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SkPoint Reference
===

# <a name="Point"></a> Point

## <a name="Overview"></a> Overview

## <a name="Overview_Subtopic"></a> Overview Subtopic

| name | description |
| --- | --- |
| <a href="#Constructor">Constructor</a> | functions that construct <a href="#SkPoint">SkPoint</a> |
| <a href="#Member_Function">Member Function</a> | static functions and member methods |
| <a href="#Member">Member</a> | member values |
| <a href="#Operator">Operator</a> | operator overloading methods |
| <a href="#Related_Function">Related Function</a> | similar methods grouped together |

# <a name="SkPoint"></a> Struct SkPoint
<a href="#SkPoint">SkPoint</a> holds two 32 bit floating point coordinates.

## <a name="Related_Function"></a> Related Function

| name | description |
| --- | --- |
| <a href="#SkPoint_Offset">Offset</a> | moves sides |
| <a href="#Property">Property</a> | member values |
| <a href="#Set">Set</a> | replaces all values |

## <a name="Member_Function"></a> Member Function

| name | description |
| --- | --- |
| <a href="#SkPoint_CrossProduct">CrossProduct</a> | returns cross product |
| <a href="#SkPoint_Distance">Distance</a> | returns straight-line distance between points |
| <a href="#SkPoint_DotProduct">DotProduct</a> | returns dot product |
| <a href="#SkPoint_Length">Length</a> | returns straight-line distance to origin |
| <a href="#SkPoint_Make">Make</a> | constructs from <a href="undocumented#SkScalar">SkScalar</a> inputs |
| <a href="#SkPoint_Normalize">Normalize</a> | sets length to one, and returns prior length |
| <a href="#SkPoint_Offset">Offset</a> | translates <a href="#Point">Point</a> array |
| <a href="#SkPoint_cross">cross</a> | returns cross product |
| <a href="#SkPoint_distanceToOrigin">distanceToOrigin</a> | returns straight-line distance to origin |
| <a href="#SkPoint_dot">dot</a> | returns dot product |
| <a href="#SkPoint_equals">equals</a> | returns true if <a href="#Point">Points</a> are equal |
| <a href="#SkPoint_isFinite">isFinite</a> | returns true if no member is infinite or NaN |
| <a href="#SkPoint_isZero">isZero</a> | returns true if both members equal zero |
| <a href="#SkPoint_iset">iset</a> | sets to integer input |
| <a href="#SkPoint_length">length</a> | returns straight-line distance to origin |
| <a href="#SkPoint_negate">negate</a> | reverses the sign of both members |
| <a href="#SkPoint_normalize">normalize</a> | sets length to one, preserving direction |
| <a href="#SkPoint_offset">offset</a> | translates <a href="#Point">Point</a> |
| <a href="#SkPoint_scale">scale</a> | multiplies <a href="#Point">Point</a> by scale factor |
| <a href="#SkPoint_set">set</a> | sets to <a href="undocumented#SkScalar">SkScalar</a> input |
| <a href="#SkPoint_setAbs">setAbs</a> | sets sign of both members to positive |
| <a href="#SkPoint_setLength">setLength</a> | sets straight-line distance to origin |
| <a href="#SkPoint_setNormalize">setNormalize</a> | sets length to one, in direction of (x, y) |
| <a href="#SkPoint_x">x</a> | returns <a href="#SkPoint_fX">fX</a> |
| <a href="#SkPoint_y">y</a> | returns <a href="#SkPoint_fY">fY</a> |

## <a name="Member"></a> Member

| name | description |
| --- | --- |
| <a href="#SkPoint_fX">fX</a> | x-axis value |
| <a href="#SkPoint_fY">fY</a> | y-axis value |

<a name="SkPoint_fX"> <code><strong>SkScalar  fX</strong></code> </a>

x-axis value used by both <a href="#Point">Point</a> and <a href="#Vector">Vector</a>. May contain any value, including
infinities and NaN.

<a name="SkPoint_fY"> <code><strong>SkScalar  fY</strong></code> </a>

y-axis value used by both <a href="#Point">Point</a> and <a href="#Vector">Vector</a>. May contain any value, including
infinities and NaN.

## <a name="Constructor"></a> Constructor

| name | description |
| --- | --- |
| <a href="#SkPoint_Make">Make</a> | constructs from <a href="undocumented#SkScalar">SkScalar</a> inputs |

<a name="SkPoint_Make"></a>
## Make

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static constexpr SkPoint Make(SkScalar x, SkScalar y)
</pre>

Sets <a href="#SkPoint_fX">fX</a> to x, <a href="#SkPoint_fY">fY</a> to y. Used both to set <a href="#Point">Point</a> and <a href="#Vector">Vector</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Make_x"> <code><strong>x </strong></code> </a></td> <td>
<a href="undocumented#SkScalar">SkScalar</a> x-axis value of constructed <a href="#Point">Point</a> or <a href="#Vector">Vector</a></td>
  </tr>  <tr>    <td><a name="SkPoint_Make_y"> <code><strong>y </strong></code> </a></td> <td>
<a href="undocumented#SkScalar">SkScalar</a> y-axis value of constructed <a href="#Point">Point</a> or <a href="#Vector">Vector</a></td>
  </tr>
</table>

### Return Value

<a href="#Point">Point</a> (x, y)

### Example

<div><fiddle-embed name="d266e70977847001f7c42f8a2513bee7">

#### Example Output

~~~~
all equal
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_set">set</a> <a href="#SkPoint_iset">iset</a><sup><a href="#SkPoint_iset_2">[2]</a></sup> <a href="SkIPoint_Reference#SkIPoint_Make">SkIPoint::Make</a>

---

## <a name="Property"></a> Property

| name | description |
| --- | --- |
| <a href="#SkPoint_Distance">Distance</a> | returns straight-line distance between points |
| <a href="#SkPoint_Length">Length</a> | returns straight-line distance to origin |
| <a href="#SkPoint_distanceToOrigin">distanceToOrigin</a> | returns straight-line distance to origin |
| <a href="#SkPoint_isFinite">isFinite</a> | returns true if no member is infinite or NaN |
| <a href="#SkPoint_isZero">isZero</a> | returns true if both members equal zero |
| <a href="#SkPoint_length">length</a> | returns straight-line distance to origin |
| <a href="#SkPoint_x">x</a> | returns <a href="#SkPoint_fX">fX</a> |
| <a href="#SkPoint_y">y</a> | returns <a href="#SkPoint_fY">fY</a> |

<a name="SkPoint_x"></a>
## x

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar x() const
</pre>

Returns x-axis value of <a href="#Point">Point</a> or <a href="#Vector">Vector</a>.

### Return Value

<a href="#SkPoint_fX">fX</a>

### Example

<div><fiddle-embed name="9f3fe446b800ae1d940785d438634941">

#### Example Output

~~~~
pt1.fX == pt1.x()
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_y">y</a> <a href="SkIPoint_Reference#SkIPoint_x">SkIPoint::x()</a>

---

<a name="SkPoint_y"></a>
## y

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar y() const
</pre>

Returns y-axis value of <a href="#Point">Point</a> or <a href="#Vector">Vector</a>.

### Return Value

<a href="#SkPoint_fY">fY</a>

### Example

<div><fiddle-embed name="4c962850c2dbea4d2325df469400680e">

#### Example Output

~~~~
pt1.fY == pt1.y()
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_x">x</a> <a href="SkIPoint_Reference#SkIPoint_y">SkIPoint::y()</a>

---

<a name="SkPoint_isZero"></a>
## isZero

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool isZero() const
</pre>

Returns true if <a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a> are both zero.

### Return Value

true if <a href="#SkPoint_fX">fX</a> is zero and <a href="#SkPoint_fY">fY</a> is zero

### Example

<div><fiddle-embed name="81b9665110b88ef6bcbc20464aed7da1">

#### Example Output

~~~~
pt.fX=+0 pt.fY=-0
pt.isZero() == true
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_isFinite">isFinite</a> <a href="SkIPoint_Reference#SkIPoint_isZero">SkIPoint::isZero</a>

---

## <a name="Set"></a> Set

| name | description |
| --- | --- |
| <a href="#SkPoint_iset">iset</a> | sets to integer input |
|  | <a href="#SkPoint_iset">iset(int32 t x, int32 t y)</a> |
|  | <a href="#SkPoint_iset_2">iset(const SkIPoint& p)</a> |
| <a href="#SkPoint_normalize">normalize</a> | sets length to one, preserving direction |
| <a href="#SkPoint_set">set</a> | sets to <a href="undocumented#SkScalar">SkScalar</a> input |
| <a href="#SkPoint_setAbs">setAbs</a> | sets sign of both members to positive |
| <a href="#SkPoint_setLength">setLength</a> | sets straight-line distance to origin |
|  | <a href="#SkPoint_setLength">setLength(SkScalar length)</a> |
|  | <a href="#SkPoint_setLength_2">setLength(SkScalar x, SkScalar y, SkScalar length)</a> |
| <a href="#SkPoint_setNormalize">setNormalize</a> | sets length to one, in direction of (x, y) |

<a name="SkPoint_set"></a>
## set

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void set(SkScalar x, SkScalar y)
</pre>

Sets <a href="#SkPoint_fX">fX</a> to x and <a href="#SkPoint_fY">fY</a> to y.

### Parameters

<table>  <tr>    <td><a name="SkPoint_set_x"> <code><strong>x </strong></code> </a></td> <td>
new value for <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_set_y"> <code><strong>y </strong></code> </a></td> <td>
new value for <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="d08d1e7dafcad4342d1619fdbb2f5781">

#### Example Output

~~~~
pt1 == pt2
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_iset">iset</a><sup><a href="#SkPoint_iset_2">[2]</a></sup> <a href="#SkPoint_Make">Make</a>

---

<a name="SkPoint_iset"></a>
## iset

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void iset(int32_t x, int32_t y)
</pre>

Sets <a href="#SkPoint_fX">fX</a> to x and <a href="#SkPoint_fY">fY</a> to y, promoting integers to <a href="undocumented#SkScalar">SkScalar</a> values.

Assigning a large integer value directly to <a href="#SkPoint_fX">fX</a> or <a href="#SkPoint_fY">fY</a> may cause a compiler
error, triggered by narrowing conversion of int to <a href="undocumented#SkScalar">SkScalar</a>. This safely
casts x and y to avoid the error.

### Parameters

<table>  <tr>    <td><a name="SkPoint_iset_x"> <code><strong>x </strong></code> </a></td> <td>
new value for <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_iset_y"> <code><strong>y </strong></code> </a></td> <td>
new value for <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="0d9e8ed734981b5b113f22c7bfde5357"></fiddle-embed></div>

### See Also

<a href="#SkPoint_set">set</a> <a href="#SkPoint_Make">Make</a> <a href="SkIPoint_Reference#SkIPoint_set">SkIPoint::set</a>

---

<a name="SkPoint_iset_2"></a>

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void iset(const SkIPoint& p)
</pre>

Sets <a href="#SkPoint_fX">fX</a> to <a href="#SkPoint_iset_2_p">p</a>.<a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a> to <a href="#SkPoint_iset_2_p">p</a>.<a href="#SkPoint_fY">fY</a>, promoting integers to <a href="undocumented#SkScalar">SkScalar</a> values.

Assigning an <a href="SkIPoint_Reference#IPoint">IPoint</a> containing a large integer value directly to <a href="#SkPoint_fX">fX</a> or <a href="#SkPoint_fY">fY</a> may
cause a compiler error, triggered by narrowing conversion of int to <a href="undocumented#SkScalar">SkScalar</a>.
This safely casts <a href="#SkPoint_iset_2_p">p</a>.<a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_iset_2_p">p</a>.<a href="#SkPoint_fY">fY</a> to avoid the error.

### Parameters

<table>  <tr>    <td><a name="SkPoint_iset_2_p"> <code><strong>p </strong></code> </a></td> <td>
<a href="SkIPoint_Reference#IPoint">IPoint</a> members promoted to <a href="undocumented#SkScalar">SkScalar</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="12b7164a769e232bb772f19c59600ee7">

#### Example Output

~~~~
iPt: -2147483647, 2147483647
fPt: -2.14748e+09, 2.14748e+09
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_set">set</a> <a href="#SkPoint_Make">Make</a> <a href="SkIPoint_Reference#SkIPoint_set">SkIPoint::set</a>

---

<a name="SkPoint_setAbs"></a>
## setAbs

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void setAbs(const SkPoint& pt)
</pre>

Sets <a href="#SkPoint_fX">fX</a> to absolute value of <a href="#SkPoint_setAbs_pt">pt</a>.<a href="#SkPoint_fX">fX</a>; and <a href="#SkPoint_fY">fY</a> to absolute value of <a href="#SkPoint_setAbs_pt">pt</a>.<a href="#SkPoint_fY">fY</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_setAbs_pt"> <code><strong>pt </strong></code> </a></td> <td>
members providing magnitude for <a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="7f70860e820b67a347cff03c00488426">

#### Example Output

~~~~
pt: 0, -0  abs: 0, 0
pt: -1, -2  abs: 1, 2
pt: inf, -inf  abs: inf, inf
pt: nan, -nan  abs: nan, nan
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_set">set</a> <a href="#SkPoint_Make">Make</a> <a href="#SkPoint_negate">negate</a>

---

## <a name="Offset"></a> Offset

| name | description |
| --- | --- |
| <a href="#SkPoint_Normalize">Normalize</a> | sets length to one, and returns prior length |
| <a href="#SkPoint_Offset">Offset</a> | translates <a href="#Point">Point</a> array |
|  | <a href="#SkPoint_Offset">Offset(SkPoint points[], int count, const SkVector& offset)</a> |
|  | <a href="#SkPoint_Offset_2">Offset(SkPoint points[], int count, SkScalar dx, SkScalar dy)</a> |
| <a href="#SkPoint_offset">offset</a> | translates <a href="#Point">Point</a> |
| <a href="#SkPoint_scale">scale</a> | multiplies <a href="#Point">Point</a> by scale factor |
|  | <a href="#SkPoint_scale">scale(SkScalar scale, SkPoint* dst)</a> const |
|  | <a href="#SkPoint_scale_2">scale(SkScalar value)</a> |

<a name="SkPoint_Offset"></a>
## Offset

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static void Offset(SkPoint points[], int count, const SkVector& offset)
</pre>

Adds offset to each <a href="#Point">Point</a> in <a href="#SkPoint_Offset_points">points</a> array with <a href="#SkPoint_Offset_count">count</a> entries.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Offset_points"> <code><strong>points </strong></code> </a></td> <td>
<a href="#Point">Point</a> array</td>
  </tr>  <tr>    <td><a name="SkPoint_Offset_count"> <code><strong>count </strong></code> </a></td> <td>
entries in array</td>
  </tr>  <tr>    <td><a name="SkPoint_Offset_offset"> <code><strong>offset </strong></code> </a></td> <td>
<a href="#Vector">Vector</a> added to <a href="#SkPoint_Offset_points">points</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="f0f24726df78a5d797bcf311e694a0a3"></fiddle-embed></div>

### See Also

<a href="#SkPoint_offset">offset</a> <a href="#SkPoint_addto_operator">operator+=(const SkVector& v)</a>

---

<a name="SkPoint_Offset_2"></a>

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static void Offset(SkPoint points[], int count, SkScalar dx, SkScalar dy)
</pre>

Adds offset (<a href="#SkPoint_Offset_2_dx">dx</a>, <a href="#SkPoint_Offset_2_dy">dy</a>) to each <a href="#Point">Point</a> in <a href="#SkPoint_Offset_2_points">points</a> array of length <a href="#SkPoint_Offset_2_count">count</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Offset_2_points"> <code><strong>points </strong></code> </a></td> <td>
<a href="#Point">Point</a> array</td>
  </tr>  <tr>    <td><a name="SkPoint_Offset_2_count"> <code><strong>count </strong></code> </a></td> <td>
entries in array</td>
  </tr>  <tr>    <td><a name="SkPoint_Offset_2_dx"> <code><strong>dx </strong></code> </a></td> <td>
added to <a href="#SkPoint_fX">fX</a> in <a href="#SkPoint_Offset_2_points">points</a></td>
  </tr>  <tr>    <td><a name="SkPoint_Offset_2_dy"> <code><strong>dy </strong></code> </a></td> <td>
added to <a href="#SkPoint_fY">fY</a> in <a href="#SkPoint_Offset_2_points">points</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="532849faa838de885b86d3ebffae3712"></fiddle-embed></div>

### See Also

<a href="#SkPoint_offset">offset</a> <a href="#SkPoint_addto_operator">operator+=(const SkVector& v)</a>

---

<a name="SkPoint_offset"></a>
## offset

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void offset(SkScalar dx, SkScalar dy)
</pre>

Adds offset (<a href="#SkPoint_offset_dx">dx</a>, <a href="#SkPoint_offset_dy">dy</a>) to <a href="#Point">Point</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_offset_dx"> <code><strong>dx </strong></code> </a></td> <td>
added to <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_offset_dy"> <code><strong>dy </strong></code> </a></td> <td>
added to <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="02750ceaa874f956e6e6544ef6b858ee"></fiddle-embed></div>

### See Also

<a href="#SkPoint_Offset">Offset</a><sup><a href="#SkPoint_Offset_2">[2]</a></sup> <a href="#SkPoint_addto_operator">operator+=(const SkVector& v)</a>

---

<a name="SkPoint_length"></a>
## length

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar length() const
</pre>

Returns the Euclidean_Distance from origin, computed as:

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
sqrt(fX * fX + fY * fY)</pre>

.

### Return Value

straight-line distance to origin

### Example

<div><fiddle-embed name="8363ab179447ee4b827679e20d3d81eb"></fiddle-embed></div>

### See Also

<a href="#SkPoint_distanceToOrigin">distanceToOrigin</a> <a href="#SkPoint_Length">Length</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_Distance">Distance</a>

---

<a name="SkPoint_distanceToOrigin"></a>
## distanceToOrigin

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar distanceToOrigin() const
</pre>

Returns the Euclidean_Distance from origin, computed as:

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
sqrt(fX * fX + fY * fY)</pre>

.

### Return Value

straight-line distance to origin

### Example

<div><fiddle-embed name="812cf26d91b1cdcd2c6b9438a8172518"></fiddle-embed></div>

### See Also

<a href="#SkPoint_length">length</a> <a href="#SkPoint_Length">Length</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_Distance">Distance</a>

---

<a name="SkPoint_normalize"></a>
## normalize

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool normalize()
</pre>

Scales (<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_fY">fY</a>) so that <a href="#SkPoint_length">length</a> returns one, while preserving ratio of <a href="#SkPoint_fX">fX</a> to <a href="#SkPoint_fY">fY</a>,
if possible. If prior length is nearly zero, sets <a href="#Vector">Vector</a> to (0, 0) and returns
false; otherwise returns true.

### Return Value

true if former length is not zero or nearly zero

### Example

<div><fiddle-embed name="d84fce292d86c7d9ef37ae2d179c03c7"></fiddle-embed></div>

### See Also

<a href="#SkPoint_Normalize">Normalize</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_length">length</a> <a href="#SkPoint_Length">Length</a>

---

<a name="SkPoint_setNormalize"></a>
## setNormalize

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool setNormalize(SkScalar x, SkScalar y)
</pre>

Sets <a href="#Vector">Vector</a> to (x, y) scaled so <a href="#SkPoint_length">length</a> returns one, and so that
(<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_fY">fY</a>) is proportional to (x, y).  If (x, y) length is nearly zero,
sets <a href="#Vector">Vector</a> to (0, 0) and returns false; otherwise returns true.

### Parameters

<table>  <tr>    <td><a name="SkPoint_setNormalize_x"> <code><strong>x </strong></code> </a></td> <td>
proportional value for <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_setNormalize_y"> <code><strong>y </strong></code> </a></td> <td>
proportional value for <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Return Value

true if (x, y) length is not zero or nearly zero

### Example

<div><fiddle-embed name="3e4f147d143a388802484bf0d26534c2"></fiddle-embed></div>

### See Also

<a href="#SkPoint_normalize">normalize</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup>

---

<a name="SkPoint_setLength"></a>
## setLength

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool setLength(SkScalar length)
</pre>

Scales <a href="#Vector">Vector</a> so that <a href="#SkPoint_distanceToOrigin">distanceToOrigin</a> returns length, if possible. If former
length is nearly zero, sets <a href="#Vector">Vector</a> to (0, 0) and return false; otherwise returns
true.

### Parameters

<table>  <tr>    <td><a name="SkPoint_setLength_length"> <code><strong>length </strong></code> </a></td> <td>
straight-line distance to origin</td>
  </tr>
</table>

### Return Value

true if former length is not zero or nearly zero

### Example

<div><fiddle-embed name="cbe7db206ece825aa3b9b7c3256aeaf0"></fiddle-embed></div>

### See Also

<a href="#SkPoint_length">length</a> <a href="#SkPoint_Length">Length</a> <a href="#SkPoint_setNormalize">setNormalize</a> <a href="#SkPoint_setAbs">setAbs</a>

---

<a name="SkPoint_setLength_2"></a>

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool setLength(SkScalar x, SkScalar y, SkScalar length)
</pre>

Sets <a href="#Vector">Vector</a> to (x, y) scaled to length, if possible. If former
length is nearly zero, sets <a href="#Vector">Vector</a> to (0, 0) and return false; otherwise returns
true.

### Parameters

<table>  <tr>    <td><a name="SkPoint_setLength_2_x"> <code><strong>x </strong></code> </a></td> <td>
proportional value for <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_setLength_2_y"> <code><strong>y </strong></code> </a></td> <td>
proportional value for <a href="#SkPoint_fY">fY</a></td>
  </tr>  <tr>    <td><a name="SkPoint_setLength_2_length"> <code><strong>length </strong></code> </a></td> <td>
straight-line distance to origin</td>
  </tr>
</table>

### Return Value

true if (x, y) length is not zero or nearly zero

### Example

<div><fiddle-embed name="3cc0662b6fbbee1fe3442a0acfece22c"></fiddle-embed></div>

### See Also

<a href="#SkPoint_length">length</a> <a href="#SkPoint_Length">Length</a> <a href="#SkPoint_setNormalize">setNormalize</a> <a href="#SkPoint_setAbs">setAbs</a>

---

## <a name="Operator"></a> Operator

| name | description |
| --- | --- |
| <a href="#SkPoint_CrossProduct">CrossProduct</a> | returns cross product |
| <a href="#SkPoint_DotProduct">DotProduct</a> | returns dot product |
| <a href="#SkPoint_cross">cross</a> | returns cross product |
| <a href="#SkPoint_dot">dot</a> | returns dot product |
| <a href="#SkPoint_equals">equals</a> | returns true if <a href="#Point">Points</a> are equal |
| <a href="#SkPoint_negate">negate</a> | reverses the sign of both members |
| <a href="#SkPoint_notequal_operator">operator!=(const SkPoint& a, const SkPoint& b)</a> | returns true if <a href="#Point">Point</a> are unequal |
| <a href="#SkPoint_multiply_operator">operator*(SkScalar scale) const</a> | returns <a href="#Point">Point</a> multiplied by scale |
| <a href="#SkPoint_multiplyby_operator">operator*=(SkScalar scale)</a> | multiplies <a href="#Point">Point</a> by scale factor |
| <a href="#SkPoint_add_operator">operator+(const SkPoint& a, const SkVector& b)</a> | returns <a href="#Point">Point</a> offset by <a href="#Vector">Vector</a> |
| <a href="#SkPoint_addto_operator">operator+=(const SkVector& v)</a> | adds <a href="#Vector">Vector</a> to <a href="#Point">Point</a> |
| <a href="#SkPoint_minus_operator">operator-() const</a> | reverses sign of <a href="#Point">Point</a> |
| <a href="#SkPoint_subtract_operator">operator-(const SkPoint& a, const SkPoint& b)</a> | returns <a href="#Vector">Vector</a> between <a href="#Point">Points</a> |
| <a href="#SkPoint_subtractfrom_operator">operator-=(const SkVector& v)</a> | subtracts <a href="#Vector">Vector</a> from <a href="#Point">Point</a> |
| <a href="#SkPoint_equal_operator">operator==(const SkPoint& a, const SkPoint& b)</a> | returns true if <a href="#Point">Point</a> are equal |

<a name="SkPoint_scale"></a>
## scale

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void scale(SkScalar scale, SkPoint* dst) const
</pre>

Sets <a href="#SkPoint_scale_dst">dst</a> to <a href="#Point">Point</a> times scale. <a href="#SkPoint_scale_dst">dst</a> may be <a href="#Point">Point</a> to modify <a href="#Point">Point</a> in place.

### Parameters

<table>  <tr>    <td><a name="SkPoint_scale_scale"> <code><strong>scale </strong></code> </a></td> <td>
factor to multiply <a href="#Point">Point</a> by</td>
  </tr>  <tr>    <td><a name="SkPoint_scale_dst"> <code><strong>dst </strong></code> </a></td> <td>
storage for scaled <a href="#Point">Point</a></td>
  </tr>
</table>

### Example

<div><fiddle-embed name="972e4e230806281adb928e068bcd8551"></fiddle-embed></div>

### See Also

<a href="#SkPoint_multiply_operator">operator*(SkScalar scale) const</a> <a href="#SkPoint_multiplyby_operator">operator*=(SkScalar scale)</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup>

---

<a name="SkPoint_scale_2"></a>

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void scale(SkScalar value)
</pre>

Scales <a href="#Point">Point</a> in place by scale.

### Parameters

<table>  <tr>    <td><a name="SkPoint_scale_2_value"> <code><strong>value </strong></code> </a></td> <td>
factor to multiply <a href="#Point">Point</a> by</td>
  </tr>
</table>

### Example

<div><fiddle-embed name="1060a4f27d8ef29519e6ac006ce90f2b"></fiddle-embed></div>

### See Also

<a href="#SkPoint_multiply_operator">operator*(SkScalar scale) const</a> <a href="#SkPoint_multiplyby_operator">operator*=(SkScalar scale)</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup>

---

<a name="SkPoint_negate"></a>
## negate

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void negate()
</pre>

Changes the sign of <a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a>.

### Example

<div><fiddle-embed name="312c0c8065ab5d0adfda80cccf2d11e6">

#### Example Output

~~~~
pt: 0, -0  negate: -0, 0
pt: -1, -2  negate: 1, 2
pt: inf, -inf  negate: -inf, inf
pt: nan, -nan  negate: -nan, nan
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_minus_operator">operator-() const</a> <a href="#SkPoint_setAbs">setAbs</a>

---

<a name="SkPoint_minus_operator"></a>
## operator-

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkPoint operator-() _const
</pre>

Returns <a href="#Point">Point</a> changing the signs of <a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a>.

### Return Value

<a href="#Point">Point</a> as (-<a href="#SkPoint_fX">fX</a>, -<a href="#SkPoint_fY">fY</a>)

### Example

<div><fiddle-embed name="9baf247cfcd8272c0ddf6ce93f676b37">

#### Example Output

~~~~
pt: 0, -0  negate: -0, 0
pt: -1, -2  negate: 1, 2
pt: inf, -inf  negate: -inf, inf
pt: nan, -nan  negate: -nan, nan
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_negate">negate</a> <a href="#SkPoint_subtract_operator">operator-(const SkPoint& a, const SkPoint& b)</a> <a href="#SkPoint_subtractfrom_operator">operator-=(const SkVector& v)</a> <a href="SkIPoint_Reference#SkIPoint_minus_operator">SkIPoint::operator-() const</a>

---

<a name="SkPoint_addto_operator"></a>
## operator+=

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void operator+=(const SkVector& v)
</pre>

Adds <a href="#Vector">Vector</a> <a href="#SkPoint_addto_operator_v">v</a> to <a href="#Point">Point</a>. Sets <a href="#Point">Point</a> to:
(<a href="#SkPoint_fX">fX</a> + <a href="#SkPoint_addto_operator_v">v</a>.<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_fY">fY</a> + <a href="#SkPoint_addto_operator_v">v</a>.<a href="#SkPoint_fY">fY</a>).

### Parameters

<table>  <tr>    <td><a name="SkPoint_addto_operator_v"> <code><strong>v </strong></code> </a></td> <td>
<a href="#Vector">Vector</a> to add</td>
  </tr>
</table>

### Example

<div><fiddle-embed name="8b4e79109e2381345258cb744881b20c"></fiddle-embed></div>

### See Also

<a href="#SkPoint_offset">offset</a> <a href="#SkPoint_add_operator">operator+(const SkPoint& a, const SkVector& b)</a> <a href="SkIPoint_Reference#SkIPoint_addto_operator">SkIPoint::operator+=(const SkIVector& v)</a>

---

<a name="SkPoint_subtractfrom_operator"></a>
## operator-=

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void operator-=(const SkVector& v)
</pre>

Subtracts <a href="#Vector">Vector</a> <a href="#SkPoint_subtractfrom_operator_v">v</a> from <a href="#Point">Point</a>. Sets <a href="#Point">Point</a> to:
(<a href="#SkPoint_fX">fX</a> - <a href="#SkPoint_subtractfrom_operator_v">v</a>.<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_fY">fY</a> - <a href="#SkPoint_subtractfrom_operator_v">v</a>.<a href="#SkPoint_fY">fY</a>).

### Parameters

<table>  <tr>    <td><a name="SkPoint_subtractfrom_operator_v"> <code><strong>v </strong></code> </a></td> <td>
<a href="#Vector">Vector</a> to subtract</td>
  </tr>
</table>

### Example

<div><fiddle-embed name="86c0399704d8dff4091bf87b8d87d40b"></fiddle-embed></div>

### See Also

<a href="#SkPoint_offset">offset</a> <a href="#SkPoint_subtract_operator">operator-(const SkPoint& a, const SkPoint& b)</a> <a href="SkIPoint_Reference#SkIPoint_subtractfrom_operator">SkIPoint::operator-=(const SkIVector& v)</a>

---

<a name="SkPoint_multiply_operator"></a>
## operator*

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkPoint operator*(SkScalar scale) _const
</pre>

Returns <a href="#Point">Point</a> multiplied by scale.

### Parameters

<table>  <tr>    <td><a name="SkPoint_multiply_operator_scale"> <code><strong>scale </strong></code> </a></td> <td>
<a href="undocumented#Scalar">Scalar</a> to multiply by</td>
  </tr>
</table>

### Return Value

<a href="#Point">Point</a> as (<a href="#SkPoint_fX">fX</a> * scale, <a href="#SkPoint_fY">fY</a> * scale)

### Example

<div><fiddle-embed name="35b3bc675779de043706ae4817ee950c"></fiddle-embed></div>

### See Also

<a href="#SkPoint_multiplyby_operator">operator*=(SkScalar scale)</a> <a href="#SkPoint_scale">scale</a><sup><a href="#SkPoint_scale_2">[2]</a></sup> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_setNormalize">setNormalize</a>

---

<a name="SkPoint_multiplyby_operator"></a>
## operator*=

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkPoint& operator*=(SkScalar scale)
</pre>

Multiplies <a href="#Point">Point</a> by scale. Sets <a href="#Point">Point</a> to:
(<a href="#SkPoint_fX">fX</a> * scale, <a href="#SkPoint_fY">fY</a> * scale)

### Parameters

<table>  <tr>    <td><a name="SkPoint_multiplyby_operator_scale"> <code><strong>scale </strong></code> </a></td> <td>
<a href="undocumented#Scalar">Scalar</a> to multiply by</td>
  </tr>
</table>

### Return Value

reference to <a href="#Point">Point</a>

### Example

<div><fiddle-embed name="3ce3db36235d80dbac4d39504cf756da"></fiddle-embed></div>

### See Also

<a href="#SkPoint_multiply_operator">operator*(SkScalar scale) const</a> <a href="#SkPoint_scale">scale</a><sup><a href="#SkPoint_scale_2">[2]</a></sup> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_setNormalize">setNormalize</a>

---

<a name="SkPoint_isFinite"></a>
## isFinite

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool isFinite() const
</pre>

Returns true if both <a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_fY">fY</a> are measurable values.

### Return Value

true for values other than infinities and NaN

### Example

<div><fiddle-embed name="937cc166cc0e220f33fb82501141d0b3">

#### Example Output

~~~~
pt: 0, -0  finite: true
pt: -1, -2  finite: true
pt: inf, 1  finite: false
pt: nan, -1  finite: false
~~~~

</fiddle-embed></div>

### See Also

<a href="SkRect_Reference#SkRect_isFinite">SkRect::isFinite</a> <a href="SkPath_Reference#SkPath_isFinite">SkPath::isFinite</a>

---

<a name="SkPoint_equals"></a>
## equals

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool equals(SkScalar x, SkScalar y) const
</pre>

Returns true if <a href="#Point">Point</a> is equivalent to <a href="#Point">Point</a> constructed from (x, y).

### Parameters

<table>  <tr>    <td><a name="SkPoint_equals_x"> <code><strong>x </strong></code> </a></td> <td>
value compared with <a href="#SkPoint_fX">fX</a></td>
  </tr>  <tr>    <td><a name="SkPoint_equals_y"> <code><strong>y </strong></code> </a></td> <td>
value compared with <a href="#SkPoint_fY">fY</a></td>
  </tr>
</table>

### Return Value

true if <a href="#Point">Point</a> equals (x, y)

### Example

<div><fiddle-embed name="4cecb878c8b66beffda051f26c00f817">

#### Example Output

~~~~
pt: 0, -0  == pt
pt: -1, -2  == pt
pt: inf, 1  == pt
pt: nan, -1  != pt
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_equal_operator">operator==(const SkPoint& a, const SkPoint& b)</a>

---

<a name="SkPoint_equal_operator"></a>
## operator==

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool operator==(const SkPoint& a, const SkPoint& b)
</pre>

Returns true if <a href="#SkPoint_equal_operator_a">a</a> is equivalent to <a href="#SkPoint_equal_operator_b">b</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_equal_operator_a"> <code><strong>a </strong></code> </a></td> <td>
<a href="#Point">Point</a> to compare</td>
  </tr>  <tr>    <td><a name="SkPoint_equal_operator_b"> <code><strong>b </strong></code> </a></td> <td>
<a href="#Point">Point</a> to compare</td>
  </tr>
</table>

### Return Value

true if <a href="#SkPoint_equal_operator_a">a</a>.<a href="#SkPoint_fX">fX</a> == <a href="#SkPoint_equal_operator_b">b</a>.<a href="#SkPoint_fX">fX</a> and <a href="#SkPoint_equal_operator_a">a</a>.<a href="#SkPoint_fY">fY</a> == <a href="#SkPoint_equal_operator_b">b</a>.<a href="#SkPoint_fY">fY</a>

### Example

<div><fiddle-embed name="741f793334a48a35dadf4310d7ea52cb">

#### Example Output

~~~~
pt: 0, -0  == pt
pt: -1, -2  == pt
pt: inf, 1  == pt
pt: nan, -1  != pt
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_equals">equals</a> <a href="#SkPoint_notequal_operator">operator!=(const SkPoint& a, const SkPoint& b)</a>

---

<a name="SkPoint_notequal_operator"></a>
## operator!=

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool operator!=(const SkPoint& a, const SkPoint& b)
</pre>

Returns true if <a href="#SkPoint_notequal_operator_a">a</a> is not equivalent to <a href="#SkPoint_notequal_operator_b">b</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_notequal_operator_a"> <code><strong>a </strong></code> </a></td> <td>
<a href="#Point">Point</a> to compare</td>
  </tr>  <tr>    <td><a name="SkPoint_notequal_operator_b"> <code><strong>b </strong></code> </a></td> <td>
<a href="#Point">Point</a> to compare</td>
  </tr>
</table>

### Return Value

true if <a href="#SkPoint_notequal_operator_a">a</a>.<a href="#SkPoint_fX">fX</a> != <a href="#SkPoint_notequal_operator_b">b</a>.<a href="#SkPoint_fX">fX</a> or <a href="#SkPoint_notequal_operator_a">a</a>.<a href="#SkPoint_fY">fY</a> != <a href="#SkPoint_notequal_operator_b">b</a>.<a href="#SkPoint_fY">fY</a>

### Example

<div><fiddle-embed name="8fe8572685eaa617f25a5a6767a874dc">

#### Example Output

~~~~
pt: 0, -0  == pt
pt: -1, -2  == pt
pt: inf, 1  == pt
pt: nan, -1  != pt
~~~~

</fiddle-embed></div>

### See Also

<a href="#SkPoint_equal_operator">operator==(const SkPoint& a, const SkPoint& b)</a> <a href="#SkPoint_equals">equals</a>

---

<a name="SkPoint_subtract_operator"></a>
## operator-

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkVector operator-(const SkPoint& a, const SkPoint& b)
</pre>

Returns <a href="#Vector">Vector</a> from <a href="#SkPoint_subtract_operator_b">b</a> to <a href="#SkPoint_subtract_operator_a">a</a>, computed as(<a href="#SkPoint_subtract_operator_a">a</a>.<a href="#SkPoint_fX">fX</a> - <a href="#SkPoint_subtract_operator_b">b</a>.<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_subtract_operator_a">a</a>.<a href="#SkPoint_fY">fY</a> - <a href="#SkPoint_subtract_operator_b">b</a>.<a href="#SkPoint_fY">fY</a>).

Can also be used to subtract <a href="#Vector">Vector</a> from <a href="#Point">Point</a>, returning <a href="#Point">Point</a>.
Can also be used to subtract <a href="#Vector">Vector</a> from <a href="#Vector">Vector</a>, returning <a href="#Vector">Vector</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_subtract_operator_a"> <code><strong>a </strong></code> </a></td> <td>
<a href="#Point">Point</a> to subtract from</td>
  </tr>  <tr>    <td><a name="SkPoint_subtract_operator_b"> <code><strong>b </strong></code> </a></td> <td>
<a href="#Point">Point</a> to subtract</td>
  </tr>
</table>

### Return Value

<a href="#Vector">Vector</a> from <a href="#SkPoint_subtract_operator_b">b</a> to <a href="#SkPoint_subtract_operator_a">a</a>

### Example

<div><fiddle-embed name="b6c4943ecd0b2dccf9d220b8944009e0"></fiddle-embed></div>

### See Also

<a href="#SkPoint_subtractfrom_operator">operator-=(const SkVector& v)</a> <a href="#SkPoint_offset">offset</a>

---

<a name="SkPoint_add_operator"></a>
## operator+

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkPoint operator+(const SkPoint& a, const SkVector& b)
</pre>

Returns <a href="#Point">Point</a> resulting from <a href="#Point">Point</a> <a href="#SkPoint_add_operator_a">a</a> offset by <a href="#Vector">Vector</a> <a href="#SkPoint_add_operator_b">b</a>, computed as:
(<a href="#SkPoint_add_operator_a">a</a>.<a href="#SkPoint_fX">fX</a> + <a href="#SkPoint_add_operator_b">b</a>.<a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_add_operator_a">a</a>.<a href="#SkPoint_fY">fY</a> + <a href="#SkPoint_add_operator_b">b</a>.<a href="#SkPoint_fY">fY</a>).

Can also be used to offset <a href="#Point">Point</a> <a href="#SkPoint_add_operator_b">b</a> by <a href="#Vector">Vector</a> <a href="#SkPoint_add_operator_a">a</a>, returning <a href="#Point">Point</a>.
Can also be used to add <a href="#Vector">Vector</a> to <a href="#Vector">Vector</a>, returning <a href="#Vector">Vector</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_add_operator_a"> <code><strong>a </strong></code> </a></td> <td>
<a href="#Point">Point</a> or <a href="#Vector">Vector</a> to add to</td>
  </tr>  <tr>    <td><a name="SkPoint_add_operator_b"> <code><strong>b </strong></code> </a></td> <td>
<a href="#Point">Point</a> or <a href="#Vector">Vector</a> to add</td>
  </tr>
</table>

### Return Value

<a href="#Point">Point</a> equal to <a href="#SkPoint_add_operator_a">a</a> offset by <a href="#SkPoint_add_operator_b">b</a>

### Example

<div><fiddle-embed name="911a84253dfec4dabf94dbe3c71766f0"></fiddle-embed></div>

### See Also

<a href="#SkPoint_addto_operator">operator+=(const SkVector& v)</a> <a href="#SkPoint_offset">offset</a>

---

<a name="SkPoint_Length"></a>
## Length

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static SkScalar Length(SkScalar x, SkScalar y)
</pre>

Returns the Euclidean_Distance from origin, computed as:

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
sqrt(x * x + y * y)</pre>

.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Length_x"> <code><strong>x </strong></code> </a></td> <td>
component of length</td>
  </tr>  <tr>    <td><a name="SkPoint_Length_y"> <code><strong>y </strong></code> </a></td> <td>
component of length</td>
  </tr>
</table>

### Return Value

straight-line distance to origin

### Example

<div><fiddle-embed name="c98773d8b4509969d78cb8121e4b77f6"></fiddle-embed></div>

### See Also

<a href="#SkPoint_length">length</a> <a href="#SkPoint_Distance">Distance</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup>

---

<a name="SkPoint_Normalize"></a>
## Normalize

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static SkScalar Normalize(SkVector* vec)
</pre>

Scales (<a href="#SkPoint_Normalize_vec">vec</a>-><a href="#SkPoint_fX">fX</a>, <a href="#SkPoint_Normalize_vec">vec</a>-><a href="#SkPoint_fY">fY</a>) so that <a href="#SkPoint_length">length</a> returns one, while preserving ratio of <a href="#SkPoint_Normalize_vec">vec</a>-><a href="#SkPoint_fX">fX</a> to <a href="#SkPoint_Normalize_vec">vec</a>-><a href="#SkPoint_fY">fY</a>,
if possible. If original length is nearly zero, sets <a href="#SkPoint_Normalize_vec">vec</a> to (0, 0) and returns zero;
otherwise, returns length of <a href="#SkPoint_Normalize_vec">vec</a> before <a href="#SkPoint_Normalize_vec">vec</a> is scaled.

Returned prior length may be <a href="undocumented#SK_ScalarInfinity">SK ScalarInfinity</a> if it can not be represented by <a href="undocumented#SkScalar">SkScalar</a>.

Note that <a href="#SkPoint_normalize">normalize</a> is faster if prior length is not required.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Normalize_vec"> <code><strong>vec </strong></code> </a></td> <td>
normalized to unit length</td>
  </tr>
</table>

### Return Value

original <a href="#SkPoint_Normalize_vec">vec</a> length

### Example

<div><fiddle-embed name="60a08f3ce75374fc815384616d114df7"></fiddle-embed></div>

### See Also

<a href="#SkPoint_normalize">normalize</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup> <a href="#SkPoint_Length">Length</a>

---

<a name="SkPoint_Distance"></a>
## Distance

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static SkScalar Distance(const SkPoint& a, const SkPoint& b)
</pre>

Returns the Euclidean_Distance between <a href="#SkPoint_Distance_a">a</a> and <a href="#SkPoint_Distance_b">b</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_Distance_a"> <code><strong>a </strong></code> </a></td> <td>
line end point</td>
  </tr>  <tr>    <td><a name="SkPoint_Distance_b"> <code><strong>b </strong></code> </a></td> <td>
line end point</td>
  </tr>
</table>

### Return Value

straight-line distance from <a href="#SkPoint_Distance_a">a</a> to <a href="#SkPoint_Distance_b">b</a>

### Example

<div><fiddle-embed name="9e0a2de2eb94dba4521d733e73f2bda5"></fiddle-embed></div>

### See Also

<a href="#SkPoint_length">length</a> <a href="#SkPoint_setLength">setLength</a><sup><a href="#SkPoint_setLength_2">[2]</a></sup>

---

<a name="SkPoint_DotProduct"></a>
## DotProduct

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static SkScalar DotProduct(const SkVector& a, const SkVector& b)
</pre>

Returns the dot product of <a href="#Vector">Vector</a> <a href="#SkPoint_DotProduct_a">a</a> and <a href="#Vector">Vector</a> <a href="#SkPoint_DotProduct_b">b</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_DotProduct_a"> <code><strong>a </strong></code> </a></td> <td>
left side of dot product</td>
  </tr>  <tr>    <td><a name="SkPoint_DotProduct_b"> <code><strong>b </strong></code> </a></td> <td>
right side of dot product</td>
  </tr>
</table>

### Return Value

product of input magnitudes and cosine of the angle between them

### Example

<div><fiddle-embed name="496db0131a003162faba7d7f98b30340"></fiddle-embed></div>

### See Also

<a href="#SkPoint_dot">dot</a> <a href="#SkPoint_CrossProduct">CrossProduct</a>

---

<a name="SkPoint_CrossProduct"></a>
## CrossProduct

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static SkScalar CrossProduct(const SkVector& a, const SkVector& b)
</pre>

Returns the cross product of <a href="#Vector">Vector</a> <a href="#SkPoint_CrossProduct_a">a</a> and <a href="#Vector">Vector</a> <a href="#SkPoint_CrossProduct_b">b</a>.

<a href="#SkPoint_CrossProduct_a">a</a> and <a href="#SkPoint_CrossProduct_b">b</a> form three-dimensional vectors with z-axis value equal to zero. The
cross product is <a href="#SkPoint_CrossProduct_a">a</a> three-dimensional vector with x-axis and y-axis values equal
to zero. The cross product z-axis component is returned.

### Parameters

<table>  <tr>    <td><a name="SkPoint_CrossProduct_a"> <code><strong>a </strong></code> </a></td> <td>
left side of cross product</td>
  </tr>  <tr>    <td><a name="SkPoint_CrossProduct_b"> <code><strong>b </strong></code> </a></td> <td>
right side of cross product</td>
  </tr>
</table>

### Return Value

area spanned by <a href="#Vector">Vectors</a> signed by angle direction

### Example

<div><fiddle-embed name="8b8a4cd8a29d22bb9c5e63b70357bd65"></fiddle-embed></div>

### See Also

<a href="#SkPoint_cross">cross</a> <a href="#SkPoint_DotProduct">DotProduct</a>

---

<a name="SkPoint_cross"></a>
## cross

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar cross(const SkVector& vec) const
</pre>

Returns the cross product of <a href="#Vector">Vector</a> and <a href="#SkPoint_cross_vec">vec</a>.

<a href="#Vector">Vector</a> and <a href="#SkPoint_cross_vec">vec</a> form three-dimensional vectors with z-axis value equal to zero.
The cross product is a three-dimensional vector with x-axis and y-axis values
equal to zero. The cross product z-axis component is returned.

### Parameters

<table>  <tr>    <td><a name="SkPoint_cross_vec"> <code><strong>vec </strong></code> </a></td> <td>
right side of cross product</td>
  </tr>
</table>

### Return Value

area spanned by <a href="#Vector">Vectors</a> signed by angle direction

### Example

<div><fiddle-embed name="0bc7b3997357e499817278b78bdfbf1d"></fiddle-embed></div>

### See Also

<a href="#SkPoint_CrossProduct">CrossProduct</a> <a href="#SkPoint_dot">dot</a>

---

<a name="SkPoint_dot"></a>
## dot

<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkScalar dot(const SkVector& vec) const
</pre>

Returns the dot product of <a href="#Vector">Vector</a> and <a href="#Vector">Vector</a> <a href="#SkPoint_dot_vec">vec</a>.

### Parameters

<table>  <tr>    <td><a name="SkPoint_dot_vec"> <code><strong>vec </strong></code> </a></td> <td>
right side of dot product</td>
  </tr>
</table>

### Return Value

product of input magnitudes and cosine of the angle between them

### Example

<div><fiddle-embed name="56d01ccfedd71d3c504b09afa2875d38"></fiddle-embed></div>

### See Also

<a href="#SkPoint_DotProduct">DotProduct</a> <a href="#SkPoint_cross">cross</a>

---

# <a name="Vector"></a> Vector