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<h6 id="header">RMagick 2.13.2 User's Guide and Reference</h6>
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<h1>class RVG::Pattern <span class="superclass"><
Object</span></h1>
<div id="toc">
<h2>Table of Contents</h2>
<h3>class methods</h3>
<ul>
<li><a href="#new">new</a></li>
</ul>
<h3>instance methods</h3>
<div>
<div class="toccol">
<ul>
<li><a href="#g">g</a></li>
<li><a href="#image">image</a></li>
<li><a href=
"#preserve_aspect_ratio">preserve_aspect_ratio</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#rvg">rvg</a></li>
<li><a href="#RVG_text">text</a></li>
</ul>
</div>
<div class="toccol">
<ul>
<li><a href="#RVG_use">use</a></li>
<li><a href="#viewbox">viewbox</a></li>
</ul>
</div>
</div>
<h3>shared methods</h3>
<p>In addition to the methods listed above, this class also
implements the <a href="rvgstyle.html">styles</a> method, the
<a href="rvgshape.html">shape methods</a> and the <a href=
"rvgxform.html">transform methods</a>.</p>
</div>
<h2 class="methods">class methods</h2>
<div class="sig">
<h3 id="new">new</h3>
<p>RVG::Pattern.new(<span class="arg">width</span>=0,
<span class="arg">height</span>=0, <span class=
"arg">x</span>=0, <span class="arg">y</span>=0) [ <span class=
"arg">{ |pattern| drawing method calls }</span> ] ->
<em>pattern</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Creates a pattern that can be used with the
<code>:fill</code> and <code>:stroke</code> styles.</p>
<p>Define the pattern in the associated block. The pattern can
be composed of <a href="rvgshape.html">shapes</a>, <a href=
"rvgtext.html#new">text</a>, <a href="rvgimage.html#new">raster
images</a>, <a href="rvggroup.html#new">groups</a>, and
<a href="rvg.html#RVG_new">RVG objects</a>. You can use the
<a href="rvguse.html#new">use</a> method to include graphic
objects in the pattern.</p>
<h4>Arguments</h4>
<dl>
<dt>width, height</dt>
<dd>These arguments define the pattern viewport.</dd>
<dt>x, y</dt>
<dd>Specify the starting offset of the pattern. The pattern
will be repeated at <span class=
"arg">x</span><code>+m*width</code> and <span class=
"arg">y</span><code>+n*height</code> offsets.</dd>
</dl>
<h4>Example</h4>
<p><a href="javascript:popup('rvg_pattern.rb.html')"><img src=
"ex/rvg_pattern.gif" title="Click to see the example script"
alt="pattern example" /></a></p>
</div>
<h2 class="methods">instance methods</h2>
<div class="sig">
<h3 id='g'>g</h3>
<p><span class="arg">pattern.</span>g [{|<span class=
"arg">grp</span>| ...}] -> <em>group</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Calls <a href="rvggroup.html#new">RVG::Group.new</a> to
construct a group and adds it to the pattern. Yields to a block
if one is present, passing the new group as an argument.</p>
<h4>Returns</h4>
<p>Returns the new group, so <code>RVG::Group</code> methods
can be chained to this method.</p>
</div>
<div class="sig">
<h3 id='image'>image</h3>
<p><span class="arg">pattern.</span>image(<span class=
"arg">raster_image</span>, <span class="arg">width</span>=nil,
<span class="arg">height</span>=nil, <span class=
"arg">x</span>=0, <span class="arg">y</span>=0) ->
<em>image</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Calls <a href="rvgimage.html#new">RVG::Image.new</a> to
construct an image and adds it to the pattern.</p>
<h4>Returns</h4>
<p>Returns the new image, so <code>RVG::Image</code> methods
can be chained to this method.</p>
</div>
<div class="sig">
<h3 id='preserve_aspect_ratio'>preserve_aspect_ratio</h3>
<p><span class=
"arg">pattern</span>.preserve_aspect_ratio(<span class=
"arg">align</span>, <span class=
"arg">meet_or_slice</span>='meet') [{|<span class=
"arg">self</span>| ...}] -> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>If you use the <a href="#viewbox">viewbox</a> method and the
user coordinate system does not scale uniformly to the default
coordinate system, use the <code>preserve_aspect_ratio</code>
method to specify whether or not the content is stretched to
fit. If not, you can specify how to fit the content into the
space.</p>
<p><code>Preserve_aspect_ratio</code> yields to a block if one
is present, passing <span class="arg">self</span> as an
argument.</p>
<h4>Arguments</h4>
<dl>
<dt>align</dt>
<dd>
When the value of the <code>meet_or_slice</code> argument
is 'meet' or 'slice', this argument controls the placement
of the content within the viewport. The <code>align</code>
argument is the concatenation of an <em>x</em>-alignment and
a <em>y</em>-alignment. The values are shown in these
lists:
<h6><em>x</em>-alignment</h6>
<dl>
<dt>xMin</dt>
<dd>align the minimum <em>x</em> value of the content
with the left corner of the viewport.</dd>
<dt>xMid</dt>
<dd>vertically center the content within the
viewport.</dd>
<dt>xMax</dt>
<dd>align the maximum <em>x</em> value of the content
with the right corner of the viewport.</dd>
</dl>
<h6><em>y</em>-alignment</h6>
<dl>
<dt>YMin</dt>
<dd>align the minimum <em>y</em> value of the content
with the top of the viewport.</dd>
<dt>YMid</dt>
<dd>horizontally center the content within the
viewport.</dd>
<dt>YMax</dt>
<dd>align the maximum <em>y</em> value of the content
with the bottom of the viewport</dd>
</dl>
</dd>
<dt>meet_or_slice</dt>
<dd>
This argument can have one of these three values:
<dl>
<dt>'none'</dt>
<dd>The content is scaled as necessary so that it fits
exactly within the viewport. The aspect ratio is
<em>not</em> maintained.</dd>
<dt>'meet'</dt>
<dd>The content is scaled as necessary so that the larger
dimension exactly fits the viewport. There may be some
unused space in the viewport. The aspect ratio is
maintained.</dd>
<dt>'slice'</dt>
<dd>The content is scaled as necessary so that the
smaller dimension exactly fits the viewport. Some of the
content in the larger dimension may be cut off. The
aspect ratio is maintained.</dd>
</dl>
</dd>
</dl>
<h4>Example</h4>
<p>See the RVG class <a href=
"rvg.html#RVG_preserve_aspect_ratio">example</a>.</p>
<h4>Returns</h4>
<p><span class="arg">Self</span>, so other
<code>RVG::Pattern</code> methods can be chained to this
method.</p>
<h4>See Also</h4>
<p><a href="#viewbox">viewbox</a></p>
</div>
<div class="sig">
<h3 id="rvg">rvg</h3>
<p><span class="arg">pattern</span>.rvg(<span class=
"arg">width</span>, <span class="arg">height</span>,
<span class="arg">x</span>=0, <span class="arg">y</span>=0)
[{|<span class="arg">new_rvg</span>| ...}] ->
<em>pattern</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>This method constructs a new RVG object and adds it to the
pattern. Each nested RVG object can use the <a href=
"rvg.html#RVG_viewbox">viewbox</a> method to define its own
coordinate system. The <code>rvg</code> method yields to a
block, passing the nested RVG object as an argument. Within the
block, any drawing objects added to the nested RVG object are
rendered within the nested RVG object's viewport.</p>
<h4>Arguments</h4>
<dl>
<dt>width, height</dt>
<dd>Specifies the viewport width and height. The units are in
the user coordinate system of the parent container.</dd>
<dt>x, y</dt>
<dd>The x- and y-axis offsets of the viewport upper-left
corner. The units are in the user coordinate system of the
parent container.</dd>
</dl>
<h4>Example</h4>
<p>See the example for <a href=
"#RVG_preserve_aspect_ratio">preserve_aspect_ratio</a> in
<code>class RVG</code>.</p>
<h4>Returns</h4>
<p>The <code>RVG</code> object, so other <code>RVG</code>
methods can be chained to this method.</p>
</div>
<div class="sig">
<h3 id='RVG_text'>text</h3>
<p><span class="arg">pattern.</span>text(<span class=
"arg">x</span>=0, <span class="arg">y</span>=0, <span class=
"arg">text</span>=nil) [{|<span class="arg">text</span>| ...}]
-> <em>text</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Calls <a href="rvgtext.html#new">RVG::Text.new</a> to
construct a text object and adds it to the pattern. Yields to a
block if one is present, passing the new text object as an
argument.</p>
<h4>Returns</h4>
<p>The <code>RVG::Text</code> object, so other
<code>RVG::Text</code> methods can be chained to this
method.</p>
</div>
<div class="sig">
<h3 id="RVG_use">use</h3>
<p><span class="arg">pattern</span>.use(<span class=
"arg">obj</span>, <span class="arg">x</span>=0, <span class=
"arg">y</span>=0, <span class="arg">width</span>=nil,
<span class="arg">height</span>=nil) -> <em>use</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>Calls <a href="rvguse.html#new">RVG::Use.new</a> to
constructs a <code>use</code> object and adds it to the
pattern.</p>
<p>When the referenced argument is an RVG object, <span class=
"arg">width</span> and <span class="arg">height</span> can be
used to specify the width and height of the viewport. If
present and non-nil, these arguments override any width and
height specified when the RVG object was created. You must
specify the viewport size either when creating the RVG object
or when referencing it with <code>use</code>.</p>
<h4>Examples</h4>
<p>See <a href="rvguse.html#new">RVG::Use.new</a></p>
<h4>Returns</h4>
<p>The <code>RVG::Use</code> object, so other
<code>RVG::Use</code> methods can be chained to this
method.</p>
</div>
<div class="sig">
<h3 id="viewbox">viewbox</h3>
<p><span class="arg">pattern</span>.viewbox(<span class=
"arg">min_x</span>, <span class="arg">min_y</span>,
<span class="arg">width</span>, <span class=
"arg">height</span>) [{|<span class="arg">self</span>| ...}]
-> <em>self</em></p>
</div>
<div class="desc">
<h4>Description</h4>
<p>The area of the pattern is called the <em>viewport</em>. By
default the origin of the coordinate system for an pattern is
(0,0). The user coordinates are pixels and the width and height
are established by the <span class="arg">width</span> and
<span class="arg">height</span> arguments to
<code>RVG::Pattern.new</code>.</p>
<p>Use the <code>viewbox</code> method to superimpose a user
coordinate system on the viewport. The <code>viewbox</code>
method lets you set up a coordinate system using the units of
your choice.</p>
<p>The <code>viewbox</code> method yields to a block if one is
present, passing <code>self</code> as an argument.</p>
<h4>Arguments</h4>
<dl>
<dt>min_x, min_y</dt>
<dd>The minimum <em>x</em>-coordinate and
<em>y</em>-coordinate of the user coordinate system.</dd>
<dt>width, height</dt>
<dd>The width and height of the user coordinate system.</dd>
</dl>
<h4>Example</h4>
<p>See the <a href="rvg.html#RVG_viewbox">example</a> for the
<code>RVG</code> class.</p>
<h4>Returns</h4>
<p><span class="arg">Self</span>, so other
<code>RVG::Pattern</code> methods may be chained to
<code>viewbox</code>.</p>
<h4>See Also</h4>
<p><a href=
"#preserve_aspect_ratio">preserve_aspect_ratio</a></p>
</div>
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