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<p>A Transformation matrix.
<a href="classCairo_1_1Matrix.html#details">More...</a></p>
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Inheritance diagram for Cairo::Matrix:</div>
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<table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="pub-methods"></a>
Public Member Functions</h2></td></tr>
<tr class="memitem:a69297a4b8adc2bdecece4c372edc1e63"><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a69297a4b8adc2bdecece4c372edc1e63">Matrix</a> ()</td></tr>
<tr class="memdesc:a69297a4b8adc2bdecece4c372edc1e63"><td class="mdescLeft"> </td><td class="mdescRight">Creates an uninitialized matrix. <a href="#a69297a4b8adc2bdecece4c372edc1e63">More...</a><br /></td></tr>
<tr class="separator:a69297a4b8adc2bdecece4c372edc1e63"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a90a6fe36d7744bfd607c2b37435ca8e6"><td class="memItemLeft" align="right" valign="top"> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a90a6fe36d7744bfd607c2b37435ca8e6">Matrix</a> (double xx, double yx, double xy, double yy, double x0, double y0)</td></tr>
<tr class="memdesc:a90a6fe36d7744bfd607c2b37435ca8e6"><td class="mdescLeft"> </td><td class="mdescRight">Creates a matrix Sets to be the affine transformation given by xx, yx, xy, yy, x0, y0. <a href="#a90a6fe36d7744bfd607c2b37435ca8e6">More...</a><br /></td></tr>
<tr class="separator:a90a6fe36d7744bfd607c2b37435ca8e6"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:aec65d01b5251144dc20708f0b05940f6"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#aec65d01b5251144dc20708f0b05940f6">translate</a> (double tx, double ty)</td></tr>
<tr class="memdesc:aec65d01b5251144dc20708f0b05940f6"><td class="mdescLeft"> </td><td class="mdescRight">Applies a translation by tx, ty to the transformation in matrix. <a href="#aec65d01b5251144dc20708f0b05940f6">More...</a><br /></td></tr>
<tr class="separator:aec65d01b5251144dc20708f0b05940f6"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a697c488fb323f4a6edda4edd0533c95c"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a697c488fb323f4a6edda4edd0533c95c">scale</a> (double sx, double sy)</td></tr>
<tr class="memdesc:a697c488fb323f4a6edda4edd0533c95c"><td class="mdescLeft"> </td><td class="mdescRight">Applies scaling by sx, sy to the transformation in matrix. <a href="#a697c488fb323f4a6edda4edd0533c95c">More...</a><br /></td></tr>
<tr class="separator:a697c488fb323f4a6edda4edd0533c95c"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a98b3feae5ff15937c764ebec846efb33"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a98b3feae5ff15937c764ebec846efb33">rotate</a> (double radians)</td></tr>
<tr class="memdesc:a98b3feae5ff15937c764ebec846efb33"><td class="mdescLeft"> </td><td class="mdescRight">Applies rotation by radians to the transformation in matrix. <a href="#a98b3feae5ff15937c764ebec846efb33">More...</a><br /></td></tr>
<tr class="separator:a98b3feae5ff15937c764ebec846efb33"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a3ad532fa3b90ac4019d6a535ffde0cd4"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a3ad532fa3b90ac4019d6a535ffde0cd4">invert</a> ()</td></tr>
<tr class="memdesc:a3ad532fa3b90ac4019d6a535ffde0cd4"><td class="mdescLeft"> </td><td class="mdescRight">Changes matrix to be the inverse of it's original value. <a href="#a3ad532fa3b90ac4019d6a535ffde0cd4">More...</a><br /></td></tr>
<tr class="separator:a3ad532fa3b90ac4019d6a535ffde0cd4"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a748df1dafe6a35422fa51b31f6932587"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a748df1dafe6a35422fa51b31f6932587">multiply</a> (<a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& a, <a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& b)</td></tr>
<tr class="memdesc:a748df1dafe6a35422fa51b31f6932587"><td class="mdescLeft"> </td><td class="mdescRight">Multiplies the affine transformations in a and b together and stores the result in this matrix. <a href="#a748df1dafe6a35422fa51b31f6932587">More...</a><br /></td></tr>
<tr class="separator:a748df1dafe6a35422fa51b31f6932587"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a7966181b002249878a895bb3911f39e8"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a7966181b002249878a895bb3911f39e8">transform_distance</a> (double& dx, double& dy) const </td></tr>
<tr class="memdesc:a7966181b002249878a895bb3911f39e8"><td class="mdescLeft"> </td><td class="mdescRight">Transforms the distance vector (dx,dy) by matrix. <a href="#a7966181b002249878a895bb3911f39e8">More...</a><br /></td></tr>
<tr class="separator:a7966181b002249878a895bb3911f39e8"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:af0b0ac8dd645036fdd4a3ee54cdcaca6"><td class="memItemLeft" align="right" valign="top">void </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#af0b0ac8dd645036fdd4a3ee54cdcaca6">transform_point</a> (double& x, double& y) const </td></tr>
<tr class="memdesc:af0b0ac8dd645036fdd4a3ee54cdcaca6"><td class="mdescLeft"> </td><td class="mdescRight">Transforms the point (x, y) by this matrix. <a href="#af0b0ac8dd645036fdd4a3ee54cdcaca6">More...</a><br /></td></tr>
<tr class="separator:af0b0ac8dd645036fdd4a3ee54cdcaca6"><td class="memSeparator" colspan="2"> </td></tr>
</table><table class="memberdecls">
<tr class="heading"><td colspan="2"><h2 class="groupheader"><a name="related"></a>
Related Functions</h2></td></tr>
<tr><td class="ititle" colspan="2"><p>(Note that these are not member functions.) </p>
</td></tr>
<tr class="memitem:a293cbaf13eb86244648cb558b2cf7dd3"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a293cbaf13eb86244648cb558b2cf7dd3">identity_matrix</a> ()</td></tr>
<tr class="memdesc:a293cbaf13eb86244648cb558b2cf7dd3"><td class="mdescLeft"> </td><td class="mdescRight">Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to the identity matrix. <a href="#a293cbaf13eb86244648cb558b2cf7dd3">More...</a><br /></td></tr>
<tr class="separator:a293cbaf13eb86244648cb558b2cf7dd3"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ae638d4c68c7f26f9760335eb42680cea"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#ae638d4c68c7f26f9760335eb42680cea">translation_matrix</a> (double tx, double ty)</td></tr>
<tr class="memdesc:ae638d4c68c7f26f9760335eb42680cea"><td class="mdescLeft"> </td><td class="mdescRight">Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that translates by tx and ty in the X and Y dimensions, respectively. <a href="#ae638d4c68c7f26f9760335eb42680cea">More...</a><br /></td></tr>
<tr class="separator:ae638d4c68c7f26f9760335eb42680cea"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ac217befdf043bdb5f1c29632e60cbdef"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#ac217befdf043bdb5f1c29632e60cbdef">scaling_matrix</a> (double sx, double sy)</td></tr>
<tr class="memdesc:ac217befdf043bdb5f1c29632e60cbdef"><td class="mdescLeft"> </td><td class="mdescRight">Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that scales by sx and sy in the X and Y dimensions, respectively. <a href="#ac217befdf043bdb5f1c29632e60cbdef">More...</a><br /></td></tr>
<tr class="separator:ac217befdf043bdb5f1c29632e60cbdef"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:a324cadc45a2fe7424cb0d0d6b73ccbe8"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#a324cadc45a2fe7424cb0d0d6b73ccbe8">rotation_matrix</a> (double radians)</td></tr>
<tr class="memdesc:a324cadc45a2fe7424cb0d0d6b73ccbe8"><td class="mdescLeft"> </td><td class="mdescRight">Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that rotates by radians. <a href="#a324cadc45a2fe7424cb0d0d6b73ccbe8">More...</a><br /></td></tr>
<tr class="separator:a324cadc45a2fe7424cb0d0d6b73ccbe8"><td class="memSeparator" colspan="2"> </td></tr>
<tr class="memitem:ab0bbb2ec9c1451f42f0270652df8cada"><td class="memItemLeft" align="right" valign="top"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> </td><td class="memItemRight" valign="bottom"><a class="el" href="classCairo_1_1Matrix.html#ab0bbb2ec9c1451f42f0270652df8cada">operator*</a> (const <a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& a, const <a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& b)</td></tr>
<tr class="memdesc:ab0bbb2ec9c1451f42f0270652df8cada"><td class="mdescLeft"> </td><td class="mdescRight">Multiplies the affine transformations in a and b together and returns the result. <a href="#ab0bbb2ec9c1451f42f0270652df8cada">More...</a><br /></td></tr>
<tr class="separator:ab0bbb2ec9c1451f42f0270652df8cada"><td class="memSeparator" colspan="2"> </td></tr>
</table>
<a name="details" id="details"></a><h2 class="groupheader">Detailed Description</h2>
<div class="textblock"><p>A Transformation matrix. </p>
<p><a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Cairo::Matrix</a> is used throughout cairomm to convert between different coordinate spaces. A <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> holds an affine transformation, such as a scale, rotation, shear, or a combination of these. The transformation of a point (x,y) is given by:</p>
<div class="fragment"><div class="line">x_new = xx * x + xy * y + x0;</div>
<div class="line">y_new = yx * x + yy * y + y0;</div>
</div><!-- fragment --><p>The current transformation matrix of a <a class="el" href="classCairo_1_1Context.html" title="Context is the main class used to draw in cairomm. ">Context</a>, represented as a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a>, defines the transformation from user-space coordinates to device-space coordinates. </p><dl class="section see"><dt>See also</dt><dd><a class="el" href="classCairo_1_1Context.html#a03b21f4a3a44e28086c3a25075fdcea1" title="Stores the current transformation matrix (CTM) into matrix. ">Context::get_matrix()</a> </dd>
<dd>
<a class="el" href="classCairo_1_1Context.html#ac2eafbac5591e569d22495f7920d60d2" title="Modifies the current transformation matrix (CTM) by setting it equal to matrix. ">Context::set_matrix()</a> </dd></dl>
</div><h2 class="groupheader">Constructor & Destructor Documentation</h2>
<a class="anchor" id="a69297a4b8adc2bdecece4c372edc1e63"></a>
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<td class="memname">Cairo::Matrix::Matrix </td>
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<p>Creates an uninitialized matrix. </p>
<p>If you want a matrix initialized to a certain value, either specify the values explicitly with the other constructor or use one of the free functions for initializing matrices with specific scales, rotations, etc.</p>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="classCairo_1_1Matrix.html#a293cbaf13eb86244648cb558b2cf7dd3" title="Returns a Matrix initialized to the identity matrix. ">identity_matrix()</a> </dd>
<dd>
<a class="el" href="classCairo_1_1Matrix.html#a324cadc45a2fe7424cb0d0d6b73ccbe8" title="Returns a Matrix initialized to a transformation that rotates by radians. ">rotation_matrix()</a> </dd>
<dd>
<a class="el" href="classCairo_1_1Matrix.html#ae638d4c68c7f26f9760335eb42680cea" title="Returns a Matrix initialized to a transformation that translates by tx and ty in the X and Y dimensio...">translation_matrix()</a> </dd>
<dd>
<a class="el" href="classCairo_1_1Matrix.html#ac217befdf043bdb5f1c29632e60cbdef" title="Returns a Matrix initialized to a transformation that scales by sx and sy in the X and Y dimensions...">scaling_matrix()</a> </dd></dl>
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<td class="memname">Cairo::Matrix::Matrix </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>xx</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>yx</em>, </td>
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<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>xy</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>yy</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>x0</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>y0</em> </td>
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<td></td>
<td>)</td>
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<p>Creates a matrix Sets to be the affine transformation given by xx, yx, xy, yy, x0, y0. </p>
<p>The transformation is given by:</p>
<div class="fragment"><div class="line">x_new = xx * x + xy * y + x0;</div>
<div class="line">y_new = yx * x + yy * y + y0;</div>
</div><!-- fragment --><dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">xx</td><td>xx component of the affine transformation </td></tr>
<tr><td class="paramname">yx</td><td>yx component of the affine transformation </td></tr>
<tr><td class="paramname">xy</td><td>xy component of the affine transformation </td></tr>
<tr><td class="paramname">yy</td><td>yy component of the affine transformation </td></tr>
<tr><td class="paramname">x0</td><td>X translation component of the affine transformation </td></tr>
<tr><td class="paramname">y0</td><td>Y translation component of the affine transformation </td></tr>
</table>
</dd>
</dl>
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<h2 class="groupheader">Member Function Documentation</h2>
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<td class="memname">void Cairo::Matrix::invert </td>
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<p>Changes matrix to be the inverse of it's original value. </p>
<p>Not all transformation matrices have inverses; if the matrix collapses points together (it is degenerate), then it has no inverse and this function will throw an exception.</p>
<dl class="exception"><dt>Exceptions</dt><dd>
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<tr><td class="paramname"></td><td></td></tr>
</table>
</dd>
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<td class="memname">void Cairo::Matrix::multiply </td>
<td>(</td>
<td class="paramtype"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& </td>
<td class="paramname"><em>a</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& </td>
<td class="paramname"><em>b</em> </td>
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<td>)</td>
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<p>Multiplies the affine transformations in a and b together and stores the result in this matrix. </p>
<p>The effect of the resulting transformation is to first apply the transformation in a to the coordinates and then apply the transformation in b to the coordinates.</p>
<p>It is allowable for result to be identical to either a or b.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">a</td><td>a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> </td></tr>
<tr><td class="paramname">b</td><td>a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a></td></tr>
</table>
</dd>
</dl>
<dl class="section see"><dt>See also</dt><dd><a class="el" href="classCairo_1_1Matrix.html#ab0bbb2ec9c1451f42f0270652df8cada" title="Multiplies the affine transformations in a and b together and returns the result. ...">operator*()</a> </dd></dl>
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<td class="memname">void Cairo::Matrix::rotate </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>radians</em></td><td>)</td>
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<p>Applies rotation by radians to the transformation in matrix. </p>
<p>The effect of the new transformation is to first rotate the coordinates by radians, then apply the original transformation to the coordinates.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">radians</td><td>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. </td></tr>
</table>
</dd>
</dl>
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<td class="memname">void Cairo::Matrix::scale </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>sx</em>, </td>
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<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>sy</em> </td>
</tr>
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<td></td>
<td>)</td>
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<p>Applies scaling by sx, sy to the transformation in matrix. </p>
<p>The effect of the new transformation is to first scale the coordinates by sx and sy, then apply the original transformation to the coordinates.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">sx</td><td>scale factor in the X direction </td></tr>
<tr><td class="paramname">sy</td><td>scale factor in the Y direction </td></tr>
</table>
</dd>
</dl>
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<td class="memname">void Cairo::Matrix::transform_distance </td>
<td>(</td>
<td class="paramtype">double & </td>
<td class="paramname"><em>dx</em>, </td>
</tr>
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<td class="paramkey"></td>
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<td class="paramtype">double & </td>
<td class="paramname"><em>dy</em> </td>
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<td>)</td>
<td></td><td> const</td>
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<p>Transforms the distance vector (dx,dy) by matrix. </p>
<p>This is similar to <a class="el" href="classCairo_1_1Matrix.html#af0b0ac8dd645036fdd4a3ee54cdcaca6" title="Transforms the point (x, y) by this matrix. ">transform_point()</a> except that the translation components of the transformation are ignored. The calculation of the returned vector is as follows:</p>
<div class="fragment"><div class="line">dx2 = dx1 * a + dy1 * c;</div>
<div class="line">dy2 = dx1 * b + dy1 * d;</div>
</div><!-- fragment --><p>Affine transformations are position invariant, so the same vector always transforms to the same vector. If (x1,y1) transforms to (x2,y2) then (x1+dx1,y1+dy1) will transform to (x1+dx2,y1+dy2) for all values of x1 and x2.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">dx</td><td>X component of a distance vector. An in/out parameter </td></tr>
<tr><td class="paramname">dy</td><td>Y component of a distance vector. An in/out parameter </td></tr>
</table>
</dd>
</dl>
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<td class="memname">void Cairo::Matrix::transform_point </td>
<td>(</td>
<td class="paramtype">double & </td>
<td class="paramname"><em>x</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">double & </td>
<td class="paramname"><em>y</em> </td>
</tr>
<tr>
<td></td>
<td>)</td>
<td></td><td> const</td>
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<p>Transforms the point (x, y) by this matrix. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">x</td><td>X position. An in/out parameter </td></tr>
<tr><td class="paramname">y</td><td>Y position. An in/out parameter </td></tr>
</table>
</dd>
</dl>
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<td class="memname">void Cairo::Matrix::translate </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>tx</em>, </td>
</tr>
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<td class="paramkey"></td>
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<td class="paramtype">double </td>
<td class="paramname"><em>ty</em> </td>
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<p>Applies a translation by tx, ty to the transformation in matrix. </p>
<p>The effect of the new transformation is to first translate the coordinates by tx and ty, then apply the original transformation to the coordinates.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">tx</td><td>amount to translate in the X direction </td></tr>
<tr><td class="paramname">ty</td><td>amount to translate in the Y direction </td></tr>
</table>
</dd>
</dl>
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<h2 class="groupheader">Friends And Related Function Documentation</h2>
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<td class="memname"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> identity_matrix </td>
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<p>Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to the identity matrix. </p>
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<td class="memname"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> operator* </td>
<td>(</td>
<td class="paramtype">const <a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& </td>
<td class="paramname"><em>a</em>, </td>
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<td class="paramtype">const <a class="el" href="classCairo_1_1Matrix.html">Matrix</a>& </td>
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<p>Multiplies the affine transformations in a and b together and returns the result. </p>
<p>The effect of the resulting transformation is to first apply the transformation in a to the coordinates and then apply the transformation in b to the coordinates.</p>
<p>It is allowable for result to be identical to either a or b.</p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">a</td><td>a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> </td></tr>
<tr><td class="paramname">b</td><td>a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> </td></tr>
</table>
</dd>
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<td class="memname"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> rotation_matrix </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>radians</em></td><td>)</td>
<td></td>
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<p>Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that rotates by radians. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">radians</td><td>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. </td></tr>
</table>
</dd>
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<td class="memname"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> scaling_matrix </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>sx</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>sy</em> </td>
</tr>
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<td>)</td>
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<p>Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that scales by sx and sy in the X and Y dimensions, respectively. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">sx</td><td>scale factor in the X direction </td></tr>
<tr><td class="paramname">sy</td><td>scale factor in the Y direction </td></tr>
</table>
</dd>
</dl>
</div>
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<td class="memname"><a class="el" href="classCairo_1_1Matrix.html">Matrix</a> translation_matrix </td>
<td>(</td>
<td class="paramtype">double </td>
<td class="paramname"><em>tx</em>, </td>
</tr>
<tr>
<td class="paramkey"></td>
<td></td>
<td class="paramtype">double </td>
<td class="paramname"><em>ty</em> </td>
</tr>
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<td></td>
<td>)</td>
<td></td><td></td>
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<p>Returns a <a class="el" href="classCairo_1_1Matrix.html" title="A Transformation matrix. ">Matrix</a> initialized to a transformation that translates by tx and ty in the X and Y dimensions, respectively. </p>
<dl class="params"><dt>Parameters</dt><dd>
<table class="params">
<tr><td class="paramname">tx</td><td>amount to translate in the X direction </td></tr>
<tr><td class="paramname">ty</td><td>amount to translate in the Y direction </td></tr>
</table>
</dd>
</dl>
</div>
</div>
<hr/>The documentation for this class was generated from the following file:<ul>
<li>cairomm/matrix.h</li>
</ul>
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