609 lines
32 KiB
XML
609 lines
32 KiB
XML
<?xml version="1.0" encoding="UTF-8"?>
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<!DOCTYPE book PUBLIC "-//OASIS//DTD DocBook MathML Module V1.1b1//EN"
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"http://www.oasis-open.org/docbook/xml/mathml/1.1CR1/dbmathml.dtd">
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<refentry id="glCopyPixels">
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<refmeta>
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<refmetainfo>
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<copyright>
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<year>1991-2006</year>
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<holder>Silicon Graphics, Inc.</holder>
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</copyright>
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</refmetainfo>
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<refentrytitle>glCopyPixels</refentrytitle>
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<manvolnum>3G</manvolnum>
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</refmeta>
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<refnamediv>
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<refname>glCopyPixels</refname>
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<refpurpose>copy pixels in the frame buffer</refpurpose>
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</refnamediv>
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<refsynopsisdiv><title>C Specification</title>
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<funcsynopsis>
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<funcprototype>
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<funcdef>void <function>glCopyPixels</function></funcdef>
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<paramdef>GLint <parameter>x</parameter></paramdef>
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<paramdef>GLint <parameter>y</parameter></paramdef>
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<paramdef>GLsizei <parameter>width</parameter></paramdef>
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<paramdef>GLsizei <parameter>height</parameter></paramdef>
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<paramdef>GLenum <parameter>type</parameter></paramdef>
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</funcprototype>
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</funcsynopsis>
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</refsynopsisdiv>
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<!-- eqn: ignoring delim $$ -->
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<refsect1 id="parameters"><title>Parameters</title>
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<variablelist>
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<varlistentry>
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<term><parameter>x</parameter></term>
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<term><parameter>y</parameter></term>
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<listitem>
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<para>
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Specify the window coordinates of the lower left corner
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of the rectangular region of pixels to be copied.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>width</parameter></term>
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<term><parameter>height</parameter></term>
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<listitem>
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<para>
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Specify the dimensions of the rectangular region of pixels to be copied.
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Both must be nonnegative.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><parameter>type</parameter></term>
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<listitem>
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<para>
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Specifies whether color values,
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depth values,
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or stencil values are to be copied.
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Symbolic constants
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<constant>GL_COLOR</constant>,
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<constant>GL_DEPTH</constant>,
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and <constant>GL_STENCIL</constant> are accepted.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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</refsect1>
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<refsect1 id="description"><title>Description</title>
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<para>
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<function>glCopyPixels</function> copies a screen-aligned rectangle of pixels
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from the specified frame buffer location to a region relative to the
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current raster position.
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Its operation is well defined only if the entire pixel source region
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is within the exposed portion of the window.
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Results of copies from outside the window,
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or from regions of the window that are not exposed,
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are hardware dependent and undefined.
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</para>
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<para>
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<parameter>x</parameter> and <parameter>y</parameter> specify the window coordinates of
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the lower left corner of the rectangular region to be copied.
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<parameter>width</parameter> and <parameter>height</parameter> specify the dimensions of the
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rectangular region to be copied.
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Both <parameter>width</parameter> and <parameter>height</parameter> must not be negative.
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</para>
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<para>
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Several parameters control the processing of the pixel data
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while it is being copied.
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These parameters are set with three commands:
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<citerefentry><refentrytitle>glPixelTransfer</refentrytitle></citerefentry>,
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<citerefentry><refentrytitle>glPixelMap</refentrytitle></citerefentry>, and
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<citerefentry><refentrytitle>glPixelZoom</refentrytitle></citerefentry>.
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This reference page describes the effects on <function>glCopyPixels</function> of most,
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but not all, of the parameters specified by these three commands.
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</para>
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<para>
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<function>glCopyPixels</function> copies values from each pixel with the lower left-hand corner at
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<inlineequation><mml:math>
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<!-- eqn: (x + i, y + j):-->
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:mi mathvariant="italic">x</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:mrow>
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<mml:mrow>
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<mml:mi mathvariant="italic">y</mml:mi>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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</mml:mrow>
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</mml:mfenced>
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</mml:math></inlineequation>
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for
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<inlineequation><mml:math>
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<!-- eqn: 0 <= i < width:-->
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<mml:mrow>
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<mml:mn>0</mml:mn>
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<mml:mo><=</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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<mml:mo><</mml:mo>
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<mml:mi mathvariant="italic">width</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>
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and
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<inlineequation><mml:math>
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<!-- eqn: 0 <= j < height:-->
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<mml:mrow>
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<mml:mn>0</mml:mn>
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<mml:mo><=</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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<mml:mo><</mml:mo>
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<mml:mi mathvariant="italic">height</mml:mi>
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</mml:mrow>
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</mml:math></inlineequation>.
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This pixel is said to be the
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<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
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pixel in the
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<inlineequation><mml:math><mml:mi mathvariant="italic">j</mml:mi></mml:math></inlineequation>th
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row.
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Pixels are copied in row order from the lowest to the highest row,
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left to right in each row.
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</para>
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<para>
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<parameter>type</parameter> specifies whether color, depth, or stencil data is to be copied.
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The details of the transfer for each data type are as follows:
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</para>
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<variablelist>
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<varlistentry>
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<term><constant>GL_COLOR</constant></term>
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<listitem>
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<para>
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Indices or RGBA colors are read from the buffer currently specified as the
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read source buffer (see <citerefentry><refentrytitle>glReadBuffer</refentrytitle></citerefentry>).
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If the GL is in color index mode,
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each index that is read from this buffer is converted
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to a fixed-point format with an unspecified
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number of bits to the right of the binary point.
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Each index is then shifted left by <constant>GL_INDEX_SHIFT</constant> bits,
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and added to <constant>GL_INDEX_OFFSET</constant>.
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If <constant>GL_INDEX_SHIFT</constant> is negative,
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the shift is to the right.
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In either case, zero bits fill otherwise unspecified bit locations in the
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result.
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If <constant>GL_MAP_COLOR</constant> is true,
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the index is replaced with the value that it references in lookup table
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<constant>GL_PIXEL_MAP_I_TO_I</constant>.
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Whether the lookup replacement of the index is done or not,
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the integer part of the index is then ANDed with
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<inlineequation><mml:math>
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<!-- eqn: 2 sup b -1:-->
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<mml:mrow>
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<mml:msup><mml:mn>2</mml:mn>
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<mml:mi mathvariant="italic">b</mml:mi>
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</mml:msup>
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<mml:mo>-</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math><mml:mi mathvariant="italic">b</mml:mi></mml:math></inlineequation>
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is the number of bits in a color index buffer.
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</para>
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<para>
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If the GL is in RGBA mode,
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the red, green, blue, and alpha components of each pixel that is read
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are converted to an internal floating-point format with unspecified
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precision.
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The conversion maps the largest representable component value to 1.0,
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and component value 0 to 0.0.
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The resulting floating-point color values are then multiplied
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by <constant>GL_c_SCALE</constant> and added to <constant>GL_c_BIAS</constant>,
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where <emphasis>c</emphasis> is RED, GREEN, BLUE, and ALPHA
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for the respective color components.
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The results are clamped to the range [0,1].
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If <constant>GL_MAP_COLOR</constant> is true,
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each color component is scaled by the size of lookup table
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<constant>GL_PIXEL_MAP_c_TO_c</constant>,
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then replaced by the value that it references in that table.
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<emphasis>c</emphasis> is R, G, B, or A.
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</para>
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<para>
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If the <code>ARB_imaging</code> extension is supported, the color values may
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be
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additionally processed by color-table lookups, color-matrix
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transformations, and convolution filters.
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</para>
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<para>
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The GL then converts the resulting indices or RGBA colors to fragments
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by attaching the current raster position <emphasis>z</emphasis> coordinate and
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texture coordinates to each pixel,
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then assigning window coordinates
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<inlineequation><mml:math>
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<!-- eqn: (x sub r + i , y sub r + j):-->
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:mrow>
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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</mml:mrow>
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</mml:mfenced>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math>
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<!-- eqn: (x sub r , y sub r):-->
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<mml:mfenced open="(" close=")">
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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</mml:mfenced>
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</mml:math></inlineequation>
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is the current raster position,
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and the pixel was the
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<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
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pixel in the
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<inlineequation><mml:math><mml:mi mathvariant="italic">j</mml:mi></mml:math></inlineequation>th
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row.
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These pixel fragments are then treated just like the fragments generated by
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rasterizing points, lines, or polygons.
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Texture mapping,
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fog,
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and all the fragment operations are applied before the fragments are written
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to the frame buffer.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_DEPTH</constant></term>
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<listitem>
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<para>
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Depth values are read from the depth buffer and
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converted directly to an internal floating-point format
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with unspecified precision.
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The resulting floating-point depth value is then multiplied
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by <constant>GL_DEPTH_SCALE</constant> and added to <constant>GL_DEPTH_BIAS</constant>.
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The result is clamped to the range [0,1].
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</para>
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<para>
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The GL then converts the resulting depth components to fragments
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by attaching the current raster position color or color index and
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texture coordinates to each pixel,
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then assigning window coordinates
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<inlineequation><mml:math>
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<!-- eqn: (x sub r + i , y sub r + j):-->
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:mrow>
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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</mml:mrow>
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</mml:mfenced>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math>
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<!-- eqn: (x sub r , y sub r):-->
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<mml:mfenced open="(" close=")">
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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</mml:mfenced>
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</mml:math></inlineequation>
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is the current raster position,
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and the pixel was the
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<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
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pixel in the
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<inlineequation><mml:math><mml:mi mathvariant="italic">j</mml:mi></mml:math></inlineequation>th
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row.
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These pixel fragments are then treated just like the fragments generated by
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rasterizing points, lines, or polygons.
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Texture mapping,
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fog,
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and all the fragment operations are applied before the fragments are written
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to the frame buffer.
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</para>
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</listitem>
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</varlistentry>
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<varlistentry>
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<term><constant>GL_STENCIL</constant></term>
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<listitem>
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<para>
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Stencil indices are read from the stencil buffer and
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converted to an internal fixed-point format
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with an unspecified number of bits to the right of the binary point.
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Each fixed-point index is then shifted left by <constant>GL_INDEX_SHIFT</constant> bits,
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and added to <constant>GL_INDEX_OFFSET</constant>.
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If <constant>GL_INDEX_SHIFT</constant> is negative,
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the shift is to the right.
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In either case, zero bits fill otherwise unspecified bit locations in the
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result.
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If <constant>GL_MAP_STENCIL</constant> is true,
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the index is replaced with the value that it references in lookup table
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<constant>GL_PIXEL_MAP_S_TO_S</constant>.
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Whether the lookup replacement of the index is done or not,
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the integer part of the index is then ANDed with
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<inlineequation><mml:math>
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<!-- eqn: 2 sup b -1:-->
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<mml:mrow>
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<mml:msup><mml:mn>2</mml:mn>
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<mml:mi mathvariant="italic">b</mml:mi>
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</mml:msup>
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<mml:mo>-</mml:mo>
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<mml:mn>1</mml:mn>
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</mml:mrow>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math><mml:mi mathvariant="italic">b</mml:mi></mml:math></inlineequation>
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is the number of bits in the stencil buffer.
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The resulting stencil indices are then written to the stencil buffer
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such that the index read from the
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<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
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location of the
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<inlineequation><mml:math><mml:mi mathvariant="italic">j</mml:mi></mml:math></inlineequation>th
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row
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is written to location
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<inlineequation><mml:math>
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<!-- eqn: (x sub r + i , y sub r + j):-->
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:mrow>
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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</mml:mrow>
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</mml:mfenced>
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</mml:math></inlineequation>,
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where
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<inlineequation><mml:math>
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<!-- eqn: (x sub r , y sub r):-->
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<mml:mfenced open="(" close=")">
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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</mml:mfenced>
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</mml:math></inlineequation>
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is the current raster position.
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Only the pixel ownership test,
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the scissor test,
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and the stencil writemask affect these write operations.
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</para>
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</listitem>
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</varlistentry>
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</variablelist>
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<para>
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The rasterization described thus far assumes pixel zoom factors of 1.0.
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If
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<citerefentry><refentrytitle>glPixelZoom</refentrytitle></citerefentry> is used to change the
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<inlineequation><mml:math><mml:mi mathvariant="italic">x</mml:mi></mml:math></inlineequation>
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and
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<inlineequation><mml:math><mml:mi mathvariant="italic">y</mml:mi></mml:math></inlineequation>
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pixel zoom factors,
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pixels are converted to fragments as follows.
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If
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<inlineequation><mml:math>
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<!-- eqn: (x sub r, y sub r):-->
|
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<mml:mfenced open="(" close=")">
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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</mml:mfenced>
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</mml:math></inlineequation>
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is the current raster position,
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and a given pixel is in the
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<inlineequation><mml:math><mml:mi mathvariant="italic">i</mml:mi></mml:math></inlineequation>th
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location in the
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<inlineequation><mml:math><mml:mi mathvariant="italic">j</mml:mi></mml:math></inlineequation>th
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row of the source
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pixel rectangle,
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then fragments are generated for pixels whose centers are in the rectangle
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with corners at
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</para>
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<para>
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<inlineequation><mml:math>
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<!-- eqn: (x sub r + {zoom sub x} i, y sub r + {zoom sub y} j):-->
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<mml:mfenced open="(" close=")">
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
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</mml:msub>
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<mml:mo>+</mml:mo>
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<mml:mfenced open="" close="">
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<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
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<mml:mi mathvariant="italic">x</mml:mi>
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</mml:msub>
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</mml:mfenced>
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<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">i</mml:mi>
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</mml:mrow>
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<mml:mrow>
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<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
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<mml:mi mathvariant="italic">r</mml:mi>
|
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</mml:msub>
|
|
<mml:mo>+</mml:mo>
|
|
<mml:mfenced open="" close="">
|
|
<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
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<mml:mi mathvariant="italic">y</mml:mi>
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</mml:msub>
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|
</mml:mfenced>
|
|
<mml:mo>⁢</mml:mo>
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<mml:mi mathvariant="italic">j</mml:mi>
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</mml:mrow>
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</mml:mfenced>
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</mml:math></inlineequation>
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</para>
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<para>
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and
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</para>
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<para>
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|
<inlineequation><mml:math>
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|
<!-- eqn: (x sub r + {zoom sub x} (i + 1), y sub r + {zoom sub y} ( j + 1 )):-->
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mrow>
|
|
<mml:msub><mml:mi mathvariant="italic">x</mml:mi>
|
|
<mml:mi mathvariant="italic">r</mml:mi>
|
|
</mml:msub>
|
|
<mml:mo>+</mml:mo>
|
|
<mml:mrow>
|
|
<mml:mfenced open="" close="">
|
|
<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
|
|
<mml:mi mathvariant="italic">x</mml:mi>
|
|
</mml:msub>
|
|
</mml:mfenced>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">i</mml:mi>
|
|
<mml:mo>+</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mrow>
|
|
<mml:mrow>
|
|
<mml:msub><mml:mi mathvariant="italic">y</mml:mi>
|
|
<mml:mi mathvariant="italic">r</mml:mi>
|
|
</mml:msub>
|
|
<mml:mo>+</mml:mo>
|
|
<mml:mrow>
|
|
<mml:mfenced open="" close="">
|
|
<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
|
|
<mml:mi mathvariant="italic">y</mml:mi>
|
|
</mml:msub>
|
|
</mml:mfenced>
|
|
<mml:mo>⁡</mml:mo>
|
|
<mml:mfenced open="(" close=")">
|
|
<mml:mrow>
|
|
<mml:mi mathvariant="italic">j</mml:mi>
|
|
<mml:mo>+</mml:mo>
|
|
<mml:mn>1</mml:mn>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:mrow>
|
|
</mml:mrow>
|
|
</mml:mfenced>
|
|
</mml:math></inlineequation>
|
|
</para>
|
|
<para>
|
|
where
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: zoom sub x:-->
|
|
<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
|
|
<mml:mi mathvariant="italic">x</mml:mi>
|
|
</mml:msub>
|
|
</mml:math></inlineequation>
|
|
is the value of <constant>GL_ZOOM_X</constant> and
|
|
<inlineequation><mml:math>
|
|
<!-- eqn: zoom sub y:-->
|
|
<mml:msub><mml:mi mathvariant="italic">zoom</mml:mi>
|
|
<mml:mi mathvariant="italic">y</mml:mi>
|
|
</mml:msub>
|
|
</mml:math></inlineequation>
|
|
is the value of <constant>GL_ZOOM_Y</constant>.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="examples"><title>Examples</title>
|
|
<para>
|
|
To copy the color pixel in the lower left corner of the window to the current raster position,
|
|
use
|
|
</para>
|
|
<para>
|
|
<programlisting>
|
|
glCopyPixels(0, 0, 1, 1, <constant>GL_COLOR</constant>);
|
|
</programlisting>
|
|
</para>
|
|
<para>
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="notes"><title>Notes</title>
|
|
<para>
|
|
Modes specified by <citerefentry><refentrytitle>glPixelStore</refentrytitle></citerefentry> have no effect on the operation
|
|
of <function>glCopyPixels</function>.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="errors"><title>Errors</title>
|
|
<para>
|
|
<constant>GL_INVALID_ENUM</constant> is generated if <parameter>type</parameter> is not an accepted value.
|
|
</para>
|
|
<para>
|
|
<constant>GL_INVALID_VALUE</constant> is generated if either <parameter>width</parameter> or <parameter>height</parameter> is negative.
|
|
</para>
|
|
<para>
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if <parameter>type</parameter> is <constant>GL_DEPTH</constant>
|
|
and there is no depth buffer.
|
|
</para>
|
|
<para>
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if <parameter>type</parameter> is <constant>GL_STENCIL</constant>
|
|
and there is no stencil buffer.
|
|
</para>
|
|
<para>
|
|
<constant>GL_INVALID_OPERATION</constant> is generated if <function>glCopyPixels</function>
|
|
is executed between the execution of <citerefentry><refentrytitle>glBegin</refentrytitle></citerefentry>
|
|
and the corresponding execution of <citerefentry><refentrytitle>glEnd</refentrytitle></citerefentry>.
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="associatedgets"><title>Associated Gets</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_CURRENT_RASTER_POSITION</constant>
|
|
</para>
|
|
<para>
|
|
<citerefentry><refentrytitle>glGet</refentrytitle></citerefentry> with argument <constant>GL_CURRENT_RASTER_POSITION_VALID</constant>
|
|
</para>
|
|
</refsect1>
|
|
<refsect1 id="seealso"><title>See Also</title>
|
|
<para>
|
|
<citerefentry><refentrytitle>glColorTable</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glConvolutionFilter1D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glConvolutionFilter2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glDepthFunc</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glDrawBuffer</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glDrawPixels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glMatrixMode</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glPixelMap</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glPixelTransfer</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glPixelZoom</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glRasterPos</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glReadBuffer</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glReadPixels</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glSeparableFilter2D</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glStencilFunc</refentrytitle></citerefentry>,
|
|
<citerefentry><refentrytitle>glWindowPos</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>
|