic">s</mml:mi>\r | |
| 498 | <mml:mi mathvariant="italic">A</mml:mi>\r | |
| 499 | </mml:msub>\r | |
| 500 | </mml:mrow>\r | |
| 501 | </mml:mrow>\r | |
| 502 | </mml:math></informalequation>\r | |
| 503 | </entry>\r | |
| 504 | </row>\r | |
| 505 | <row>\r | |
| 506 | <entry align="left">\r | |
| 507 | <constant>GL_MIN</constant>\r | |
| 508 | </entry>\r | |
| 509 | <entry align="left">\r | |
| 510 | <informalequation><mml:math>\r | |
| 511 | <!-- eqn: Rr = min ( R sub s, R sub d):-->\r | |
| 512 | <mml:mrow>\r | |
| 513 | <mml:mi mathvariant="italic">Rr</mml:mi>\r | |
| 514 | <mml:mo>=</mml:mo>\r | |
| 515 | <mml:mrow>\r | |
| 516 | <mml:mi mathvariant="italic">min</mml:mi>\r | |
| 517 | <mml:mo>⁡</mml:mo>\r | |
| 518 | <mml:mfenced open="(" close=")">\r | |
| 519 | <mml:mrow>\r | |
| 520 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 521 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 522 | </mml:msub>\r | |
| 523 | </mml:mrow>\r | |
| 524 | <mml:mrow>\r | |
| 525 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 526 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 527 | </mml:msub>\r | |
| 528 | </mml:mrow>\r | |
| 529 | </mml:mfenced>\r | |
| 530 | </mml:mrow>\r | |
| 531 | </mml:mrow>\r | |
| 532 | </mml:math></informalequation>\r | |
| 533 | <informalequation><mml:math>\r | |
| 534 | <!-- eqn: Gr = min ( G sub s, G sub d):-->\r | |
| 535 | <mml:mrow>\r | |
| 536 | <mml:mi mathvariant="italic">Gr</mml:mi>\r | |
| 537 | <mml:mo>=</mml:mo>\r | |
| 538 | <mml:mrow>\r | |
| 539 | <mml:mi mathvariant="italic">min</mml:mi>\r | |
| 540 | <mml:mo>⁡</mml:mo>\r | |
| 541 | <mml:mfenced open="(" close=")">\r | |
| 542 | <mml:mrow>\r | |
| 543 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 544 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 545 | </mml:msub>\r | |
| 546 | </mml:mrow>\r | |
| 547 | <mml:mrow>\r | |
| 548 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 549 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 550 | </mml:msub>\r | |
| 551 | </mml:mrow>\r | |
| 552 | </mml:mfenced>\r | |
| 553 | </mml:mrow>\r | |
| 554 | </mml:mrow>\r | |
| 555 | </mml:math></informalequation>\r | |
| 556 | <informalequation><mml:math>\r | |
| 557 | <!-- eqn: Br = min ( B sub s, B sub d):-->\r | |
| 558 | <mml:mrow>\r | |
| 559 | <mml:mi mathvariant="italic">Br</mml:mi>\r | |
| 560 | <mml:mo>=</mml:mo>\r | |
| 561 | <mml:mrow>\r | |
| 562 | <mml:mi mathvariant="italic">min</mml:mi>\r | |
| 563 | <mml:mo>⁡</mml:mo>\r | |
| 564 | <mml:mfenced open="(" close=")">\r | |
| 565 | <mml:mrow>\r | |
| 566 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 567 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 568 | </mml:msub>\r | |
| 569 | </mml:mrow>\r | |
| 570 | <mml:mrow>\r | |
| 571 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 572 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 573 | </mml:msub>\r | |
| 574 | </mml:mrow>\r | |
| 575 | </mml:mfenced>\r | |
| 576 | </mml:mrow>\r | |
| 577 | </mml:mrow>\r | |
| 578 | </mml:math></informalequation>\r | |
| 579 | </entry>\r | |
| 580 | <entry align="left">\r | |
| 581 | <informalequation><mml:math>\r | |
| 582 | <!-- eqn: Ar = min ( A sub s, A sub d):-->\r | |
| 583 | <mml:mrow>\r | |
| 584 | <mml:mi mathvariant="italic">Ar</mml:mi>\r | |
| 585 | <mml:mo>=</mml:mo>\r | |
| 586 | <mml:mrow>\r | |
| 587 | <mml:mi mathvariant="italic">min</mml:mi>\r | |
| 588 | <mml:mo>⁡</mml:mo>\r | |
| 589 | <mml:mfenced open="(" close=")">\r | |
| 590 | <mml:mrow>\r | |
| 591 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 592 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 593 | </mml:msub>\r | |
| 594 | </mml:mrow>\r | |
| 595 | <mml:mrow>\r | |
| 596 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 597 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 598 | </mml:msub>\r | |
| 599 | </mml:mrow>\r | |
| 600 | </mml:mfenced>\r | |
| 601 | </mml:mrow>\r | |
| 602 | </mml:mrow>\r | |
| 603 | </mml:math></informalequation>\r | |
| 604 | </entry>\r | |
| 605 | </row>\r | |
| 606 | <row>\r | |
| 607 | <entry align="left">\r | |
| 608 | <constant>GL_MAX</constant>\r | |
| 609 | </entry>\r | |
| 610 | <entry align="left">\r | |
| 611 | <informalequation><mml:math>\r | |
| 612 | <!-- eqn: Rr = max ( R sub s, R sub d):-->\r | |
| 613 | <mml:mrow>\r | |
| 614 | <mml:mi mathvariant="italic">Rr</mml:mi>\r | |
| 615 | <mml:mo>=</mml:mo>\r | |
| 616 | <mml:mrow>\r | |
| 617 | <mml:mi mathvariant="italic">max</mml:mi>\r | |
| 618 | <mml:mo>⁡</mml:mo>\r | |
| 619 | <mml:mfenced open="(" close=")">\r | |
| 620 | <mml:mrow>\r | |
| 621 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 622 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 623 | </mml:msub>\r | |
| 624 | </mml:mrow>\r | |
| 625 | <mml:mrow>\r | |
| 626 | <mml:msub><mml:mi mathvariant="italic">R</mml:mi>\r | |
| 627 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 628 | </mml:msub>\r | |
| 629 | </mml:mrow>\r | |
| 630 | </mml:mfenced>\r | |
| 631 | </mml:mrow>\r | |
| 632 | </mml:mrow>\r | |
| 633 | </mml:math></informalequation>\r | |
| 634 | <informalequation><mml:math>\r | |
| 635 | <!-- eqn: Gr = max ( G sub s, G sub d):-->\r | |
| 636 | <mml:mrow>\r | |
| 637 | <mml:mi mathvariant="italic">Gr</mml:mi>\r | |
| 638 | <mml:mo>=</mml:mo>\r | |
| 639 | <mml:mrow>\r | |
| 640 | <mml:mi mathvariant="italic">max</mml:mi>\r | |
| 641 | <mml:mo>⁡</mml:mo>\r | |
| 642 | <mml:mfenced open="(" close=")">\r | |
| 643 | <mml:mrow>\r | |
| 644 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 645 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 646 | </mml:msub>\r | |
| 647 | </mml:mrow>\r | |
| 648 | <mml:mrow>\r | |
| 649 | <mml:msub><mml:mi mathvariant="italic">G</mml:mi>\r | |
| 650 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 651 | </mml:msub>\r | |
| 652 | </mml:mrow>\r | |
| 653 | </mml:mfenced>\r | |
| 654 | </mml:mrow>\r | |
| 655 | </mml:mrow>\r | |
| 656 | </mml:math></informalequation>\r | |
| 657 | <informalequation><mml:math>\r | |
| 658 | <!-- eqn: Br = max ( B sub s, B sub d):-->\r | |
| 659 | <mml:mrow>\r | |
| 660 | <mml:mi mathvariant="italic">Br</mml:mi>\r | |
| 661 | <mml:mo>=</mml:mo>\r | |
| 662 | <mml:mrow>\r | |
| 663 | <mml:mi mathvariant="italic">max</mml:mi>\r | |
| 664 | <mml:mo>⁡</mml:mo>\r | |
| 665 | <mml:mfenced open="(" close=")">\r | |
| 666 | <mml:mrow>\r | |
| 667 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 668 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 669 | </mml:msub>\r | |
| 670 | </mml:mrow>\r | |
| 671 | <mml:mrow>\r | |
| 672 | <mml:msub><mml:mi mathvariant="italic">B</mml:mi>\r | |
| 673 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 674 | </mml:msub>\r | |
| 675 | </mml:mrow>\r | |
| 676 | </mml:mfenced>\r | |
| 677 | </mml:mrow>\r | |
| 678 | </mml:mrow>\r | |
| 679 | </mml:math></informalequation>\r | |
| 680 | </entry>\r | |
| 681 | <entry align="left">\r | |
| 682 | <informalequation><mml:math>\r | |
| 683 | <!-- eqn: Ar = max ( A sub s, A sub d):-->\r | |
| 684 | <mml:mrow>\r | |
| 685 | <mml:mi mathvariant="italic">Ar</mml:mi>\r | |
| 686 | <mml:mo>=</mml:mo>\r | |
| 687 | <mml:mrow>\r | |
| 688 | <mml:mi mathvariant="italic">max</mml:mi>\r | |
| 689 | <mml:mo>⁡</mml:mo>\r | |
| 690 | <mml:mfenced open="(" close=")">\r | |
| 691 | <mml:mrow>\r | |
| 692 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 693 | <mml:mi mathvariant="italic">s</mml:mi>\r | |
| 694 | </mml:msub>\r | |
| 695 | </mml:mrow>\r | |
| 696 | <mml:mrow>\r | |
| 697 | <mml:msub><mml:mi mathvariant="italic">A</mml:mi>\r | |
| 698 | <mml:mi mathvariant="italic">d</mml:mi>\r | |
| 699 | </mml:msub>\r | |
| 700 | </mml:mrow>\r | |
| 701 | </mml:mfenced>\r | |
| 702 | </mml:mrow>\r | |
| 703 | </mml:mrow>\r | |
| 704 | </mml:math></informalequation>\r | |
| 705 | </entry>\r | |
| 706 | </row>\r | |
| 707 | </tbody>\r | |
| 708 | </tgroup>\r | |
| 709 | </informaltable>\r | |
| 710 | </para>\r | |
| 711 | <para>\r | |
| 712 | The results of these equations are clamped to the range \r | |
| 713 | <inlineequation><mml:math>\r | |
| 714 | <!-- eqn: [0,1]:-->\r | |
| 715 | <mml:mfenced open="[" close="]">\r | |
| 716 | <mml:mn>0</mml:mn>\r | |
| 717 | <mml:mn>1</mml:mn>\r | |
| 718 | </mml:mfenced>\r | |
| 719 | </mml:math></inlineequation>.\r | |
| 720 | </para>\r | |
| 721 | <para>\r | |
| 722 | The <constant>GL_MIN</constant> and <constant>GL_MAX</constant> equations are useful for applications\r | |
| 723 | that analyze image data (image thresholding against a constant color,\r | |
| 724 | for example).\r | |
| 725 | The <constant>GL_FUNC_ADD</constant> equation is useful\r | |
| 726 | for antialiasing and transparency, among other things.\r | |
| 727 | </para>\r | |
| 728 | <para>\r | |
| 729 | Initially, both the RGB blend equation and the alpha blend equation are set to <constant>GL_FUNC_ADD</constant>.\r | |
| 730 | </para>\r | |
| 731 | <para>\r | |
| 732 | </para>\r | |
| 733 | </refsect1>\r | |
| 734 | <refsect1 id="notes"><title>Notes</title>\r | |
| 735 | <para>\r | |
| 736 | The <constant>GL_MIN</constant>, and <constant>GL_MAX</constant> equations do not use\r | |
| 737 | the source or destination factors, only the source and destination colors.\r | |
| 738 | </para>\r | |
| 739 | </refsect1>\r | |
| 740 | <refsect1 id="errors"><title>Errors</title>\r | |
| 741 | <para>\r | |
| 742 | <constant>GL_INVALID_ENUM</constant> is generated if either <parameter>modeRGB</parameter> or <parameter>modeAlpha</parameter> is not one of\r | |
| 743 | <constant>GL_FUNC_ADD</constant>, <constant>GL_FUNC_SUBTRACT</constant>, <constant>GL_FUNC_REVERSE_SUBTRACT</constant>,\r | |
| 744 | <constant>GL_MAX</constant>, or <constant>GL_MIN</constant>.\r | |
| 745 | </para>\r | |
| 746 | </refsect1>\r | |
| 747 | <refsect1 id="associatedgets"><title>Associated Gets</title>\r | |
| 748 | <para>\r | |
| 749 | <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with an argument of <constant>GL_BLEND_EQUATION_RGB</constant>\r | |
| 750 | </para>\r | |
| 751 | <para>\r | |
| 752 | <citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with an argument of <constant>GL_BLEND_EQUATION_ALPHA</constant>\r | |
| 753 | </para>\r | |
| 754 | </refsect1>\r | |
| 755 | <refsect1 id="seealso"><title>See Also</title>\r | |
| 756 | <para>\r | |
| 757 | <citerefentry><refentrytitle>glGetString</refentrytitle></citerefentry>,\r | |
| 758 | <citerefentry><refentrytitle>glBlendColor</refentrytitle></citerefentry>,\r | |
| 759 | <citerefentry><refentrytitle>glBlendFunc</refentrytitle></citerefentry>,\r | |
| 760 | <citerefentry><refentrytitle>glBlendFuncSeparate</refentrytitle></citerefentry>\r | |
| 761 | </para>\r | |
| 762 | </refsect1>\r | |
| 763 | <refsect1 id="Copyright"><title>Copyright</title>\r | |
| 764 | <para>\r | |
| 765 | Copyright <trademark class="copyright"></trademark> 2006 Khronos Group. \r | |
| 766 | This material may be distributed subject to the terms and conditions set forth in \r | |
| 767 | the Open Publication License, v 1.0, 8 June 1999.\r | |
| 768 | <ulink url="http://opencontent.org/openpub/">http://opencontent.org/openpub/</ulink>.\r | |
| 769 | </para>\r | |
| 770 | </refsect1>\r | |
| 771 | </refentry>\r |