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1---
2title: 'SkPath Overview'
3linkTitle: 'SkPath Overview'
4
5weight: 270
6---
7
8<a href='https://api.skia.org/classSkPath.html'>Path</a> contains
9<a href='undocumented#Line'>Lines</a> and
10<a href='undocumented#Curve'>Curves</a> which can be stroked or filled.
11<a href='#Contour'>Contour</a> is composed of a series of connected
12<a href='undocumented#Line'>Lines</a> and
13<a href='undocumented#Curve'>Curves</a>.
14<a href='https://api.skia.org/classSkPath.html'>Path</a> may contain zero, one,
15or more <a href='#Contour'>Contours</a>. Each
16<a href='undocumented#Line'>Line</a> and <a href='undocumented#Curve'>Curve</a>
17are described by Verb,
18<a href='https://api.skia.org/structSkPoint.html'>Points</a>, and optional
19<a href='#Path_Conic_Weight'>Path_Conic_Weight</a>.
20
21Each pair of connected <a href='undocumented#Line'>Lines</a> and
22<a href='undocumented#Curve'>Curves</a> share common
23<a href='https://api.skia.org/structSkPoint.html'>Point</a>; for instance,
24<a href='https://api.skia.org/classSkPath.html'>Path</a> containing two
25connected <a href='undocumented#Line'>Lines</a> are described the
26<a href='#Path_Verb'>Path_Verb</a> sequence:
27<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a>,
28<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kLine_Verb'>kLine_Verb</a>,
29<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kLine_Verb'>kLine_Verb</a>;
30and a <a href='https://api.skia.org/structSkPoint.html'>Point</a> sequence with
31three entries, sharing the middle entry as the end of the first
32<a href='undocumented#Line'>Line</a> and the start of the second
33<a href='undocumented#Line'>Line</a>.
34
35<a href='https://api.skia.org/classSkPath.html'>Path</a> components
36<a href='undocumented#Arc'>Arc</a>,
37<a href='https://api.skia.org/classSkPath.html#af037025a1adad16072abbbcd83b621f2'>Rect</a>,
38<a href='#RRect'>Round_Rect</a>, <a href='undocumented#Circle'>Circle</a>, and
39<a href='undocumented#Oval'>Oval</a> are composed of
40<a href='undocumented#Line'>Lines</a> and
41<a href='undocumented#Curve'>Curves</a> with as many
42<a href='https://api.skia.org/classSkPath.html#ac36f638ac96f3428626e993eacf84ff0'>Verbs</a>
43and <a href='https://api.skia.org/structSkPoint.html'>Points</a> required for an
44exact description. Once added to
45<a href='https://api.skia.org/classSkPath.html'>Path</a>, these components may
46lose their identity; although
47<a href='https://api.skia.org/classSkPath.html'>Path</a> can be inspected to
48determine if it describes a single
49<a href='https://api.skia.org/classSkPath.html#af037025a1adad16072abbbcd83b621f2'>Rect</a>,
50<a href='undocumented#Oval'>Oval</a>, <a href='#RRect'>Round_Rect</a>, and so
51on.
52
53### Example
54
55<div><fiddle-embed name="93887af0c1dac49521972698cf04069c"><div><a href='https://api.skia.org/classSkPath.html'>Path</a> contains three <a href='#Contour'>Contours</a>: <a href='undocumented#Line'>Line</a>, <a href='undocumented#Circle'>Circle</a>, and <a href='https://api.skia.org/classSkPath.html#ad75d5a934476ac6543d6d7ddd8dbb90a'>Quad</a>. <a href='undocumented#Line'>Line</a> is stroked but
56not filled. <a href='undocumented#Circle'>Circle</a> is stroked and filled; <a href='undocumented#Circle'>Circle</a> stroke forms a loop. <a href='https://api.skia.org/classSkPath.html#ad75d5a934476ac6543d6d7ddd8dbb90a'>Quad</a>
57is stroked and filled, but since it is not closed, <a href='https://api.skia.org/classSkPath.html#ad75d5a934476ac6543d6d7ddd8dbb90a'>Quad</a> does not stroke a loop.
58</div></fiddle-embed></div>
59
60<a href='https://api.skia.org/classSkPath.html'>Path</a> contains a
61<a href='#Path_Fill_Type'>Path_Fill_Type</a> which determines whether
62overlapping <a href='#Contour'>Contours</a> form fills or holes.
63<a href='#Path_Fill_Type'>Path_Fill_Type</a> also determines whether area inside
64or outside <a href='undocumented#Line'>Lines</a> and
65<a href='undocumented#Curve'>Curves</a> is filled.
66
67### Example
68
69<div><fiddle-embed name="36a995442c081ee779ecab2962d36e69"><div><a href='https://api.skia.org/classSkPath.html'>Path</a> is drawn filled, then stroked, then stroked and filled.
70</div></fiddle-embed></div>
71
72<a href='https://api.skia.org/classSkPath.html'>Path</a> contents are never
73shared. Copying <a href='https://api.skia.org/classSkPath.html'>Path</a> by
74value effectively creates a new
75<a href='https://api.skia.org/classSkPath.html'>Path</a> independent of the
76original. Internally, the copy does not duplicate its contents until it is
77edited, to reduce memory use and improve performance.
78
79<a name='Contour'></a>
80
81---
82
83<a href='#Contour'>Contour</a> contains one or more
84<a href='https://api.skia.org/classSkPath.html#ac36f638ac96f3428626e993eacf84ff0'>Verbs</a>,
85and as many <a href='https://api.skia.org/structSkPoint.html'>Points</a> as are
86required to satisfy <a href='#Path_Verb_Array'>Path_Verb_Array</a>. First
87<a href='#Path_Verb'>Path_Verb</a> in
88<a href='https://api.skia.org/classSkPath.html'>Path</a> is always
89<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a>;
90each
91<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a>
92that follows starts a new <a href='#Contour'>Contour</a>.
93
94### Example
95
96<div><fiddle-embed name="0374f2dcd7effeb1dd435205a6c2de6f"><div>Each <a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_moveTo'>moveTo</a> starts a new <a href='#Contour'>Contour</a>, and content after <a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_close'>close()</a>
97also starts a new <a href='#Contour'>Contour</a>. Since <a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_conicTo'>conicTo</a> is not preceded by
98<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_moveTo'>moveTo</a>, the first <a href='https://api.skia.org/structSkPoint.html'>Point</a> of the third <a href='#Contour'>Contour</a> starts at the last <a href='https://api.skia.org/structSkPoint.html'>Point</a>
99of the second <a href='#Contour'>Contour</a>.
100</div></fiddle-embed></div>
101
102If final <a href='#Path_Verb'>Path_Verb</a> in <a href='#Contour'>Contour</a> is
103<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kClose_Verb'>kClose_Verb</a>,
104<a href='undocumented#Line'>Line</a> connects
105<a href='#Path_Last_Point'>Path_Last_Point</a> in <a href='#Contour'>Contour</a>
106with first <a href='https://api.skia.org/structSkPoint.html'>Point</a>. A closed
107<a href='#Contour'>Contour</a>, stroked, draws
108<a href='#Paint_Stroke_Join'>Paint_Stroke_Join</a> at
109<a href='#Path_Last_Point'>Path_Last_Point</a> and first
110<a href='https://api.skia.org/structSkPoint.html'>Point</a>. Without
111<a href='https://api.skia.org/classSkPath.html'>SkPath</a>::<a href='#SkPath_kClose_Verb'>kClose_Verb</a>
112as final Verb, <a href='#Path_Last_Point'>Path_Last_Point</a> and first
113<a href='https://api.skia.org/structSkPoint.html'>Point</a> are not connected;
114<a href='#Contour'>Contour</a> remains open. An open
115<a href='#Contour'>Contour</a>, stroked, draws
116<a href='#Paint_Stroke_Cap'>Paint_Stroke_Cap</a> at
117<a href='#Path_Last_Point'>Path_Last_Point</a> and first
118<a href='https://api.skia.org/structSkPoint.html'>Point</a>.
119
120### Example
121
122<div><fiddle-embed name="7a1f39b12d2cd8b7f5b1190879259cb2"><div><a href='https://api.skia.org/classSkPath.html'>Path</a> is drawn stroked, with an open <a href='#Contour'>Contour</a> and a closed <a href='#Contour'>Contour</a>.
123</div></fiddle-embed></div>
124
125<a name='Contour_Zero_Length'></a>
126
127---
128
129<a href='#Contour'>Contour</a> length is distance traveled from first
130<a href='https://api.skia.org/structSkPoint.html'>Point</a> to
131<a href='#Path_Last_Point'>Path_Last_Point</a>, plus, if
132<a href='#Contour'>Contour</a> is closed, distance from
133<a href='#Path_Last_Point'>Path_Last_Point</a> to first
134<a href='https://api.skia.org/structSkPoint.html'>Point</a>. Even if
135<a href='#Contour'>Contour</a> length is zero, stroked
136<a href='undocumented#Line'>Lines</a> are drawn if
137<a href='#Paint_Stroke_Cap'>Paint_Stroke_Cap</a> makes them visible.
138
139### Example
140
141<div><fiddle-embed name="62848df605af6258653d9e16b27d8f7f"></fiddle-embed></div>
142