1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
|
<?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>2.3. Ellipse Selection Tool</title>
<link rel="stylesheet" href="gimp-help-plain.css" type="text/css" />
<link rel="stylesheet" href="gimp-help-screen.css" type="text/css" />
<meta name="generator" content="DocBook XSL Stylesheets V1.66.1" />
<link rel="start" href="index.html" title=" " />
<link rel="up" href="ch03s02.html" title="2. Selection Tools" />
<link rel="prev" href="ch03s02s02.html" title="2.2. Rectangle Selection Tool" />
<link rel="next" href="ch03s02s04.html" title="2.4. Free Selection Tool (Lasso)" />
</head>
<body>
<div xmlns="" class="navheader">
<table width="100%" summary="Navigation header">
<tr>
<th colspan="3" align="center" id="chaptername">2.3. Ellipse Selection Tool</th>
</tr>
<tr>
<td width="20%" align="left"><a accesskey="p" href="ch03s02s02.html">Prev</a> </td>
<th width="60%" align="center" id="sectionname">2.3. Ellipse Selection Tool</th>
<td width="20%" align="right"> <a accesskey="n" href="ch03s02s04.html">Next</a></td>
</tr>
</table>
<hr />
</div>
<div class="sect2" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h3 class="title"><a id="gimp-tool-ellipse-select"></a>2.3. Ellipse Selection Tool</h3>
</div>
</div>
</div>
<a id="id3316210" class="indexterm"></a>
<div class="informalfigure">
<div class="mediaobject">
<img src="../images/toolbox/toolbox-ellipsel.png" />
<div class="caption">
<p>
Ellipse Select icon in the Toolbox
</p>
</div>
</div>
</div>
<p>
The Ellipse Selection tool is designed to select circular and
elliptical regions from an image, with high-quality anti-aliasing
if you want it. For information on selections and how
they are used in GIMP see <a href="ch02s04s04.html" title="4.4. The Selection">Selections</a>; for information on
features common to all selection tools see <a href="ch03s02.html#gimp-tool-select" title="2.1. Common Features">Selection Tools</a>.
</p>
<p>
This tool is also used for rendering a circle or ellipse on an
image. To render a filled ellipse, create an elliptical
selection, and then fill it using the <a href="ch03s06s02.html" title="6.2. Bucket Fill">Bucket Fill tool</a>. To
create an elliptical outline, the simplest and most flexible
approach is to create an elliptical selection and then <a href="ch02s04s13.html" title="4.13. Stroking a Selection or Path">stroke</a> it. However, the quality of
anti-aliasing with this approach is rather crude. A higher
quality outline can be obtained by creating two elliptical
selections with different sizes, subtracting the inner one from
the outer one; however this is not always easy to get right.
</p>
<p>
FIXME
</p>
<div class="simplesect" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3320744"></a>How to Activate</h4>
</div>
</div>
</div>
<p>
The Rectangle Selection Tool can be activated from an image
menu as
<span class="guimenu">Tools</span>-><span class="guisubmenu">Selection Tools</span>-><span class="guimenuitem">Ellipse Select</span>;
from the Toolbox by clicking on the tool icon
<span class="guiicon">
<span class="inlinemediaobject"><img src="../images/toolbox/ellipsel.png" /></span>
</span>;
or from the keyboard using the shortcut <span><b class="keycap">e</b></span>.
</p>
</div>
<div class="simplesect" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3320566"></a>Key modifiers</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 colspan="2" align="left" valign="top">
<p>
See <a href="ch03s02.html#gimp-tool-select" title="2.1. Common Features">Selection Tools</a> for
help with modifier keys that affect all these tools in the same
way. Only effects that are specific to the Ellipse Select
tool are explained here.
</p>
</td>
</tr>
</table>
</div>
<div class="itemizedlist">
<ul type="disc">
<li>
<p>
<span><b class="keycap">Ctrl</b></span>: Pressing the Ctrl key after starting
your selection, and holding it down until you are finished,
causes your starting point to be used as the center of the
selected ellipse, instead of a corner. Note that if you
press the Ctrl key <span class="emphasis"><em>before</em></span> starting to
make the selection, the resulting selection will be
subtracted from the existing selection.
</p>
</li>
<li>
<p>
<span><b class="keycap">Shift</b></span>: Pressing the Shift key after starting
your selection, and holding it down until you are finished,
constrains the selection to be a circle. Note that if you
press the Shift key <span class="emphasis"><em>before</em></span> starting to
make the selection, the resulting selection will be
added to the existing selection.
</p>
</li>
<li>
<p>
<span><b class="keycap">Ctrl</b></span>-<span><b class="keycap">Shift</b></span>: Pressing both keys combines the two effects,
giving you a circular selection centered on your starting
point.
</p>
</li>
</ul>
</div>
</div>
<div class="simplesect" lang="en" xml:lang="en">
<div class="titlepage">
<div>
<div>
<h4 class="title"><a id="id3320657"></a>Options</h4>
</div>
</div>
</div>
<div class="informalfigure">
<div class="mediaobject">
<img src="../images/toolbox/tool-options-ellipsel.png" />
<div class="caption">
<p>
Tool Options for the Ellipse Select tool
</p>
</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 colspan="2" align="left" valign="top">
<p>
See <a href="ch03s02.html#gimp-tool-select" title="2.1. Common Features">Selection Tools</a> for
help with options that are common to all these tools. Only
options that are specific to the Ellipse Select
tool are described here.
</p>
</td>
</tr>
</table>
</div>
<div class="variablelist">
<dl>
<dt>
<span class="term">Antialiasing</span>
</dt>
<dd>
<p>
Checking this option will make the edge of the selection
appear smoother, by partially selecting pixels that the edge
passes through. The idea of antialiasing is discussed in
more detail under the glossary entry <a href="go01.html#glossary-antialiasing">Antialiasing</a>. You
will probably find that you get more satisfactory results by
using it, in most cases. The main situation where you might
want not to use it is in cutting and pasting, where partial
selection can sometimes create strange color fringes.
</p>
</dd>
<dt>
<span class="term">Auto Shrink Selection</span>
</dt>
<dd>
<p>
The <span class="guilabel">Auto Shrink Selection</span> checkbox will
make your next selection automatically shrink to the nearest
elliptical shape available on the image layer. The
algorithm for finding the best ellipse to shrink to is
"intelligent", which in this case means that it sometimes
does surprisingly sophisticated things, and sometimes does
surprisingly strange things. In any case, if the region
that you want to select has a solid-colored surround,
auto-shrinking will always pick it out correctly. Note that
the resulting elliptical selection does not need to have the
same shape as the one you sweep out.
</p>
<p>
If <span class="guilabel">Sample Merged</span> is also enabled, then
the Auto Shrink will use the pixel information from all the
layers of the image. For further information regarding Sample
Merge, see the glossary entry <a href="go01.html#glossary-samplemerge">Sample Merged</a>.
</p>
</dd>
<dt>
<span class="term">Size Constraints</span>
</dt>
<dd>
<div class="informalfigure">
<div class="mediaobject">
<img src="../images/toolbox/tool-options-rectsel-size.png" />
<div class="caption">
<p>
Size Constraint Option Menu for the Ellipse Select tool
</p>
</div>
</div>
</div>
<p>
This menu allows you the option of constraining the shape of
the ellipse in three different ways.
</p>
<div class="itemizedlist">
<ul type="disc">
<li>
<p><b>Free Select. </b>
This option places no constraint on the ellipse.
</p>
</li>
<li>
<p><b>Fixed Size. </b>
This will allow you to manually specify a size for the
selection using the Width, Height, and Unit controls.
</p>
</li>
<li>
<p><b>Fixed Aspect Ratio. </b>
This option allows you to resize the selection while
keeping the aspect ratio fixed according to the two numbers
entered in the Width and Height controls.
</p>
</li>
</ul>
</div>
</dd>
</dl>
</div>
</div>
</div>
<div class="navfooter">
<hr />
<table width="100%" summary="Navigation footer">
<tr>
<td width="40%" align="left"><a accesskey="p" href="ch03s02s02.html">Prev</a> </td>
<td width="20%" align="center">
<a accesskey="u" href="ch03s02.html">Up</a>
</td>
<td width="40%" align="right"> <a accesskey="n" href="ch03s02s04.html">Next</a></td>
</tr>
<tr>
<td width="40%" align="left" valign="top">2.2. Rectangle Selection Tool </td>
<td width="20%" align="center">
<a accesskey="h" href="index.html">Home</a>
</td>
<td width="40%" align="right" valign="top"> 2.4. Free Selection Tool (Lasso)</td>
</tr>
</table>
</div>
</body>
</html>
|
