csswg-drafts/css-shapes/split/notes at 2746c011ac439df0b22b2113a693c8534212d3d7 · w3c/csswg-drafts · GitHub

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the <span>exclusion area</span> for an <span>exclusion element</span>
        or
(cut from Shapes section intro)


        <span>exclusions</span> and
(cut from Shapes section intro note)


    <dfn>Content area</dfn>
    <p>
        The <a href="http://www.w3.org/TR/CSS2/box.html#box-dimensions">content area</a>
        is normally used for layout of the inline flow content of a box.
    </p>

    <div class="issue-marker" data-bug_id="15089" data-bug_status="NEW">
      <a href="https://www.w3.org/Bugs/Public/show_bug.cgi?id=15089">Issue-15089</a>
      <div class="issue-details">
          <p class="short-desc">shrink-to-fit circle / shape</p>
      </div>
    </div>

    <dfn title="outside-inside">Outside and inside</dfn>

    <p>
        In this specification, 'outside' refers to DOM content that is not a descendant of an element
        while 'inside' refers to the element's descendants.
    </p>
(cut from shapes definitions)


        The inside shape defines an element's <span>content shape</span> and the element's inline
        content will flow within that shape.

            <p class="note">It is important to note that while outside shapes only apply to floats, inside shapes apply to all block-level elements.</p>
(cut from shapes intro)


    <div class="example">
        <p>
            CSS 'shape-outside' and CSS box model relation:
            the red box illustrates the exclusion element's
            content box, which is unmodified and subject to normal CSS positioning (here absolute positioning).</p>
<pre><code class="html">
&lt;style type="text/css"&gt;
    .exclusion  {
        wrap-flow: both;
        position: absolute;
        top: 25%;
        left: 25%;
        width: 50%;
        height: 50%;
        shape-outside: circle(50%, 50%, 50%);
        border: 1px solid red;
    }
&lt;/style&gt;

&lt;div style=”position: relative;”&gt;
    &lt;div class=”exclusion”&gt;&lt;/div&gt;
    Lorem ipsum dolor sit amet...
&lt;/div&gt;
</code></pre>
        <img class="singleImgExample" src="images/shapes_CSS2.1_MBP.png" alt="Example rendering of circle shape and box model."  style="max-width:40%"/>
    </div>
(cut exclusion example from shapes intro)


      <p class="note">
          Note, images can define cavities and inline flow content should wrap inside
          them. In order to avoid that, another exclusion element can be overlaid.
      </p>
(cut from Shapes from Image)

      <p>
          The shape defined by the 'shape-inside'
          and 'shape-padding' properties
          defines an <span>exclusion area</span>
          that contributes
          to the element's <span>wrapping context</span>.
          The
10BC0
 'shape-inside' property applies
          to all block-level elements.
      </p>
(cut from Declaring Shapes, along with shape-inside references)

The shape is computed
            based on the border box of the element for exclusions,
            or computed based on the margin box for floats.
(cut from shape-outside:auto definition)


      <div class='figure'>
          <img alt="arbitrary shapes for exclusions. Illustrates how content flows around shapes" src="images/shapes-exclusions.png" width="70%"/>
          <p class="caption">Arbitrary shapes for exclusions</p>
      </div>

      <div>
          <p>The above figure shows how
            'shape-outside' shapes
            impact the <span>exclusion areas</span>.
            The red box represents an element's content box
            and 'A', 'B', 'C' and 'C' represent exclusions
            with a complex shape
            and their 'wrap-flow' property
            computes to 'both', 'start', 'end' and 'clear',
            respectively.</p>

          <p>As illustrated in the picture,
            when an exclusion allows wrapping
            on all sides,
            text can flow inside 'holes'
            in the exclusion
            (as for exclusion 'A').
            Otherwise, the exclusion clears
            the area on the side(s)
            defined by 'wrap-flow',
            as illustrated
            for 'B', 'C' and 'D' above.</p>
      </div>
(cut from shape-outside)

      <h4 id="shape-inside-property">The 'shape-inside' Property</h4>
      <p>
          The 'shape-inside' property adds
          one or more exclusion areas
          to the element's wrapping context.
          This modifies the normal rectangular shape
          of the content area
          to a possibly non-rectangular wrapping area.
          The exclusion areas
          are defined by subtracting the shape
          from the element's content area.
          Any part of the shape outside
          the element's content area
          has no effect.
      </p>

      <table class="propdef">
          <tr>
              <th>Name:</th>
              <td><dfn title="'shape-inside'">shape-inside</dfn></td>
          </tr>
          <tr>
              <th>Value:</th>
              <td><var>outside-shape</var> | <var>auto</var> | <var>&lt;basic-shape&gt;</var> | <var>&lt;uri&gt;</var></td>
          </tr>
          <tr>
              <th>Initial:</th>
              <td>outside-shape</td>
          </tr>
          <tr>
              <th>Applies to:</th>
              <td>block-level elements</td>
          </tr>
          <tr>
              <th>Inherited:</th>
              <td>no</td>
          </tr>
          <tr>
              <th>Percentages:</th>
              <td>N/A</td>
          </tr>
          <tr>
              <th>Media:</th>
              <td>visual</td>
          </tr>
          <tr>
              <th>Computed&nbsp;value:</th>
              <td>computed lengths for &lt;basic-shape&gt;, the absolute URI for &lt;uri&gt;, otherwise as specified</td>
          </tr>
      </table>

    <p>The values of this property have the following meanings:</p>
    <dl>
        <dt><dfn title="'shape-inside'!!'outside-shape'">outside-shape</dfn></dt>
        <dd>
            The shape is computed
            based on the computed value
            of the 'shape-outside' property.
            E.g., when shape-outside
            computes to 'auto',
            use the meaning of 'auto' below
            to compute the shape.
        </dd>
    </dl>
    <dl>
        <dt><dfn title="'shape-inside'!!'auto'">auto</dfn></dt>
        <dd>
            The shape is computed based on the content box of the element.
        </dd>
    </dl>
    <dl>
        <dt><dfn title="'shape-inside'!!'&lt;basic-shape&gt;'">&lt;basic-shape&gt;</dfn></dt>
        <dd>
            The shape is computed based on the values of one of 'rectangle', 'inset-rectangle', 'circle', 'ellipse'
            or 'polygon'.
        </dd>
    </dl>
    <dl>
        <dt><dfn title="'shape-inside'!!'&lt;uri&gt;'">&lt;uri&gt;</dfn></dt>
        <dd>
            If the &lt;uri&gt; references an SVG shape element, that element defines the shape.
              Otherwise, if the &lt;uri&gt; references an image, the shape is extracted and computed
              based on the alpha channel of the specified image.

              If the &lt;uri&gt; does not reference an SVG shape element or an image, the
              effect is as if the value 'auto' had been specified.
        </dd>
    </dl>

    <p>The 'shape-inside' property applies to floats.</p>

    <p>The 'shape-inside' property may not apply on some elements such as elements with a
        computed 'display' value of 'table'.</p>

    <div class='figure'>
        <img alt="Content flowing with and without a shape-inside" src="images/shape-inside-content.png"/>
        <p class="caption">Effect of shape-inside on inline content.</p>
    </div>

    <p>Overflow content avoids
        the exclusion area(s) added
        by 'shape-inside' and 'shape-padding'
        (as well as any other exclusion areas
        in the element's wrapping context).</p>

    <div class='figure'>
            <img alt="Overflow interacting with rounded rect" style="display:inline-block;vertical-align:top" src="images/rounded-rect-overflow.png"/>
            <img alt="Overflow interacting with ellipse" style="display:inline-block;vertical-align:top" src="images/ellipse-overflow.png"/>
        <p class="caption">Overflow interacting with exclusion areas defined by 'shape-inside' and 'shape-padding'.</p>
    </div>

    <!-- End section "The shape-inside property" -->

  The 'shape-image-threshold'
        applies to both 'shape-outside' and 'shape-inside'.
(cut from shape-image-threshold)


    <h4 id="shape-padding-property">The 'shape-padding' Property</h4>
    <p>
        The 'shape-padding' property adds padding to a shape-inside.
        This defines a new shape where every point
        is the specified distance from the shape-inside.
        This property takes on positive values only.
    </p>
    <table class="propdef">
        <tr>
            <th>Name:</th>
            <td><dfn title="'shape-padding'">shape-padding</dfn></td>
        </tr>
        <tr>
            <th>Value:</th>
            <td><var>&lt;length&gt;</var></td>
        </tr>
        <tr>
            <th>Initial:</th>
            <td>0</td>
        </tr>
        <tr>
            <th>Applies to:</th>
            <td>block-level elements</td>
        </tr>
        <tr>
            <th>Inherited:</th>
            <td>no</td>
        </tr>
        <tr>
            <th>Percentages:</th>
            <td>N/A</td>
        </tr>
        <tr>
            <th>Media:</th>
            <td>visual</td>
        </tr>
        <tr>
            <th>Computed&nbsp;value:</th>
            <td>the absolute length</td>
        </tr>
    </table>

    <div class="example">
        <p>A 'shape-padding' creating an offset
            from a circlular shape-inside.
            The light blue rectangles represent
            inline content affected
            by the shape created
            by the padding.</p>
        <img src="images/shape-padding.png"
            alt="Example of a shape-padding offset"/>
    </div>
    <!-- End section "shape-padding property" -->

    <div class="note">Note that the 'shape-padding' property only affects layout of content inside
        the element it applies to while the 'shape-margin' property only affects layout of content
        outside the element.</div>