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      1 SkPath Overview
      2 ===
      3 <a href='SkPath_Reference#Path'>Path</a> contains <a href='undocumented#Line'>Lines</a> and <a href='undocumented#Curve'>Curves</a> which can be stroked or filled. <a href='SkPath_Overview#Contour'>Contour</a> is
      4 composed of a series of connected <a href='undocumented#Line'>Lines</a> and <a href='undocumented#Curve'>Curves</a>. <a href='SkPath_Reference#Path'>Path</a> may contain zero,
      5 one, or more <a href='SkPath_Overview#Contour'>Contours</a>.
      6 Each <a href='undocumented#Line'>Line</a> and <a href='undocumented#Curve'>Curve</a> are described by Verb, <a href='SkPoint_Reference#Point'>Points</a>, and optional <a href='#Path_Conic_Weight'>Path_Conic_Weight</a>.
      7 
      8 Each pair of connected <a href='undocumented#Line'>Lines</a> and <a href='undocumented#Curve'>Curves</a> share common <a href='SkPoint_Reference#Point'>Point</a>; for instance, <a href='SkPath_Reference#Path'>Path</a>
      9 containing two connected <a href='undocumented#Line'>Lines</a> are described the <a href='#Path_Verb'>Path_Verb</a> sequence:
     10 <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a>, <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kLine_Verb'>kLine_Verb</a>, <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kLine_Verb'>kLine_Verb</a>; and a <a href='SkPoint_Reference#Point'>Point</a> sequence
     11 with three entries, sharing
     12 the middle entry as the end of the first <a href='undocumented#Line'>Line</a> and the start of the second <a href='undocumented#Line'>Line</a>.
     13 
     14 <a href='SkPath_Reference#Path'>Path</a> components <a href='undocumented#Arc'>Arc</a>, <a href='SkRect_Reference#Rect'>Rect</a>, <a href='#RRect'>Round_Rect</a>, <a href='undocumented#Circle'>Circle</a>, and <a href='undocumented#Oval'>Oval</a> are composed of
     15 <a href='undocumented#Line'>Lines</a> and <a href='undocumented#Curve'>Curves</a> with as many <a href='SkPath_Reference#Verb'>Verbs</a> and <a href='SkPoint_Reference#Point'>Points</a> required
     16 for an exact description. Once added to <a href='SkPath_Reference#Path'>Path</a>, these components may lose their
     17 identity; although <a href='SkPath_Reference#Path'>Path</a> can be inspected to determine if it describes a single
     18 <a href='SkRect_Reference#Rect'>Rect</a>, <a href='undocumented#Oval'>Oval</a>, <a href='#RRect'>Round_Rect</a>, and so on.
     19 
     20 ### Example
     21 
     22 <div><fiddle-embed name="93887af0c1dac49521972698cf04069c"><div><a href='SkPath_Reference#Path'>Path</a> contains three <a href='SkPath_Overview#Contour'>Contours</a>: <a href='undocumented#Line'>Line</a>, <a href='undocumented#Circle'>Circle</a>, and <a href='SkPath_Reference#Quad'>Quad</a>. <a href='undocumented#Line'>Line</a> is stroked but
     23 not filled. <a href='undocumented#Circle'>Circle</a> is stroked and filled; <a href='undocumented#Circle'>Circle</a> stroke forms a loop. <a href='SkPath_Reference#Quad'>Quad</a>
     24 is stroked and filled, but since it is not closed, <a href='SkPath_Reference#Quad'>Quad</a> does not stroke a loop.
     25 </div></fiddle-embed></div>
     26 
     27 <a href='SkPath_Reference#Path'>Path</a> contains a <a href='#Path_Fill_Type'>Path_Fill_Type</a> which determines whether overlapping <a href='SkPath_Overview#Contour'>Contours</a>
     28 form fills or holes. <a href='#Path_Fill_Type'>Path_Fill_Type</a> also determines whether area inside or outside
     29 <a href='undocumented#Line'>Lines</a> and <a href='undocumented#Curve'>Curves</a> is filled.
     30 
     31 ### Example
     32 
     33 <div><fiddle-embed name="36a995442c081ee779ecab2962d36e69"><div><a href='SkPath_Reference#Path'>Path</a> is drawn filled, then stroked, then stroked and filled.
     34 </div></fiddle-embed></div>
     35 
     36 <a href='SkPath_Reference#Path'>Path</a> contents are never shared. Copying <a href='SkPath_Reference#Path'>Path</a> by value effectively creates
     37 a new <a href='SkPath_Reference#Path'>Path</a> independent of the original. Internally, the copy does not duplicate
     38 its contents until it is edited, to reduce memory use and improve performance.
     39 
     40 <a name='Contour'></a>
     41 
     42 ---
     43 
     44 <a href='SkPath_Overview#Contour'>Contour</a> contains one or more <a href='SkPath_Reference#Verb'>Verbs</a>, and as many <a href='SkPoint_Reference#Point'>Points</a> as
     45 are required to satisfy <a href='#Path_Verb_Array'>Path_Verb_Array</a>. First <a href='#Path_Verb'>Path_Verb</a> in <a href='SkPath_Reference#Path'>Path</a> is always
     46 <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a>; each <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kMove_Verb'>kMove_Verb</a> that follows starts a new <a href='SkPath_Overview#Contour'>Contour</a>.
     47 
     48 ### Example
     49 
     50 <div><fiddle-embed name="0374f2dcd7effeb1dd435205a6c2de6f"><div>Each <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_moveTo'>moveTo</a> starts a new <a href='SkPath_Overview#Contour'>Contour</a>, and content after <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_close'>close()</a>
     51 also starts a new <a href='SkPath_Overview#Contour'>Contour</a>. Since <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_conicTo'>conicTo</a> is not preceded by
     52 <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_moveTo'>moveTo</a>, the first <a href='SkPoint_Reference#Point'>Point</a> of the third <a href='SkPath_Overview#Contour'>Contour</a> starts at the last <a href='SkPoint_Reference#Point'>Point</a>
     53 of the second <a href='SkPath_Overview#Contour'>Contour</a>.
     54 </div></fiddle-embed></div>
     55 
     56 If final <a href='#Path_Verb'>Path_Verb</a> in <a href='SkPath_Overview#Contour'>Contour</a> is <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kClose_Verb'>kClose_Verb</a>, <a href='undocumented#Line'>Line</a> connects <a href='#Path_Last_Point'>Path_Last_Point</a> in
     57 <a href='SkPath_Overview#Contour'>Contour</a> with first <a href='SkPoint_Reference#Point'>Point</a>. A closed <a href='SkPath_Overview#Contour'>Contour</a>, stroked, draws
     58 <a href='#Paint_Stroke_Join'>Paint_Stroke_Join</a> at <a href='#Path_Last_Point'>Path_Last_Point</a> and first <a href='SkPoint_Reference#Point'>Point</a>. Without <a href='SkPath_Reference#SkPath'>SkPath</a>::<a href='#SkPath_kClose_Verb'>kClose_Verb</a>
     59 as final Verb, <a href='#Path_Last_Point'>Path_Last_Point</a> and first <a href='SkPoint_Reference#Point'>Point</a> are not connected; <a href='SkPath_Overview#Contour'>Contour</a>
     60 remains open. An open <a href='SkPath_Overview#Contour'>Contour</a>, stroked, draws <a href='#Paint_Stroke_Cap'>Paint_Stroke_Cap</a> at
     61 <a href='#Path_Last_Point'>Path_Last_Point</a> and first <a href='SkPoint_Reference#Point'>Point</a>.
     62 
     63 ### Example
     64 
     65 <div><fiddle-embed name="7a1f39b12d2cd8b7f5b1190879259cb2"><div><a href='SkPath_Reference#Path'>Path</a> is drawn stroked, with an open <a href='SkPath_Overview#Contour'>Contour</a> and a closed <a href='SkPath_Overview#Contour'>Contour</a>.
     66 </div></fiddle-embed></div>
     67 
     68 <a name='Contour_Zero_Length'></a>
     69 
     70 ---
     71 
     72 <a href='SkPath_Overview#Contour'>Contour</a> length is distance traveled from first <a href='SkPoint_Reference#Point'>Point</a> to <a href='#Path_Last_Point'>Path_Last_Point</a>,
     73 plus, if <a href='SkPath_Overview#Contour'>Contour</a> is closed, distance from <a href='#Path_Last_Point'>Path_Last_Point</a> to first <a href='SkPoint_Reference#Point'>Point</a>.
     74 Even if <a href='SkPath_Overview#Contour'>Contour</a> length is zero, stroked <a href='undocumented#Line'>Lines</a> are drawn if <a href='#Paint_Stroke_Cap'>Paint_Stroke_Cap</a>
     75 makes them visible.
     76 
     77 ### Example
     78 
     79 <div><fiddle-embed name="62848df605af6258653d9e16b27d8f7f"></fiddle-embed></div>
     80 
     81