mirror of
https://github.com/Ryujinx/Opentk.git
synced 2024-12-26 20:05:37 +00:00
430 lines
22 KiB
XML
430 lines
22 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
|
|
<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
|
|
"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
|
|
<refentry id="gluBuild2DMipmaps">
|
|
<refmeta>
|
|
<refmetainfo>
|
|
<copyright>
|
|
<year>1991-2006</year>
|
|
<holder>Silicon Graphics, Inc.</holder>
|
|
</copyright>
|
|
</refmetainfo>
|
|
<refentrytitle>gluBuild2DMipmaps</refentrytitle>
|
|
<manvolnum>3G</manvolnum>
|
|
</refmeta>
|
|
<refnamediv>
|
|
<refname>gluBuild2DMipmaps</refname>
|
|
<refpurpose>builds a two-dimensional mipmap</refpurpose>
|
|
</refnamediv>
|
|
<refsynopsisdiv><title>C Specification</title>
|
|
<funcsynopsis>
|
|
<funcprototype>
|
|
<funcdef>GLint <function>gluBuild2DMipmaps</function></funcdef>
|
|
<paramdef>GLenum <parameter>target</parameter></paramdef>
|
|
<paramdef>GLint <parameter>internalFormat</parameter></paramdef>
|
|
<paramdef>GLsizei <parameter>width</parameter></paramdef>
|
|
<paramdef>GLsizei <parameter>height</parameter></paramdef>
|
|
<paramdef>GLenum <parameter>format</parameter></paramdef>
|
|
<paramdef>GLenum <parameter>type</parameter></paramdef>
|
|
<paramdef>const void * <parameter>data</parameter></paramdef>
|
|
</funcprototype>
|
|
</funcsynopsis>
|
|
</refsynopsisdiv>
|
|
<!-- eqn: ignoring delim $$ -->
|
|
<refsect1 id="parameters"><title>Parameters</title>
|
|
<variablelist>
|
|
<varlistentry>
|
|
<term><parameter>target</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Specifies the target texture. Must be <constant>GLU_TEXTURE_2D</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>internalFormat</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Requests the internal storage format of the texture image. The most
|
|
current version of the SGI implementation of GLU does not check this
|
|
value for validity before passing it on to the underlying OpenGL
|
|
implementation. A value that is not accepted by the OpenGL
|
|
implementation will lead to an OpenGL error. The benefit of not
|
|
checking this value at the GLU level is that OpenGL extensions can add
|
|
new internal texture formats without requiring a revision of the GLU
|
|
implementation. Older implementations of GLU check this value and
|
|
raise a GLU error if it is not 1, 2, 3, or 4 or one of the following
|
|
symbolic constants:
|
|
<constant>GLU_ALPHA</constant>,
|
|
<constant>GLU_ALPHA4</constant>,
|
|
<constant>GLU_ALPHA8</constant>,
|
|
<constant>GLU_ALPHA12</constant>,
|
|
<constant>GLU_ALPHA16</constant>,
|
|
<constant>GLU_LUMINANCE</constant>,
|
|
<constant>GLU_LUMINANCE4</constant>,
|
|
<constant>GLU_LUMINANCE8</constant>,
|
|
<constant>GLU_LUMINANCE12</constant>,
|
|
<constant>GLU_LUMINANCE16</constant>,
|
|
<constant>GLU_LUMINANCE_ALPHA</constant>,
|
|
<constant>GLU_LUMINANCE4_ALPHA4</constant>,
|
|
<constant>GLU_LUMINANCE6_ALPHA2</constant>,
|
|
<constant>GLU_LUMINANCE8_ALPHA8</constant>,
|
|
<constant>GLU_LUMINANCE12_ALPHA4</constant>,
|
|
<constant>GLU_LUMINANCE12_ALPHA12</constant>,
|
|
<constant>GLU_LUMINANCE16_ALPHA16</constant>,
|
|
<constant>GLU_INTENSITY</constant>,
|
|
<constant>GLU_INTENSITY4</constant>,
|
|
<constant>GLU_INTENSITY8</constant>,
|
|
<constant>GLU_INTENSITY12</constant>,
|
|
<constant>GLU_INTENSITY16</constant>,
|
|
<constant>GLU_RGB</constant>,
|
|
<constant>GLU_R3_G3_B2</constant>,
|
|
<constant>GLU_RGB4</constant>,
|
|
<constant>GLU_RGB5</constant>,
|
|
<constant>GLU_RGB8</constant>,
|
|
<constant>GLU_RGB10</constant>,
|
|
<constant>GLU_RGB12</constant>,
|
|
<constant>GLU_RGB16</constant>,
|
|
<constant>GLU_RGBA</constant>,
|
|
<constant>GLU_RGBA2</constant>,
|
|
<constant>GLU_RGBA4</constant>,
|
|
<constant>GLU_RGB5_A1</constant>,
|
|
<constant>GLU_RGBA8</constant>,
|
|
<constant>GLU_RGB10_A2</constant>,
|
|
<constant>GLU_RGBA12</constant>, or
|
|
<constant>GLU_RGBA16</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>width</parameter></term>
|
|
<term><parameter>height</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Specifies in pixels the width and height, respectively, of the texture image.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>format</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Specifies the format of the pixel data.
|
|
Must be one of
|
|
<constant>GLU_COLOR_INDEX</constant>,
|
|
<constant>GLU_DEPTH_COMPONENT</constant>,
|
|
<constant>GLU_RED</constant>,
|
|
<constant>GLU_GREEN</constant>,
|
|
<constant>GLU_BLUE</constant>,
|
|
<constant>GLU_ALPHA</constant>,
|
|
<constant>GLU_RGB</constant>,
|
|
<constant>GLU_RGBA</constant>,
|
|
<constant>GLU_BGR</constant>,
|
|
<constant>GLU_BGRA</constant>,
|
|
<constant>GLU_LUMINANCE</constant>, or
|
|
<constant>GLU_LUMINANCE_ALPHA</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>type</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Specifies the data type for <parameter>data</parameter>.
|
|
Must be one of
|
|
<constant>GLU_UNSIGNED_BYTE</constant>,
|
|
<constant>GLU_BYTE</constant>,
|
|
<constant>GLU_BITMAP</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT</constant>,
|
|
<constant>GLU_SHORT</constant>,
|
|
<constant>GLU_UNSIGNED_INT</constant>,
|
|
<constant>GLU_INT</constant>,
|
|
<constant>GLU_FLOAT</constant>,
|
|
<constant>GLU_UNSIGNED_BYTE_3_3_2</constant>,
|
|
<constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_6_5</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>,
|
|
<constant>GLU_UNSIGNED_INT_8_8_8_8</constant>,
|
|
<constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>,
|
|
<constant>GLU_UNSIGNED_INT_10_10_10_2</constant>, or
|
|
<constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant>.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>data</parameter></term>
|
|
<listitem>
|
|
<para>
|
|
Specifies a pointer to the image data in memory.
|
|
</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
<refsect1 id="description"><title>Description</title>
|
|
<para>
|
|
<function>gluBuild2DMipmaps</function> builds a series of prefiltered two-dimensional texture maps of decreasing
|
|
resolutions called a mipmap. This is used for the antialiasing of
|
|
texture-mapped primitives.
|
|
</para>
|
|
<para>
|
|
A return value of zero indicates success, otherwise a GLU error code is
|
|
returned (see <citerefentry><refentrytitle>gluErrorString</refentrytitle></citerefentry>).
|
|
</para>
|
|
<para>
|
|
Initially, the <parameter>width</parameter> and <parameter>height</parameter> of <parameter>data</parameter> are checked to see if they
|
|
are a power of 2. If not, a copy of <parameter>data</parameter> (not <parameter>data</parameter>), is scaled up
|
|
or down to the nearest power of 2. This copy will be used for subsequent
|
|
mipmapping operations described below. (If <parameter>width</parameter> or <parameter>height</parameter> is exactly
|
|
between powers of 2, then the copy of <parameter>data</parameter> will scale upwards.) For
|
|
example, if <parameter>width</parameter> is 57 and <parameter>height</parameter> is 23, then a copy of <parameter>data</parameter> will
|
|
scale up to 64 in <parameter>width</parameter> and down to 16 in depth, before mipmapping takes
|
|
place.
|
|
</para>
|
|
<para>
|
|
Then, proxy textures (see <citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>) are used to determine if
|
|
the implementation can fit the requested texture. If not, both dimensions
|
|
are continually halved until it fits. (If the OpenGL version is \(<= 1.0,
|
|
both maximum texture dimensions are clamped to the value returned
|
|
by <citerefentry><refentrytitle>glGetIntegerv</refentrytitle></citerefentry> with the argument <constant>GLU_MAX_TEXTURE_SIZE</constant>.)
|
|
</para>
|
|
<para>
|
|
Next, a series of mipmap levels is built by decimating a copy of <parameter>data</parameter>
|
|
in half along both dimensions until size
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 1 times 1:-->
|
|
<mml:mrow>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>
|
|
is reached. At
|
|
each level,
|
|
each texel in the halved mipmap level is an average of the corresponding
|
|
four texels in the larger mipmap level. (In the case of rectangular
|
|
images, the decimation will ultimately reach an
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: N times 1:-->
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">N</mml:mi>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>
|
|
or
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 1 times N:-->
|
|
<mml:mrow>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mi mathvariant="italic">N</mml:mi>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>
|
|
configuration. Here, two texels are averaged instead.)
|
|
</para>
|
|
<para>
|
|
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry> is called to load each of these mipmap levels.
|
|
Level 0 is a copy of <parameter>data</parameter>. The highest level is
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: {log sub 2} ( max (width,height)):-->
|
|
<mml:mrow>
|
|
<mml:mfenced open="" close="">
|
|
<mml:msub><mml:mi mathvariant="italic">log</mml:mi>
|
|
<mml:mn>2</mml:mn>
|
|
</mml:msub>
|
|
</mml:mfenced>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">max</mml:mi>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mi mathvariant="italic">width</mml:mi>
|
|
<mml:mi mathvariant="italic">height</mml:mi>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>.
|
|
For example,
|
|
if <parameter>width</parameter> is 64 and <parameter>height</parameter> is 16
|
|
and the implementation can store a texture of this size, the following
|
|
mipmap levels are built:
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 64 times 16:-->
|
|
<mml:mrow>
|
|
<mml:mn>64</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>16</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 32 times 8:-->
|
|
<mml:mrow>
|
|
<mml:mn>32</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>8</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 16 times 4:-->
|
|
<mml:mrow>
|
|
<mml:mn>16</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>4</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 8 times 2:-->
|
|
<mml:mrow>
|
|
<mml:mn>8</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>2</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 4 times 1:-->
|
|
<mml:mrow>
|
|
<mml:mn>4</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 2 times 1:-->
|
|
<mml:mrow>
|
|
<mml:mn>2</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>,
|
|
and
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: 1 times 1:-->
|
|
<mml:mrow>
|
|
<mml:mn>1</mml:mn>
|
|
<mml:mo>×</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>
|
|
These
|
|
correspond to levels 0 through 6, respectively.
|
|
</para>
|
|
<para>
|
|
See the <citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry> reference page for a description of the
|
|
acceptable values for <parameter>format</parameter> parameter. See the <citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>
|
|
reference page for a description of the acceptable values
|
|
for <parameter>type</parameter> parameter.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="notes"><title>Notes</title>
|
|
<para>
|
|
Note that there is no direct way of querying the maximum level. This can
|
|
be derived indirectly via <citerefentry><refentrytitle>glGetTexLevelParameter</refentrytitle></citerefentry>. First, query
|
|
for the width and height actually used at level 0. (The width and
|
|
height may not be equal to <parameter>width</parameter> and <parameter>height</parameter> respectively since proxy
|
|
textures might have scaled them to fit the implementation.) Then the
|
|
maximum level can be derived from the formula
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: {log sub 2}( max (width,height)):-->
|
|
<mml:mrow>
|
|
<mml:mfenced open="" close="">
|
|
<mml:msub><mml:mi mathvariant="italic">log</mml:mi>
|
|
<mml:mn>2</mml:mn>
|
|
</mml:msub>
|
|
</mml:mfenced>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">max</mml:mi>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mi mathvariant="italic">width</mml:mi>
|
|
<mml:mi mathvariant="italic">height</mml:mi>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:math></inlineequation>.
|
|
</para>
|
|
<para>
|
|
Formats <constant>GLU_BGR</constant>, and <constant>GLU_BGRA</constant>, and types
|
|
<constant>GLU_UNSIGNED_BYTE_3_3_2</constant>,
|
|
<constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_6_5</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant>,
|
|
<constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>,
|
|
<constant>GLU_UNSIGNED_INT_8_8_8_8</constant>,
|
|
<constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>,
|
|
<constant>GLU_UNSIGNED_INT_10_10_10_2</constant>, and
|
|
<constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant> are only available if the GL version
|
|
is 1.2 or greater and if the GLU version is 1.3 or greater.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="errors"><title>Errors</title>
|
|
<para>
|
|
<constant>GLU_INVALID_VALUE</constant> is returned if <parameter>width</parameter> or <parameter>height</parameter> is < 1.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_ENUM</constant> is returned if <parameter>internalFormat</parameter>, <parameter>format</parameter>, or <parameter>type</parameter> is not
|
|
legal.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_BYTE_3_3_2</constant> or <constant>GLU_UNSIGNED_BYTE_2_3_3_REV</constant>
|
|
and <parameter>format</parameter> is not <constant>GLU_RGB</constant>.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_SHORT_5_6_5</constant> or <constant>GLU_UNSIGNED_SHORT_5_6_5_REV</constant>
|
|
and <parameter>format</parameter> is not <constant>GLU_RGB</constant>.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_SHORT_4_4_4_4</constant> or <constant>GLU_UNSIGNED_SHORT_4_4_4_4_REV</constant>
|
|
and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_SHORT_5_5_5_1</constant> or <constant>GLU_UNSIGNED_SHORT_1_5_5_5_REV</constant>
|
|
and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_INT_8_8_8_8</constant> or <constant>GLU_UNSIGNED_INT_8_8_8_8_REV</constant>
|
|
and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>.
|
|
</para>
|
|
<para>
|
|
<constant>GLU_INVALID_OPERATION</constant> is returned if <parameter>type</parameter> is <constant>GLU_UNSIGNED_INT_10_10_10_2</constant> or <constant>GLU_UNSIGNED_INT_2_10_10_10_REV</constant>
|
|
and <parameter>format</parameter> is neither <constant>GLU_RGBA</constant> nor <constant>GLU_BGRA</constant>.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="seealso"><title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>gluBuild1DMipmapLevels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>gluBuild1DMipmaps</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>gluBuild2DMipmapLevels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>gluBuild3DMipmapLevels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>gluBuild3DMipmaps</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>gluErrorString</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glGetTexImage</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glGetTexLevelParameter</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glTexImage1D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glTexImage2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glTexImage3D</refentrytitle></citerefentry>
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="Copyright"><title>Copyright</title>
|
|
<para>
|
|
Copyright <trademark class="copyright"></trademark> 1991-2006
|
|
Silicon Graphics, Inc. This document is licensed under the SGI
|
|
Free Software B License. For details, see
|
|
<ulink url="http://oss.sgi.com/projects/FreeB/">http://oss.sgi.com/projects/FreeB/</ulink>.
|
|
</para>
|
|
</refsect1>
|
|
</refentry>
|