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diff --git a/libs/cairo-1.16.0/doc/public/xml/cairo-matrix.xml b/libs/cairo-1.16.0/doc/public/xml/cairo-matrix.xml new file mode 100644 index 0000000..afb0700 --- /dev/null +++ b/libs/cairo-1.16.0/doc/public/xml/cairo-matrix.xml @@ -0,0 +1,574 @@ +<?xml version='1.0' encoding='UTF-8'?> +<!DOCTYPE refentry PUBLIC "-//OASIS//DTD DocBook XML V4.2//EN" + "http://www.oasis-open.org/docbook/xml/4.2/docbookx.dtd" [ +<!ENTITY version SYSTEM "version.xml"> +]> +<refentry id="cairo-cairo-matrix-t"> +<refmeta> +<refentrytitle role="top_of_page" id="cairo-cairo-matrix-t.top_of_page">cairo_matrix_t</refentrytitle> +<manvolnum>3</manvolnum> +<refmiscinfo>CAIRO Library</refmiscinfo> +</refmeta> +<refnamediv> +<refname>cairo_matrix_t</refname> +<refpurpose>Generic matrix operations</refpurpose> +</refnamediv> + +<refsect1 id="cairo-cairo-matrix-t.functions" role="functions_proto"> +<title role="functions_proto.title">Functions</title> +<informaltable pgwide="1" frame="none"> +<tgroup cols="2"> +<colspec colname="functions_return" colwidth="150px"/> +<colspec colname="functions_name"/> +<tbody> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-init">cairo_matrix_init</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-init-identity">cairo_matrix_init_identity</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-init-translate">cairo_matrix_init_translate</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-init-scale">cairo_matrix_init_scale</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-init-rotate">cairo_matrix_init_rotate</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-translate">cairo_matrix_translate</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-scale">cairo_matrix_scale</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-rotate">cairo_matrix_rotate</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="cairo-status-t"><returnvalue>cairo_status_t</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-invert">cairo_matrix_invert</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-multiply">cairo_matrix_multiply</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-transform-distance">cairo_matrix_transform_distance</link> <phrase role="c_punctuation">()</phrase></entry></row> +<row><entry role="function_type"><link linkend="void"><returnvalue>void</returnvalue></link> +</entry><entry role="function_name"><link linkend="cairo-matrix-transform-point">cairo_matrix_transform_point</link> <phrase role="c_punctuation">()</phrase></entry></row> + +</tbody> +</tgroup> +</informaltable> +</refsect1> +<refsect1 id="cairo-cairo-matrix-t.other" role="other_proto"> +<title role="other_proto.title">Types and Values</title> +<informaltable role="enum_members_table" pgwide="1" frame="none"> +<tgroup cols="2"> +<colspec colname="name" colwidth="150px"/> +<colspec colname="description"/> +<tbody> +<row><entry role="datatype_keyword"></entry><entry role="function_name"><link linkend="cairo-matrix-t">cairo_matrix_t</link></entry></row> + +</tbody> +</tgroup> +</informaltable> +</refsect1> + + +<refsect1 id="cairo-cairo-matrix-t.description" role="desc"> +<title role="desc.title">Description</title> +<para><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> is used throughout cairo to convert between different +coordinate spaces. A <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> holds an affine transformation, +such as a scale, rotation, shear, or a combination of these. +The transformation of a point (<literal>x</literal>,<literal>y</literal>) +is given by:</para> +<programlisting> +x_new = xx * x + xy * y + x0; +y_new = yx * x + yy * y + y0; +</programlisting> +<para>The current transformation matrix of a <link linkend="cairo-t"><type>cairo_t</type></link>, represented as a +<link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link>, defines the transformation from user-space +coordinates to device-space coordinates. See <link linkend="cairo-get-matrix"><function>cairo_get_matrix()</function></link> and +<link linkend="cairo-set-matrix"><function>cairo_set_matrix()</function></link>.</para> + +</refsect1> +<refsect1 id="cairo-cairo-matrix-t.functions_details" role="details"> +<title role="details.title">Functions</title> +<refsect2 id="cairo-matrix-init" role="function" condition="since:1.0"> +<title>cairo_matrix_init ()</title> +<indexterm zone="cairo-matrix-init" role="1.0"><primary sortas="matrix_init">cairo_matrix_init</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_init (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> xx</parameter>, + <parameter><link linkend="double"><type>double</type></link> yx</parameter>, + <parameter><link linkend="double"><type>double</type></link> xy</parameter>, + <parameter><link linkend="double"><type>double</type></link> yy</parameter>, + <parameter><link linkend="double"><type>double</type></link> x0</parameter>, + <parameter><link linkend="double"><type>double</type></link> y0</parameter>);</programlisting> +<para>Sets <parameter>matrix</parameter> + to be the affine transformation given by +<parameter>xx</parameter> +, <parameter>yx</parameter> +, <parameter>xy</parameter> +, <parameter>yy</parameter> +, <parameter>x0</parameter> +, <parameter>y0</parameter> +. The transformation is given +by:</para> +<programlisting> + x_new = xx * x + xy * y + x0; + y_new = yx * x + yy * y + y0; +</programlisting> +<refsect3 id="cairo-matrix-init.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>xx</para></entry> +<entry role="parameter_description"><para>xx component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>yx</para></entry> +<entry role="parameter_description"><para>yx component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>xy</para></entry> +<entry role="parameter_description"><para>xy component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>yy</para></entry> +<entry role="parameter_description"><para>yy component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>x0</para></entry> +<entry role="parameter_description"><para>X translation component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>y0</para></entry> +<entry role="parameter_description"><para>Y translation component of the affine transformation</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-init-identity" role="function" condition="since:1.0"> +<title>cairo_matrix_init_identity ()</title> +<indexterm zone="cairo-matrix-init-identity" role="1.0"><primary sortas="matrix_init_identity">cairo_matrix_init_identity</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_init_identity (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>);</programlisting> +<para>Modifies <parameter>matrix</parameter> + to be an identity transformation.</para> +<refsect3 id="cairo-matrix-init-identity.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-init-translate" role="function" condition="since:1.0"> +<title>cairo_matrix_init_translate ()</title> +<indexterm zone="cairo-matrix-init-translate" role="1.0"><primary sortas="matrix_init_translate">cairo_matrix_init_translate</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_init_translate (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> tx</parameter>, + <parameter><link linkend="double"><type>double</type></link> ty</parameter>);</programlisting> +<para>Initializes <parameter>matrix</parameter> + to a transformation that translates by <parameter>tx</parameter> + and +<parameter>ty</parameter> + in the X and Y dimensions, respectively.</para> +<refsect3 id="cairo-matrix-init-translate.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>tx</para></entry> +<entry role="parameter_description"><para>amount to translate in the X direction</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>ty</para></entry> +<entry role="parameter_description"><para>amount to translate in the Y direction</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-init-scale" role="function" condition="since:1.0"> +<title>cairo_matrix_init_scale ()</title> +<indexterm zone="cairo-matrix-init-scale" role="1.0"><primary sortas="matrix_init_scale">cairo_matrix_init_scale</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_init_scale (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> sx</parameter>, + <parameter><link linkend="double"><type>double</type></link> sy</parameter>);</programlisting> +<para>Initializes <parameter>matrix</parameter> + to a transformation that scales by <parameter>sx</parameter> + and <parameter>sy</parameter> + +in the X and Y dimensions, respectively.</para> +<refsect3 id="cairo-matrix-init-scale.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>sx</para></entry> +<entry role="parameter_description"><para>scale factor in the X direction</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>sy</para></entry> +<entry role="parameter_description"><para>scale factor in the Y direction</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-init-rotate" role="function" condition="since:1.0"> +<title>cairo_matrix_init_rotate ()</title> +<indexterm zone="cairo-matrix-init-rotate" role="1.0"><primary sortas="matrix_init_rotate">cairo_matrix_init_rotate</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_init_rotate (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> radians</parameter>);</programlisting> +<para>Initialized <parameter>matrix</parameter> + to a transformation that rotates by <parameter>radians</parameter> +.</para> +<refsect3 id="cairo-matrix-init-rotate.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>radians</para></entry> +<entry role="parameter_description"><para>angle of rotation, in radians. The direction of rotation +is defined such that positive angles rotate in the direction from +the positive X axis toward the positive Y axis. With the default +axis orientation of cairo, positive angles rotate in a clockwise +direction.</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-translate" role="function" condition="since:1.0"> +<title>cairo_matrix_translate ()</title> +<indexterm zone="cairo-matrix-translate" role="1.0"><primary sortas="matrix_translate">cairo_matrix_translate</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_translate (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> tx</parameter>, + <parameter><link linkend="double"><type>double</type></link> ty</parameter>);</programlisting> +<para>Applies a translation by <parameter>tx</parameter> +, <parameter>ty</parameter> + to the transformation in +<parameter>matrix</parameter> +. The effect of the new transformation is to first translate +the coordinates by <parameter>tx</parameter> + and <parameter>ty</parameter> +, then apply the original transformation +to the coordinates.</para> +<refsect3 id="cairo-matrix-translate.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>tx</para></entry> +<entry role="parameter_description"><para>amount to translate in the X direction</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>ty</para></entry> +<entry role="parameter_description"><para>amount to translate in the Y direction</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-scale" role="function" condition="since:1.0"> +<title>cairo_matrix_scale ()</title> +<indexterm zone="cairo-matrix-scale" role="1.0"><primary sortas="matrix_scale">cairo_matrix_scale</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_scale (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> sx</parameter>, + <parameter><link linkend="double"><type>double</type></link> sy</parameter>);</programlisting> +<para>Applies scaling by <parameter>sx</parameter> +, <parameter>sy</parameter> + to the transformation in <parameter>matrix</parameter> +. The +effect of the new transformation is to first scale the coordinates +by <parameter>sx</parameter> + and <parameter>sy</parameter> +, then apply the original transformation to the coordinates.</para> +<refsect3 id="cairo-matrix-scale.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>sx</para></entry> +<entry role="parameter_description"><para>scale factor in the X direction</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>sy</para></entry> +<entry role="parameter_description"><para>scale factor in the Y direction</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-rotate" role="function" condition="since:1.0"> +<title>cairo_matrix_rotate ()</title> +<indexterm zone="cairo-matrix-rotate" role="1.0"><primary sortas="matrix_rotate">cairo_matrix_rotate</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_rotate (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> radians</parameter>);</programlisting> +<para>Applies rotation by <parameter>radians</parameter> + to the transformation in +<parameter>matrix</parameter> +. The effect of the new transformation is to first rotate the +coordinates by <parameter>radians</parameter> +, then apply the original transformation +to the coordinates.</para> +<refsect3 id="cairo-matrix-rotate.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>radians</para></entry> +<entry role="parameter_description"><para>angle of rotation, in radians. The direction of rotation +is defined such that positive angles rotate in the direction from +the positive X axis toward the positive Y axis. With the default +axis orientation of cairo, positive angles rotate in a clockwise +direction.</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-invert" role="function" condition="since:1.0"> +<title>cairo_matrix_invert ()</title> +<indexterm zone="cairo-matrix-invert" role="1.0"><primary sortas="matrix_invert">cairo_matrix_invert</primary></indexterm> +<programlisting language="C"><link linkend="cairo-status-t"><returnvalue>cairo_status_t</returnvalue></link> +cairo_matrix_invert (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>);</programlisting> +<para>Changes <parameter>matrix</parameter> + to be the inverse of its original value. Not +all transformation matrices have inverses; if the matrix +collapses points together (it is <firstterm>degenerate</firstterm>), +then it has no inverse and this function will fail.</para> +<refsect3 id="cairo-matrix-invert.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><refsect3 id="cairo-matrix-invert.returns" role="returns"> +<title>Returns</title> +<para> If <parameter>matrix</parameter> +has an inverse, modifies <parameter>matrix</parameter> +to +be the inverse matrix and returns <link linkend="CAIRO-STATUS-SUCCESS:CAPS"><literal>CAIRO_STATUS_SUCCESS</literal></link>. Otherwise, +returns <link linkend="CAIRO-STATUS-INVALID-MATRIX:CAPS"><literal>CAIRO_STATUS_INVALID_MATRIX</literal></link>.</para> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-multiply" role="function" condition="since:1.0"> +<title>cairo_matrix_multiply ()</title> +<indexterm zone="cairo-matrix-multiply" role="1.0"><primary sortas="matrix_multiply">cairo_matrix_multiply</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_multiply (<parameter><link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *result</parameter>, + <parameter>const <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *a</parameter>, + <parameter>const <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *b</parameter>);</programlisting> +<para>Multiplies the affine transformations in <parameter>a</parameter> + and <parameter>b</parameter> + together +and stores the result in <parameter>result</parameter> +. The effect of the resulting +transformation is to first apply the transformation in <parameter>a</parameter> + to the +coordinates and then apply the transformation in <parameter>b</parameter> + to the +coordinates.</para> +<para>It is allowable for <parameter>result</parameter> + to be identical to either <parameter>a</parameter> + or <parameter>b</parameter> +.</para> +<refsect3 id="cairo-matrix-multiply.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>result</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> in which to store the result</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>a</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>b</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-transform-distance" role="function" condition="since:1.0"> +<title>cairo_matrix_transform_distance ()</title> +<indexterm zone="cairo-matrix-transform-distance" role="1.0"><primary sortas="matrix_transform_distance">cairo_matrix_transform_distance</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_transform_distance (<parameter>const <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> *dx</parameter>, + <parameter><link linkend="double"><type>double</type></link> *dy</parameter>);</programlisting> +<para>Transforms the distance vector (<parameter>dx</parameter> +,<parameter>dy</parameter> +) by <parameter>matrix</parameter> +. This is +similar to <link linkend="cairo-matrix-transform-point"><function>cairo_matrix_transform_point()</function></link> except that the translation +components of the transformation are ignored. The calculation of +the returned vector is as follows:</para> +<programlisting> +dx2 = dx1 * a + dy1 * c; +dy2 = dx1 * b + dy1 * d; +</programlisting> +<para>Affine transformations are position invariant, so the same vector +always transforms to the same vector. If (<parameter>x1</parameter> +,<parameter>y1</parameter> +) transforms +to (<parameter>x2</parameter> +,<parameter>y2</parameter> +) then (<parameter>x1</parameter> ++<parameter>dx1</parameter> +,<parameter>y1</parameter> ++<parameter>dy1</parameter> +) will transform to +(<parameter>x1</parameter> ++<parameter>dx2</parameter> +,<parameter>y1</parameter> ++<parameter>dy2</parameter> +) for all values of <parameter>x1</parameter> + and <parameter>x2</parameter> +.</para> +<refsect3 id="cairo-matrix-transform-distance.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>dx</para></entry> +<entry role="parameter_description"><para>X component of a distance vector. An in/out parameter</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>dy</para></entry> +<entry role="parameter_description"><para>Y component of a distance vector. An in/out parameter</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> +<refsect2 id="cairo-matrix-transform-point" role="function" condition="since:1.0"> +<title>cairo_matrix_transform_point ()</title> +<indexterm zone="cairo-matrix-transform-point" role="1.0"><primary sortas="matrix_transform_point">cairo_matrix_transform_point</primary></indexterm> +<programlisting language="C"><link linkend="void"><returnvalue>void</returnvalue></link> +cairo_matrix_transform_point (<parameter>const <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> *matrix</parameter>, + <parameter><link linkend="double"><type>double</type></link> *x</parameter>, + <parameter><link linkend="double"><type>double</type></link> *y</parameter>);</programlisting> +<para>Transforms the point (<parameter>x</parameter> +, <parameter>y</parameter> +) by <parameter>matrix</parameter> +.</para> +<refsect3 id="cairo-matrix-transform-point.parameters" role="parameters"> +<title>Parameters</title> +<informaltable role="parameters_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="parameters_name" colwidth="150px"/> +<colspec colname="parameters_description"/> +<colspec colname="parameters_annotations" colwidth="200px"/> +<tbody> +<row><entry role="parameter_name"><para>matrix</para></entry> +<entry role="parameter_description"><para>a <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link></para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>x</para></entry> +<entry role="parameter_description"><para>X position. An in/out parameter</para></entry> +<entry role="parameter_annotations"></entry></row> +<row><entry role="parameter_name"><para>y</para></entry> +<entry role="parameter_description"><para>Y position. An in/out parameter</para></entry> +<entry role="parameter_annotations"></entry></row> +</tbody></tgroup></informaltable> +</refsect3><para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> + +</refsect1> +<refsect1 id="cairo-cairo-matrix-t.other_details" role="details"> +<title role="details.title">Types and Values</title> +<refsect2 id="cairo-matrix-t" role="struct" condition="since:1.0"> +<title>cairo_matrix_t</title> +<indexterm zone="cairo-matrix-t" role="1.0"><primary sortas="matrix_t">cairo_matrix_t</primary></indexterm> +<programlisting language="C">typedef struct { + double xx; double yx; + double xy; double yy; + double x0; double y0; +} cairo_matrix_t; +</programlisting> +<para>A <link linkend="cairo-matrix-t"><type>cairo_matrix_t</type></link> holds an affine transformation, such as a scale, +rotation, shear, or a combination of those. The transformation of +a point (x, y) is given by:</para> +<programlisting> + x_new = xx * x + xy * y + x0; + y_new = yx * x + yy * y + y0; +</programlisting> +<refsect3 id="cairo-matrix-t.members" role="struct_members"> +<title>Members</title> +<informaltable role="struct_members_table" pgwide="1" frame="none"> +<tgroup cols="3"> +<colspec colname="struct_members_name" colwidth="300px"/> +<colspec colname="struct_members_description"/> +<colspec colname="struct_members_annotations" colwidth="200px"/> +<tbody> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.xx">xx</structfield>;</para></entry> +<entry role="struct_member_description"><para>xx component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.yx">yx</structfield>;</para></entry> +<entry role="struct_member_description"><para>yx component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.xy">xy</structfield>;</para></entry> +<entry role="struct_member_description"><para>xy component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.yy">yy</structfield>;</para></entry> +<entry role="struct_member_description"><para>yy component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.x0">x0</structfield>;</para></entry> +<entry role="struct_member_description"><para>X translation component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +<row role="member"><entry role="struct_member_name"><para><link linkend="double"><type>double</type></link> <structfield id="cairo-matrix-t.y0">y0</structfield>;</para></entry> +<entry role="struct_member_description"><para>Y translation component of the affine transformation</para></entry> +<entry role="struct_member_annotations"></entry> +</row> +</tbody></tgroup></informaltable> +</refsect3> +<para role="since">Since: <link linkend="api-index-1.0">1.0</link></para></refsect2> + +</refsect1> +<refsect1 id="cairo-cairo-matrix-t.see-also"> +<title>See Also</title> +<para><link linkend="cairo-t"><type>cairo_t</type></link></para> + +</refsect1> + +</refentry> |