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<?xml version="1.0" encoding="UTF-8" standalone="no"?> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <title>2. Selection Tools</title> <link rel="stylesheet" href="gimp-help-plain.css" type="text/css" /> <link rel="stylesheet" href="gimp-help-screen.css" type="text/css" /> <link rel="stylesheet" href="gimp-help-custom.css" type="text/css" /> <link rel="alternate stylesheet" href="gimp22.css" type="text/css" title="gimp22" /> <meta name="generator" content="DocBook XSL Stylesheets V1.73.2" /> <link rel="start" href="index.html" title="GNU Image Manipulation Program" /> <link rel="up" href="gimp-toolbox.html" title="Chapter 13.  Toolbox" /> <link rel="prev" href="gimp-toolbox.html" title="Chapter 13.  Toolbox" /> <link rel="next" href="gimp-tool-rect-select.html" title="2.2.  Rectangle Selection" /> </head> <body> <div class="navheader"> <table width="100%" summary="Navigation header"> <tr> <th colspan="3" align="center">2. Selection Tools</th> </tr> <tr> <td width="20%" align="left"><a accesskey="p" href="gimp-toolbox.html"><img src="../images/prev.png" alt="Prev" /></a> </td> <th width="60%" align="center">Chapter 13.  <span lang="en" xml:lang="en">Toolbox</span> </th> <td width="20%" align="right"> <a accesskey="n" href="gimp-tool-rect-select.html"><img src="../images/next.png" alt="Next" /></a></td> </tr> </table> <hr /> </div> <div class="sect1" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h2 class="title" style="clear: both"><a id="gimp-tools-selection"></a>2. Selection Tools</h2> </div> </div> </div> <div class="sect2" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h3 class="title"><a id="gimp-tool-select"></a>2.1.  <span lang="en" xml:lang="en">Common Features</span> </h3> </div> <div> <div class="revhistory"> <table border="1" width="100%" summary="Revision history"> <tr> <th align="left" valign="top" colspan="3"> <b>Revision History</b> </th> </tr> <tr> <td align="left">Revision $Revision: 2429 $</td> <td align="left">2006-06-15</td> <td align="left">j.h</td> </tr> </table> </div> </div> </div> </div> <a id="id2621046" class="indexterm"></a> <div class="figure"> <a id="id2621060"></a> <p class="title"> <b>Figure 13.2.  <span lang="en" xml:lang="en">The Selection tools</span> </b> </p> <div class="figure-contents"> <div class="mediaobject"> <img src="../images/toolbox/selection-tools.png" alt="The Selection tools" /> </div> </div> </div> <br class="figure-break" /> <p> Selection tools are designed to select regions from images or layers so you can work on them without affecting the unselected areas. Each tool has its own individual properties, but the selection tools also share a number of options and features in common. These common features are described here; the variations are explained in the following sections for each tool specifically. If you need help with what a “<span class="quote">selection</span>” is in GIMP, and how it works, see <a class="link" href="gimp-painting.html#gimp-concepts-selection" title="1.  The Selection">Selection</a>. </p> <p>There are seven selection tools:</p> <div class="itemizedlist"> <ul type="disc"> <li> <p> the <a class="link" href="gimp-tool-rect-select.html" title="2.2.  Rectangle Selection">Rectangle Select</a>; </p> </li> <li> <p> the <a class="link" href="gimp-tool-ellipse-select.html" title="2.3.  Ellipse Selection">Ellipse Select</a>; </p> </li> <li> <p> the <a class="link" href="gimp-tool-free-select.html" title="2.4.  Free Selection (Lasso)">Free Select (the Lasso)</a>; </p> </li> <li> <p> the <a class="link" href="gimp-tool-fuzzy-select.html" title="2.5.  Fuzzy selection (Magic wand)"> Select Contiguous Regions (the Magic Wand) </a>; </p> </li> <li> <p> the <a class="link" href="gimp-tool-by-color-select.html" title="2.6.  Select By Color">Select by Color</a>; </p> </li> <li> <p> the <a class="link" href="gimp-tool-iscissors.html" title="2.7.  Scissors"> Select Shapes from Image (Intelligent Scissors) </a> and </p> </li> <li> <p> the <a class="link" href="gimp-tool-foreground-select.html" title="2.8.  Foreground Select">Foreground Select</a>. </p> </li> </ul> </div> <p> In some ways the Path tool can also be thought of as a selection tool: any closed path can be converted into a selection. It also can do a great deal more, though, and does not share the same set of options with the other selection tools. </p> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="gimp-tools-select-modifiers"></a>2.1.1.  <span lang="en" xml:lang="en">Key modifiers (Defaults)</span> </h4> </div> </div> </div> <p> The behavior of selection tools is modified if you hold down the <span class="keycap"><strong>Ctrl</strong></span>, <span class="keycap"><strong>Shift</strong></span>, and/or <span class="keycap"><strong>Alt</strong></span> keys while you use them. </p> <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="Note"> <tr> <td rowspan="2" align="center" valign="top" width="25"> <img alt="[Note]" src="../images/note.png" /> </td> <th align="left">Note</th> </tr> <tr> <td align="left" valign="top"> <p> Advanced users find the modifier keys very valuable, but novice users often find them confusing. Fortunately, it is possible for most purposes to use the Mode buttons (described below) instead of modifier keys. </p> </td> </tr> </table> </div> <div class="variablelist"> <dl> <dt> <span class="term"> <span class="keycap"> <strong>Ctrl</strong> </span> </span> </dt> <dd> <p> When creating a selection, holding down the <span class="keycap"><strong>Ctrl</strong></span> key can have two different actions according to the way you use it: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p> Holding down the key <span class="emphasis"><em>while drawing</em></span> the selection toggles the “<span class="quote">Expand from center</span>” option. </p> </li> <li> <p> If you hold down the <span class="keycap"><strong>Ctrl</strong></span> key <span class="emphasis"><em>before drawing a selection</em></span>, this new selection switches to the Subtract mode. So, this new selection will be subtracted from an existing one as soon as you release the click, as far as they have common pixels. </p> </li> </ul> </div> </dd> <dt> <span class="term"> <span class="keycap"> <strong>Alt</strong> </span> </span> </dt> <dd> <p> Holding <span class="keycap"><strong>Alt</strong></span> will allow movement of the current selection (only its frame, not its content). If the whole image is moved instead of the selection only, try <span class="keycap"><strong>Shift</strong></span>+<span class="keycap"><strong>Alt</strong></span>. Note that the <span class="keycap"><strong>Alt</strong></span> key is sometimes intercepted by the windowing system (meaning that GIMP never knows that it was pressed), so this may not work for everybody. </p> </dd> <dt> <span class="term"> <span class="keycap"> <strong>Shift</strong> </span> </span> </dt> <dd> <p> When creating a selection, holding down the <span class="keycap"><strong>Shift</strong></span> key can have two different actions according to the way you use it: </p> <div class="itemizedlist"> <ul type="disc"> <li> <p> If you hold down the key <span class="emphasis"><em>before clicking</em></span> to start the selection, this selection will be in <span class="emphasis"><em>Addition</em></span> mode as long as you press the key. </p> </li> <li> <p> If you hold down the <span class="keycap"><strong>Shift</strong></span> key <span class="emphasis"><em>after clicking</em></span> to start the selection, the effect will depend on the tool you are using: for example, the selection will be a square with the Rectangle Select tool. </p> </li> </ul> </div> </dd> <dt> <span class="term"> <span class="keycap"><strong>Ctrl</strong></span>+<span class="keycap"><strong>Shift</strong></span> </span> </dt> <dd> <p> Using <span class="keycap"><strong>Ctrl</strong></span>+<span class="keycap"><strong>Shift</strong></span> together can do a variety of things, depending on which tool is used. Common to all selection tools is that the selection mode will be switched to intersection, so that after the operation is finished, the selection will consist of the intersection of the region traced out with the pre-existing selection. It is an exercise for the reader to play with the various combinations available when performing selections while holding <span class="keycap"><strong>Ctrl</strong></span>+<span class="keycap"><strong>Shift</strong></span> and releasing either both or either prior to releasing the <span class="mousebutton">mouse button</span>. </p> </dd> <dt> <span class="term">Key modifiers to move selections</span> </dt> <dd> <p> <span class="keycap"><strong>Ctrl</strong></span>+<span class="keycap"><strong>Alt</strong></span>+<span class="keycap"><strong>Click-and-drag</strong></span> and <span class="keycap"><strong>Shift</strong></span>+<span class="keycap"><strong>Alt</strong></span>+<span class="keycap"><strong>Click-and-drag</strong></span> are used to move selections. See <a class="link" href="gimp-using-selections.html#gimp-using-selections-moving" title="2.1.  Moving a Selection">Moving selections</a> </p> </dd> <dt> <span class="term">Space bar</span> </dt> <dd> <p> Pressing the <span class="keycap"><strong>Space Bar</strong></span> while using a selection tool transforms this tool into Move tool as long as you press the bar. If you want to move the selection with this method, you must set the icon of the option <span class="guiicon"> <span class="inlinemediaobject"><img src="../images/toolbox/tool-options-move-selection.png" /></span> </span>. </p> </dd> </dl> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="gimp-tool-select-options"></a>2.1.2.  <span lang="en" xml:lang="en">Options</span> </h4> </div> </div> </div> <p> Here we describe the tool options that apply to all selection tools: options that apply only to some tools, or that affect each tool differently, are described in the sections devoted to the individual tools. The current settings for these options can be seen in the Tool Options dialog, which you should always have visible when you are using tools. (Most users keep it docked directly below the Toolbox.) To make the interface consistent, the same options are presented for all selection tools, even though some of them don't have any effect for some of the tools. </p> <div class="figure"> <a id="id2621738"></a> <p class="title"> <b>Figure 13.3.  <span lang="en" xml:lang="en">Common options of selection tools</span> </b> </p> <div class="figure-contents"> <div class="mediaobject"> <img src="../images/toolbox/tool-options-selection.png" alt="Common options of selection tools" /> </div> </div> </div> <br class="figure-break" /> <div class="variablelist"> <dl> <dt> <span class="term">Mode</span> </dt> <dd> <a id="id2621781" class="indexterm"></a> <p> This determines the way that the selection you create is combined with any pre-existing selection. Note that the functions performed by these buttons can be duplicated using modifier keys, as described above. For the most part, advanced users use the modifier keys; novice users find the mode buttons easier. </p> <div class="variablelist"> <dl> <dt> <span class="term"> <span class="inlinemediaobject"><img src="../images/tool-options/rectsel-mode-replace.png" /></span> </span> </dt> <dd> <p> Replace mode will cause any existing selection to be destroyed or replaced when the new selection is created. </p> </dd> <dt> <span class="term"> <span class="inlinemediaobject"><img src="../images/tool-options/rectsel-mode-add.png" /></span> </span> </dt> <dd> <p> Add mode will cause the new selection to be added to any existing selection regions. </p> </dd> <dt> <span class="term"> <span class="inlinemediaobject"><img src="../images/tool-options/rectsel-mode-subtract.png" /></span> </span> </dt> <dd> <p> Subtract mode will remove the new selection area from any existing selection regions. </p> </dd> <dt> <span class="term"> <span class="inlinemediaobject"><img src="../images/tool-options/rectsel-mode-intersect.png" /></span> </span> </dt> <dd> <p> Intersection mode will make a new selection from the area where the existing selection region and the new selection region overlap. </p> </dd> </dl> </div> </dd> <dt> <span class="term">Antialiasing</span> </dt> <dd> <p> This option only affects a few of the selection tools: it causes the boundary of the selection to be drawn more smoothly. </p> </dd> <dt> <span class="term">Feather Edges</span> </dt> <dd> <a id="id2621966" class="indexterm"></a> <p> This options allows the boundary of the selection to be blurred, so that points near the boundary are only partially selected. For further information regarding feathering, see the glossary entry <a class="link" href="glossary.html#glossary-feathering" title="Feathering">Feathering</a>. </p> </dd> </dl> </div> </div> <div class="sect3" lang="en" xml:lang="en"> <div class="titlepage"> <div> <div> <h4 class="title"><a id="id2622000"></a>2.1.3.  <span lang="en" xml:lang="en">Additional information</span> </h4> </div> </div> </div> <div class="note" style="margin-left: 0.5in; margin-right: 0.5in;"> <table border="0" summary="Note"> <tr> <td rowspan="2" align="center" valign="top" width="25"> <img alt="[Note]" src="../images/note.png" /> </td> <th align="left">Note</th> </tr> <tr> <td align="left" valign="top"> <p> When moving a selection beyond the boundaries of the image canvas, the selection will be cropped to the image area. Selections can exist on the visible canvas only. Selection movements and changes are, however, kept in the undo buffer should you need to repair an error. </p> </td> </tr> </table> </div> </div> </div> </div> <div class="navfooter"> <hr /> <table width="100%" summary="Navigation footer"> <tr> <td width="40%" align="left"><a accesskey="p" href="gimp-toolbox.html"><img src="../images/prev.png" alt="Prev" /></a> </td> <td width="20%" align="center"> <a accesskey="u" href="gimp-toolbox.html"> <img src="../images/up.png" alt="Up" /> </a> </td> <td width="40%" align="right"> <a accesskey="n" href="gimp-tool-rect-select.html"><img src="../images/next.png" alt="Next" /></a></td> </tr> <tr> <td width="40%" align="left" valign="top"><a accesskey="p" href="gimp-toolbox.html">Chapter 13.  <span lang="en" xml:lang="en">Toolbox</span> </a> </td> <td width="20%" align="center"> <a accesskey="h" href="index.html"> <img src="../images/home.png" alt="Home" /> </a> </td> <td width="40%" align="right" valign="top"> <a accesskey="n" href="gimp-tool-rect-select.html">2.2.  <span lang="en" xml:lang="en">Rectangle Selection</span> </a></td> </tr> </table> </div> </body> </html> 
