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    <title>RMagick 6.1.1: RVG Reference: Styles</title>
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    <h6 id="header">RMagick 6.1.1 User's Guide and Reference</h6>

    <div class="nav">&laquo;&nbsp;<a href="rvguse.html">Prev</a> | <a href="index.html">Contents</a> | <a href="rvgshape.html">Next</a>&nbsp;&raquo;</div>

    <h1>The styles method</h1>

    <div id="toc">
      <h2>Table of Contents</h2>

      <h3>instance methods</h3>

      <div>
        <ul>
          <li><a href="#styles">styles</a></li>
        </ul>
      </div>
    </div>

    <h2 class="methods">styles</h2>

    <div class="sig">
      <h3 id="styles">styles</h3>

      <p>
        <span class="arg">obj.</span>styles(<span class="arg">:style=&gt;value</span>[, <span class="arg">:style=&gt;value</span>...]) [{|obj| }] -&gt;
        <em>obj</em>
      </p>
    </div>

    <div class="desc">
      <h4>Description</h4>

      <p>
        Assigns <em>styles</em> to the target object, which may be a container, shape, text, raster image, or pattern. Styles are presentational attributes that
        define how the object is rendered.
      </p>

      <p>
        <code>Styles</code> yields to a block if a block is present, passing the target object as an argument. This is useful when <code>styles</code> is
        chained to a container constructor method such as <a href="rvg.html#RVG_g">g</a> or <a href="rvg.html#RVG_rvg">rvg</a>. By default, objects within a
        container get the styles defined on the container.
      </p>

      <p><code>Styles</code> returns the target object, so other methods can be chained to it.</p>

      <h4>Arguments</h4>

      <p>The argument is a hash. The hash keys are style name symbols. The hash values are the style values. RVG supports the following style names.</p>

      <dl>
        <dt>:clip_path</dt>

        <dd>An outline used to clip a shape or collection of shapes. The value is an <a href="rvgclip.html#new">clipping path</a>.</dd>

        <dt>:clip_rule</dt>

        <dd>
          If the <code>clip_path</code> style is used, how to determine if a point is inside or outside a the clip path. The value is a string, either 'nonzero'
          or 'evenodd'. The default is 'nonzero'. See the <code>fill_rule</code> example below.
        </dd>

        <dt>:fill</dt>

        <dd>
          The fill color. The value must be a
          <a href="imusage.html#color_names">color name</a> or a <a href="rvgpattern.html#new">pattern</a>. The default is 'black'.
        </dd>

        <dt>:fill_opacity</dt>

        <dd>The opacity of the fill color. A number between 0.0 (fully transparent) and 1.0 (fully opaque). The default is 1.0</dd>

        <dt>:fill_rule</dt>

        <dd>How to determine if a point is inside or outside a shape. The value is a string, either 'nonzero' or 'evenodd'. The default is 'nonzero'.</dd>

        <dd>
          The following descriptions of 'nonzero' and 'evenodd' are from the
          <a href="https://www.w3.org/TR/SVG11/painting.html#FillProperties">SVG 1.1 standard</a>.

          <dl>
            <dt>nonzero</dt>

            <dd>
              This rule determines the "insideness" of a point on the canvas by drawing a ray from that point to infinity in any direction and then examining
              the places where a segment of the shape crosses the ray. Starting with a count of zero, add one each time a path segment crosses the ray from left
              to right and subtract one each time a path segment crosses the ray from right to left. After counting the crossings, if the result is zero then
              the point is outside the path. Otherwise, it is inside.
            </dd>

            <dt>evenodd</dt>

            <dd>
              This rule determines the "insideness" of a point on the canvas by drawing a ray from that point to infinity in any direction and counting the
              number of path segments from the given shape that the ray crosses. If this number is odd, the point is inside; if even, the point is outside.
            </dd>
          </dl>
        </dd>

        <dd>See the examples below.</dd>

        <dt>:opacity</dt>

        <dd>
          Both the stroke and the fill opacity. A number between 0.0 (fully transparent) and 1.0 (fully opaque). The default is 1.0. See below for an example.
        </dd>

        <dt>:stroke</dt>

        <dd>
          The stroke color. The value must be a
          <a href="imusage.html#color_names">color name</a> or a <a href="rvgpattern.html#new">pattern</a>. The default is 'none', that is, transparent black
          ("#000000ff").
        </dd>

        <dt>:stroke_dasharray</dt>

        <dd>
          An array of numbers that specify the length of the dashes and gaps with which to draw a dashed line. If the array contains an odd number of values,
          the values are repeated to produce an even number of dashes and gaps. The numbers are in user coordinates. By default all lines are drawn as solid
          lines. See below for an example.
        </dd>

        <dt>:stroke_dashoffset</dt>

        <dd>
          Normally a dashed line is drawn using the first number in the stroke_dasharray as the length of the first dash. This style can be used to specify a
          different starting point in the array.
        </dd>

        <dt>:stroke_linecap</dt>

        <dd>
          The shape of the end of a line. The value may be one of the strings 'butt', 'round', or 'square'. The default is 'butt'. See below for an example.
        </dd>

        <dt>:stroke_linejoin</dt>

        <dd>
          The shape of the corner where two lines are joined. The value may be one of the strings 'miter', 'round', or 'bevel'. The default is 'miter'. See
          below for an example.
        </dd>

        <dt>:stroke_miterlimit</dt>

        <dd>
          If the <code>stroke_linejoin</code> value is 'miter', a number specifying the ratio of the miter to the thickness of the lines being joined. When the
          limit is exceeded the join is converted from a miter to a bevel. The value must be a number greater than or equal to 1.0. The default is 4.0.
        </dd>

        <dt>:stroke_opacity</dt>

        <dd>
          The opacity of the stroke color. A number between 0.0 (fully transparent) and 1.0 (fully opaque). The default is 1.0 unless
          <code>stroke</code> has the default value 'none'.
        </dd>

        <dt>:stroke_width</dt>

        <dd>The thickness of the stroke. The default is 1 user coordinate.</dd>
      </dl>

      <p>
        (Text styles are described with the
        <a href="rvgtext.html#new">Text</a> class.)
      </p>

      <h4>Examples</h4>

      <p>
        <strong>:fill=&gt;'#00ff00', :stroke=&gt;'blue', :stroke_width=&gt;8</strong
        ><a href="javascript:popup('stroke_fill.rb.html')"
          ><img src="ex/stroke_fill.gif" title="Click to see the example script" alt="stroke and fill example"
        /></a>
      </p>

      <p>
        <strong>:fill_rule=&gt;'nonzero'</strong
        ><a href="javascript:popup('nonzero.rb.html')"><img src="ex/nonzero.gif" title="Click to see the example script" alt="nonzero example" /></a>
      </p>

      <p>
        <strong>:fill_rule=&gt;'evenodd'</strong
        ><a href="javascript:popup('evenodd.rb.html')"><img src="ex/evenodd.gif" title="Click to see the example script" alt="evenodd example" /></a>
      </p>

      <p>
        <strong>Three values of :opacity</strong
        ><a href="javascript:popup('rvg_opacity.rb.html')"><img src="ex/rvg_opacity.gif" title="Click to see the example script" alt="opacity example" /></a>
      </p>

      <p>
        <strong>:stroke_dasharray=&gt;[10,5]</strong
        ><a href="javascript:popup('rvg_stroke_dasharray.rb.html')"
          ><img src="ex/rvg_stroke_dasharray.gif" title="Click to see the example script" alt="stroke_dasharray example"
        /></a>
      </p>

      <p>
        <strong>Three values of :stroke_linecap</strong
        ><a href="javascript:popup('rvg_linecap.rb.html')"
          ><img src="ex/rvg_linecap.gif" title="Click to see the example script" alt="stroke_linecap example"
        /></a>
      </p>

      <p>
        <strong>Three values of :stroke_linejoin</strong
        ><a href="javascript:popup('rvg_linejoin.rb.html')"
          ><img src="ex/rvg_linejoin.gif" title="Click to see the example script" alt="stroke_linejoin example"
        /></a>
      </p>

      <h4>Returns</h4>

      <p><span class="arg">obj</span></p>
    </div>

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