skia2/site/user/api/SkSurface_Reference.md
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SkSurface Reference
===
# <a name="Surface"></a> Surface
# <a name="SkSurface"></a> Class SkSurface
<a href="#SkSurface">SkSurface</a> is responsible for managing the pixels that a canvas draws into. The pixels can be
allocated either in CPU memory (a raster surface) or on the GPU (a <a href="undocumented#GrRenderTarget">GrRenderTarget</a> surface).
<a href="#SkSurface">SkSurface</a> takes care of allocating a <a href="SkCanvas_Reference#SkCanvas">SkCanvas</a> that will <a href="#SkSurface_draw">draw</a> into the surface. Call
surface-><a href="#SkSurface_getCanvas">getCanvas</a> to use that canvas (but don't delete it, it is owned by the surface).
<a href="#SkSurface">SkSurface</a> always has non-zero dimensions. If there is a request for a new surface, and either
of the requested dimensions are zero, then nullptr will be returned.
# <a name="Overview"></a> Overview
## <a name="Subtopics"></a> Subtopics
| topics | description |
| --- | --- |
| <a href="#Overview_Constructors">Constructors</a> | functions that construct <a href="SkIPoint16_Reference#SkIPoint16">SkIPoint16</a> |
| <a href="#Overview_Member_Functions">Member Functions</a> | static functions and member methods |
## <a name="Constructors"></a> Constructors
| name | description |
| --- | --- |
| <a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> | creates <a href="#Surface">Surface</a> from GPU memory buffer |
| <a href="#SkSurface_MakeFromBackendTexture">MakeFromBackendTexture</a> | creates <a href="#Surface">Surface</a> from GPU-backed texture |
| <a href="#SkSurface_MakeFromBackendTextureAsRenderTarget">MakeFromBackendTextureAsRenderTarget</a> | creates <a href="#Surface">Surface</a> from GPU-backed texture |
| <a href="#SkSurface_MakeNull">MakeNull</a> | creates <a href="#Surface">Surface</a> without backing pixels |
| <a href="#SkSurface_MakeRaster">MakeRaster</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> |
| <a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> and <a href="#Storage">Pixel Storage</a> |
| <a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> and <a href="#Storage">Pixel Storage</a> |
| <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> | creates <a href="#Surface">Surface</a> from <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a> matching output |
| <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a> | creates <a href="#Surface">Surface</a> pointing to new GPU memory buffer |
| <a href="#SkCanvas_makeSurface">SkCanvas::makeSurface</a> | creates <a href="#Surface">Surface</a> matching <a href="SkCanvas_Reference#Canvas">Canvas</a> <a href="undocumented#Image_Info">Image Info</a>, <a href="#Properties">Surface Properties</a> |
| <a href="#SkSurface_makeSurface">makeSurface</a> | creates a compatible <a href="#Surface">Surface</a> |
## <a name="Member_Functions"></a> Member Functions
| description | function |
| --- | --- |
| <a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> | creates <a href="#Surface">Surface</a> from GPU memory buffer |
| <a href="#SkSurface_MakeFromBackendTexture">MakeFromBackendTexture</a> | creates <a href="#Surface">Surface</a> from GPU-backed texture |
| <a href="#SkSurface_MakeFromBackendTextureAsRenderTarget">MakeFromBackendTextureAsRenderTarget</a> | creates <a href="#Surface">Surface</a> from GPU-backed texture |
| <a href="#SkSurface_MakeNull">MakeNull</a> | creates <a href="#Surface">Surface</a> without backing pixels |
| <a href="#SkSurface_MakeRaster">MakeRaster</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> |
| <a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> and <a href="#Storage">Pixel Storage</a> |
| <a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a> | creates <a href="#Surface">Surface</a> from <a href="undocumented#SkImageInfo">SkImageInfo</a> and <a href="#Storage">Pixel Storage</a> |
| <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> | creates <a href="#Surface">Surface</a> from <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a> matching output |
| <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a> | creates <a href="#Surface">Surface</a> pointing to new GPU memory buffer |
| <a href="#SkSurface_characterize">characterize</a> | sets <a href="#Characterization">Surface Characterization</a> for threaded pre-processing |
| <a href="#SkSurface_draw">draw</a> | draws <a href="#Surface">Surface</a> contents to canvas |
| <a href="#SkSurface_flush">flush</a> | resolve pending I/O |
| <a href="#SkSurface_flushAndSignalSemaphores">flushAndSignalSemaphores</a> | resolve pending I/O, and signal |
| <a href="#SkSurface_generationID">generationID</a> | returns unique ID |
| <a href="#SkSurface_getCanvas">getCanvas</a> | returns <a href="SkCanvas_Reference#Canvas">Canvas</a> that draws into <a href="#Surface">Surface</a> |
| <a href="#SkSurface_getRenderTargetHandle">getRenderTargetHandle</a> | returns the GPU reference to render target |
| <a href="#SkSurface_getTextureHandle">getTextureHandle</a> | returns the GPU reference to texture |
| <a href="#SkSurface_height">height</a> | returns pixel row count |
| <a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> | creates <a href="SkImage_Reference#Image">Image</a> capturing <a href="#Surface">Surface</a> contents |
| <a href="#SkSurface_makeSurface">makeSurface</a> | creates a compatible <a href="#Surface">Surface</a> |
| <a href="#SkSurface_notifyContentWillChange">notifyContentWillChange</a> | notifies that contents will be changed outside of Skia |
| <a href="#SkSurface_peekPixels">peekPixels</a> | copies <a href="#Surface">Surface</a> parameters to <a href="SkPixmap_Reference#Pixmap">Pixmap</a> |
| <a href="#SkSurface_prepareForExternalIO">prepareForExternalIO</a> | to be deprecated |
| <a href="#SkSurface_props">props</a> | returns <a href="#Properties">Surface Properties</a> |
| <a href="#SkSurface_readPixels">readPixels</a> | copies <a href="SkRect_Reference#Rect">Rect</a> of pixels |
| <a href="#SkSurface_wait">wait</a> | rause commands until signaled |
| <a href="#SkSurface_width">width</a> | returns pixel column count |
<a name="SkSurface_MakeRasterDirect"></a>
## MakeRasterDirect
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRasterDirect(const SkImageInfo& imageInfo, void* pixels, size_t rowBytes,
const SkSurfaceProps* surfaceProps = nullptr)
</pre>
Allocates raster <a href="#Surface">Surface</a>. <a href="SkCanvas_Reference#Canvas">Canvas</a> returned by <a href="#Surface">Surface</a> draws directly into <a href="#SkSurface_MakeRasterDirect_pixels">pixels</a>.
<a href="#Surface">Surface</a> is returned if all parameters are valid.
Valid parameters include:
info dimensions are greater than zero;
info contains <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a> supported by <a href="undocumented#Raster_Surface">Raster Surface</a>;
<a href="#SkSurface_MakeRasterDirect_pixels">pixels</a> is not nullptr;
<a href="#SkSurface_MakeRasterDirect_rowBytes">rowBytes</a> is large enough to contain info <a href="#SkSurface_width">width</a> <a href="#SkSurface_MakeRasterDirect_pixels">pixels</a> of <a href="undocumented#Image_Color_Type">Image Color Type</a>.
<a href="undocumented#Pixel">Pixel</a> buffer size should be info <a href="#SkSurface_height">height</a> times computed <a href="#SkSurface_MakeRasterDirect_rowBytes">rowBytes</a>.
Pixels are not initialized.
To access <a href="#SkSurface_MakeRasterDirect_pixels">pixels</a> after drawing, call <a href="#SkSurface_flush">flush</a> or <a href="#SkSurface_peekPixels">peekPixels</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRasterDirect_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirect_pixels"> <code><strong>pixels </strong></code> </a></td> <td>
pointer to destination <a href="#SkSurface_MakeRasterDirect_pixels">pixels</a> buffer</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirect_rowBytes"> <code><strong>rowBytes </strong></code> </a></td> <td>
interval from one <a href="#Surface">Surface</a> row to the next</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirect_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent fonts;
may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="3f5aeb870104187643197354a7f1d27a">
#### Example Output
~~~~
---
-x-
---
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a> <a href="#SkSurface_MakeRaster">MakeRaster</a> <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> <a href="#SkCanvas_MakeRasterDirect">SkCanvas::MakeRasterDirect</a>
---
<a name="SkSurface_MakeRasterDirectReleaseProc"></a>
## MakeRasterDirectReleaseProc
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRasterDirectReleaseProc(const SkImageInfo& imageInfo, void* pixels,
size_t rowBytes, void (*releaseProc) (void* pixels,
void* context) , void* context,
const SkSurfaceProps* surfaceProps = nullptr)
</pre>
Allocates raster <a href="#Surface">Surface</a>. <a href="SkCanvas_Reference#Canvas">Canvas</a> returned by <a href="#Surface">Surface</a> draws directly into <a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a>.
<a href="#SkSurface_MakeRasterDirectReleaseProc_releaseProc">releaseProc</a> is called with <a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a> and <a href="#SkSurface_MakeRasterDirectReleaseProc_context">context</a> when <a href="#Surface">Surface</a> is deleted.
<a href="#Surface">Surface</a> is returned if all parameters are valid.
Valid parameters include:
info dimensions are greater than zero;
info contains <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a> supported by <a href="undocumented#Raster_Surface">Raster Surface</a>;
<a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a> is not nullptr;
<a href="#SkSurface_MakeRasterDirectReleaseProc_rowBytes">rowBytes</a> is large enough to contain info <a href="#SkSurface_width">width</a> <a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a> of <a href="undocumented#Image_Color_Type">Image Color Type</a>.
<a href="undocumented#Pixel">Pixel</a> buffer size should be info <a href="#SkSurface_height">height</a> times computed <a href="#SkSurface_MakeRasterDirectReleaseProc_rowBytes">rowBytes</a>.
Pixels are not initialized.
To access <a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a> after drawing, call <a href="#SkSurface_flush">flush</a> or <a href="#SkSurface_peekPixels">peekPixels</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_pixels"> <code><strong>pixels </strong></code> </a></td> <td>
pointer to destination <a href="#SkSurface_MakeRasterDirectReleaseProc_pixels">pixels</a> buffer</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_rowBytes"> <code><strong>rowBytes </strong></code> </a></td> <td>
interval from one <a href="#Surface">Surface</a> row to the next</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_releaseProc"> <code><strong>releaseProc </strong></code> </a></td> <td>
called when <a href="#Surface">Surface</a> is deleted; may be nullptr</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_context"> <code><strong>context </strong></code> </a></td> <td>
passed to <a href="#SkSurface_MakeRasterDirectReleaseProc_releaseProc">releaseProc</a>; may be nullptr</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterDirectReleaseProc_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent fonts;
may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="8e6530b26ab4096a9a91cfaadda1c568">
#### Example Output
~~~~
---
-x-
---
expected release context
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> <a href="#SkSurface_MakeRaster">MakeRaster</a>
---
<a name="SkSurface_MakeRaster"></a>
## MakeRaster
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRaster(const SkImageInfo& imageInfo, size_t rowBytes,
const SkSurfaceProps* surfaceProps)
</pre>
Allocates raster <a href="#Surface">Surface</a>. <a href="SkCanvas_Reference#Canvas">Canvas</a> returned by <a href="#Surface">Surface</a> draws directly into pixels.
Allocates and zeroes pixel memory. <a href="undocumented#Pixel">Pixel</a> memory size is <a href="#SkSurface_MakeRaster_imageInfo">imageInfo</a>.<a href="#SkSurface_height">height</a> times
<a href="#SkSurface_MakeRaster_rowBytes">rowBytes</a>, or times <a href="#SkSurface_MakeRaster_imageInfo">imageInfo</a>.minRowBytes() if <a href="#SkSurface_MakeRaster_rowBytes">rowBytes</a> is zero.
<a href="undocumented#Pixel">Pixel</a> memory is deleted when <a href="#Surface">Surface</a> is deleted.
<a href="#Surface">Surface</a> is returned if all parameters are valid.
Valid parameters include:
info dimensions are greater than zero;
info contains <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a> supported by <a href="undocumented#Raster_Surface">Raster Surface</a>;
<a href="#SkSurface_MakeRaster_rowBytes">rowBytes</a> is large enough to contain info <a href="#SkSurface_width">width</a> pixels of <a href="undocumented#Image_Color_Type">Image Color Type</a>, or is zero.
If <a href="#SkSurface_MakeRaster_rowBytes">rowBytes</a> is not zero, subsequent images returned by <a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a>
have the same <a href="#SkSurface_MakeRaster_rowBytes">rowBytes</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRaster_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRaster_rowBytes"> <code><strong>rowBytes </strong></code> </a></td> <td>
interval from one <a href="#Surface">Surface</a> row to the next; may be zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRaster_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent fonts;
may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="a803910ada4f8733f0b62456afead55f">
#### Example Output
~~~~
---
-x-
---
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> <a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRaster(const SkImageInfo& imageInfo,
const SkSurfaceProps* props = nullptr)
</pre>
Allocates raster <a href="#Surface">Surface</a>. <a href="SkCanvas_Reference#Canvas">Canvas</a> returned by <a href="#Surface">Surface</a> draws directly into pixels.
Allocates and zeroes pixel memory. <a href="undocumented#Pixel">Pixel</a> memory size is <a href="#SkSurface_MakeRaster_2_imageInfo">imageInfo</a>.<a href="#SkSurface_height">height</a> times
<a href="#SkSurface_MakeRaster_2_imageInfo">imageInfo</a>.minRowBytes().
<a href="undocumented#Pixel">Pixel</a> memory is deleted when <a href="#Surface">Surface</a> is deleted.
<a href="#Surface">Surface</a> is returned if all parameters are valid.
Valid parameters include:
info dimensions are greater than zero;
info contains <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a> supported by <a href="undocumented#Raster_Surface">Raster Surface</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRaster_2_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRaster_2_props"> <code><strong>props </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent fonts;
may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="c6197d204ef9e4ccfb583242651fb2a7"></fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> <a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a>
---
<a name="SkSurface_MakeRasterN32Premul"></a>
## MakeRasterN32Premul
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRasterN32Premul(int width, int height,
const SkSurfaceProps* surfaceProps = nullptr)
</pre>
Allocates raster <a href="#Surface">Surface</a>. <a href="SkCanvas_Reference#Canvas">Canvas</a> returned by <a href="#Surface">Surface</a> draws directly into pixels.
Allocates and zeroes pixel memory. <a href="undocumented#Pixel">Pixel</a> memory size is <a href="#SkSurface_height">height</a> times <a href="#SkSurface_width">width</a> times
four. <a href="undocumented#Pixel">Pixel</a> memory is deleted when <a href="#Surface">Surface</a> is deleted.
Internally, sets <a href="undocumented#Image_Info">Image Info</a> to <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Native_Color_Type">Native Color Type</a>, and
<a href="undocumented#SkAlphaType">kPremul SkAlphaType</a>.
<a href="#Surface">Surface</a> is returned if <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> are greater than zero.
Use to create <a href="#Surface">Surface</a> that matches <a href="undocumented#SkPMColor">SkPMColor</a>, the native pixel arrangement on
the platform. <a href="#Surface">Surface</a> drawn to output device skips converting its pixel format.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRasterN32Premul_width"> <code><strong>width </strong></code> </a></td> <td>
pixel column count; must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterN32Premul_height"> <code><strong>height </strong></code> </a></td> <td>
pixel row count; must be greater than zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRasterN32Premul_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="b932a2bd68455fb0af2e7a1ed19e36b3">
#### Example Output
~~~~
---
-x-
---
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRasterDirect">MakeRasterDirect</a> <a href="#SkSurface_MakeRasterN32Premul">MakeRasterN32Premul</a> <a href="#SkSurface_MakeRasterDirectReleaseProc">MakeRasterDirectReleaseProc</a>
---
<a name="SkSurface_MakeFromBackendTexture"></a>
## MakeFromBackendTexture
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendTexture(GrContext* context,
const GrBackendTexture& backendTexture,
GrSurfaceOrigin origin, int sampleCnt,
sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Wraps a GPU-backed texture into <a href="#Surface">Surface</a>. Caller must ensure the texture is
valid for the lifetime of returned <a href="#Surface">Surface</a>. If <a href="#SkSurface_MakeFromBackendTexture_sampleCnt">sampleCnt</a> greater than zero,
creates an intermediate MSAA <a href="#Surface">Surface</a> which is used for drawing <a href="#SkSurface_MakeFromBackendTexture_backendTexture">backendTexture</a>.
<a href="#Surface">Surface</a> is returned if all parameters are valid. <a href="#SkSurface_MakeFromBackendTexture_backendTexture">backendTexture</a> is valid if
its pixel configuration agrees with <a href="#SkSurface_MakeFromBackendTexture_colorSpace">colorSpace</a> and <a href="#SkSurface_MakeFromBackendTexture_context">context</a>; for instance, if
<a href="#SkSurface_MakeFromBackendTexture_backendTexture">backendTexture</a> has an sRGB configuration, then <a href="#SkSurface_MakeFromBackendTexture_context">context</a> must support sRGB,
and <a href="#SkSurface_MakeFromBackendTexture_colorSpace">colorSpace</a> must be present. Further, <a href="#SkSurface_MakeFromBackendTexture_backendTexture">backendTexture</a> <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must
not exceed <a href="#SkSurface_MakeFromBackendTexture_context">context</a> capabilities, and the <a href="#SkSurface_MakeFromBackendTexture_context">context</a> must be able to support
back-end textures.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendTexture_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_backendTexture"> <code><strong>backendTexture </strong></code> </a></td> <td>
texture residing on GPU</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_sampleCnt"> <code><strong>sampleCnt </strong></code> </a></td> <td>
samples per pixel, or 0 to disable full scene anti-aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {
SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendTexture(context,
backEndTextureRenderTarget, kTopLeft_GrSurfaceOrigin, 0, nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="undocumented#GrBackendTexture">GrBackendTexture</a> <a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendTexture(GrContext* context,
const GrBackendTexture& backendTexture,
GrSurfaceOrigin origin, int sampleCnt,
SkColorType colorType,
sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Wraps a GPU-backed texture into <a href="#Surface">Surface</a>. Caller must ensure the texture is
valid for the lifetime of returned <a href="#Surface">Surface</a>. If <a href="#SkSurface_MakeFromBackendTexture_2_sampleCnt">sampleCnt</a> greater than zero,
creates an intermediate MSAA <a href="#Surface">Surface</a> which is used for drawing <a href="#SkSurface_MakeFromBackendTexture_2_backendTexture">backendTexture</a>.
<a href="#Surface">Surface</a> is returned if all parameters are valid. <a href="#SkSurface_MakeFromBackendTexture_2_backendTexture">backendTexture</a> is valid if
its pixel configuration agrees with <a href="#SkSurface_MakeFromBackendTexture_2_colorSpace">colorSpace</a> and <a href="#SkSurface_MakeFromBackendTexture_2_context">context</a>; for instance, if
<a href="#SkSurface_MakeFromBackendTexture_2_backendTexture">backendTexture</a> has an sRGB configuration, then <a href="#SkSurface_MakeFromBackendTexture_2_context">context</a> must support sRGB,
and <a href="#SkSurface_MakeFromBackendTexture_2_colorSpace">colorSpace</a> must be present. Further, <a href="#SkSurface_MakeFromBackendTexture_2_backendTexture">backendTexture</a> <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must
not exceed <a href="#SkSurface_MakeFromBackendTexture_2_context">context</a> capabilities, and the <a href="#SkSurface_MakeFromBackendTexture_2_context">context</a> must be able to support
back-end textures.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_backendTexture"> <code><strong>backendTexture </strong></code> </a></td> <td>
texture residing on GPU</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_sampleCnt"> <code><strong>sampleCnt </strong></code> </a></td> <td>
samples per pixel, or 0 to disable full scene anti-aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_colorType"> <code><strong>colorType </strong></code> </a></td> <td>
one of: <a href="undocumented#SkColorType">kUnknown SkColorType</a>, <a href="undocumented#SkColorType">kAlpha 8 SkColorType</a>,
<a href="undocumented#SkColorType">kRGB 565 SkColorType</a>, <a href="undocumented#SkColorType">kARGB 4444 SkColorType</a>,
<a href="undocumented#SkColorType">kRGBA 8888 SkColorType</a>, <a href="undocumented#SkColorType">kBGRA 8888 SkColorType</a>,
<a href="undocumented#SkColorType">kGray 8 SkColorType</a>, <a href="undocumented#SkColorType">kRGBA F16 SkColorType</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTexture_2_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {
SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendTexture(context,
backEndTextureRenderTarget, kTopLeft_GrSurfaceOrigin,
kRGBA_8888_SkColorType, 0, nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="undocumented#GrBackendTexture">GrBackendTexture</a> <a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<a name="SkSurface_MakeFromBackendRenderTarget"></a>
## MakeFromBackendRenderTarget
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendRenderTarget(GrContext* context,
const GrBackendRenderTarget& backendRenderTarget,
GrSurfaceOrigin origin,
sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Wraps a GPU-backed buffer into <a href="#Surface">Surface</a>. Caller must ensure render target is
valid for the lifetime of returned <a href="#Surface">Surface</a>.
<a href="#Surface">Surface</a> is returned if all parameters are valid. <a href="#SkSurface_MakeFromBackendRenderTarget_backendRenderTarget">backendRenderTarget</a> is valid if
its pixel configuration agrees with <a href="#SkSurface_MakeFromBackendRenderTarget_colorSpace">colorSpace</a> and <a href="#SkSurface_MakeFromBackendRenderTarget_context">context</a>; for instance, if
<a href="#SkSurface_MakeFromBackendRenderTarget_backendRenderTarget">backendRenderTarget</a> has an sRGB configuration, then <a href="#SkSurface_MakeFromBackendRenderTarget_context">context</a> must support sRGB,
and <a href="#SkSurface_MakeFromBackendRenderTarget_colorSpace">colorSpace</a> must be present. Further, <a href="#SkSurface_MakeFromBackendRenderTarget_backendRenderTarget">backendRenderTarget</a> <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must
not exceed <a href="#SkSurface_MakeFromBackendRenderTarget_context">context</a> capabilities, and the <a href="#SkSurface_MakeFromBackendRenderTarget_context">context</a> must be able to support
back-end render targets.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_backendRenderTarget"> <code><strong>backendRenderTarget </strong></code> </a></td> <td>
GPU intermediate memory buffer</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {
SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendRenderTarget(context,
backEndRenderTarget, kTopLeft_GrSurfaceOrigin, nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="#SkSurface_MakeFromBackendTexture">MakeFromBackendTexture</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendRenderTarget(GrContext* context,
const GrBackendRenderTarget& backendRenderTarget,
GrSurfaceOrigin origin, SkColorType colorType,
sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Wraps a GPU-backed buffer into <a href="#Surface">Surface</a>. Caller must ensure render target is
valid for the lifetime of returned <a href="#Surface">Surface</a>.
<a href="#Surface">Surface</a> is returned if all parameters are valid. <a href="#SkSurface_MakeFromBackendRenderTarget_2_backendRenderTarget">backendRenderTarget</a> is valid if
its pixel configuration agrees with <a href="#SkSurface_MakeFromBackendRenderTarget_2_colorSpace">colorSpace</a> and <a href="#SkSurface_MakeFromBackendRenderTarget_2_context">context</a>; for instance, if
<a href="#SkSurface_MakeFromBackendRenderTarget_2_backendRenderTarget">backendRenderTarget</a> has an sRGB configuration, then <a href="#SkSurface_MakeFromBackendRenderTarget_2_context">context</a> must support sRGB,
and <a href="#SkSurface_MakeFromBackendRenderTarget_2_colorSpace">colorSpace</a> must be present. Further, <a href="#SkSurface_MakeFromBackendRenderTarget_2_backendRenderTarget">backendRenderTarget</a> <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must
not exceed <a href="#SkSurface_MakeFromBackendRenderTarget_2_context">context</a> capabilities, and the <a href="#SkSurface_MakeFromBackendRenderTarget_2_context">context</a> must be able to support
back-end render targets.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_backendRenderTarget"> <code><strong>backendRenderTarget </strong></code> </a></td> <td>
GPU intermediate memory buffer</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_colorType"> <code><strong>colorType </strong></code> </a></td> <td>
one of: <a href="undocumented#SkColorType">kUnknown SkColorType</a>, <a href="undocumented#SkColorType">kAlpha 8 SkColorType</a>,
<a href="undocumented#SkColorType">kRGB 565 SkColorType</a>, <a href="undocumented#SkColorType">kARGB 4444 SkColorType</a>,
<a href="undocumented#SkColorType">kRGBA 8888 SkColorType</a>, <a href="undocumented#SkColorType">kBGRA 8888 SkColorType</a>,
<a href="undocumented#SkColorType">kGray 8 SkColorType</a>, <a href="undocumented#SkColorType">kRGBA F16 SkColorType</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendRenderTarget_2_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {
SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendRenderTarget(context,
backEndRenderTarget, kTopLeft_GrSurfaceOrigin, kRGBA_8888_SkColorType,
nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="#SkSurface_MakeFromBackendTexture">MakeFromBackendTexture</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<a name="SkSurface_MakeFromBackendTextureAsRenderTarget"></a>
## MakeFromBackendTextureAsRenderTarget
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendTextureAsRenderTarget(GrContext* context,
const GrBackendTexture& backendTexture,
GrSurfaceOrigin origin, int sampleCnt,
sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Used to wrap a GPU-backed texture as a <a href="#SkSurface">SkSurface</a>. Skia will treat the texture as
a rendering target only, but unlike NewFromBackendRenderTarget, Skia will manage and own
the associated render target objects (but not the provided texture). Skia will not assume
ownership of the texture and the client must ensure the texture is valid for the lifetime
of the <a href="#SkSurface">SkSurface</a>.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_backendTexture"> <code><strong>backendTexture </strong></code> </a></td> <td>
texture residing on GPU</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_sampleCnt"> <code><strong>sampleCnt </strong></code> </a></td> <td>
samples per pixel, or 0 to disable full scene anti-aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendTextureAsRenderTarget(
context, backEndTextureRenderTarget, kTopLeft_GrSurfaceOrigin, 0,
nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeFromBackendTextureAsRenderTarget(GrContext* context,
const GrBackendTexture& backendTexture,
GrSurfaceOrigin origin, int sampleCnt,
SkColorType colorType, sk_sp&lt;SkColorSpace&gt; colorSpace,
const SkSurfaceProps* surfaceProps)
</pre>
Used to wrap a GPU-backed texture as a <a href="#SkSurface">SkSurface</a>. Skia will treat the texture as
a rendering target only, but unlike NewFromBackendRenderTarget, Skia will manage and own
the associated render target objects (but not the provided texture). Skia will not assume
ownership of the texture and the client must ensure the texture is valid for the lifetime
of the <a href="#SkSurface">SkSurface</a>.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_backendTexture"> <code><strong>backendTexture </strong></code> </a></td> <td>
texture residing on GPU</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_origin"> <code><strong>origin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_sampleCnt"> <code><strong>sampleCnt </strong></code> </a></td> <td>
samples per pixel, or 0 to disable full scene anti-aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_colorType"> <code><strong>colorType </strong></code> </a></td> <td>
one of: <a href="undocumented#SkColorType">kUnknown SkColorType</a>, <a href="undocumented#SkColorType">kAlpha 8 SkColorType</a>,
<a href="undocumented#SkColorType">kRGB 565 SkColorType</a>, <a href="undocumented#SkColorType">kARGB 4444 SkColorType</a>,
<a href="undocumented#SkColorType">kRGBA 8888 SkColorType</a>, <a href="undocumented#SkColorType">kBGRA 8888 SkColorType</a>,
<a href="undocumented#SkColorType">kGray 8 SkColorType</a>, <a href="undocumented#SkColorType">kRGBA F16 SkColorType</a></td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_colorSpace"> <code><strong>colorSpace </strong></code> </a></td> <td>
range of colors</td>
</tr> <tr> <td><a name="SkSurface_MakeFromBackendTextureAsRenderTarget_2_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<pre style="padding: 1em 1em 1em 1em; font-size: 13px width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas) {SkPaint paint;
paint.setTextSize(32);
GrContext* context = canvas->getGrContext();
if (!context) {
canvas->drawString("GPU only!", 20, 40, paint);
return;
}
sk_sp<SkSurface> gpuSurface = SkSurface::MakeFromBackendTextureAsRenderTarget(
context, backEndTextureRenderTarget, kTopLeft_GrSurfaceOrigin, 0,
kRGBA_8888_SkColorType, nullptr, nullptr);
auto surfaceCanvas = gpuSurface->getCanvas();
surfaceCanvas->clear(SK_ColorWHITE);
surfaceCanvas->drawString("GPU rocks!", 20, 40, paint);
sk_sp<SkImage> image(gpuSurface->makeImageSnapshot());
canvas->drawImage(image, 0, 0);
}
</pre>
### See Also
<a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<a name="SkSurface_MakeRenderTarget"></a>
## MakeRenderTarget
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRenderTarget(GrContext* context, SkBudgeted budgeted,
const SkImageInfo& imageInfo, int sampleCount,
GrSurfaceOrigin surfaceOrigin,
const SkSurfaceProps* surfaceProps,
bool shouldCreateWithMips = false)
</pre>
Returns offscreen <a href="#Surface">Surface</a> on GPU indicated by <a href="#SkSurface_MakeRenderTarget_context">context</a>. Allocates memory for
pixels, based on the <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, and <a href="undocumented#Image_Color_Type">Image Color Type</a> in ImageInfo. <a href="#SkSurface_MakeRenderTarget_budgeted">budgeted</a>
selects whether allocation for offscreen pixels is tracked by <a href="#SkSurface_MakeRenderTarget_context">context</a>. <a href="#SkSurface_MakeRenderTarget_imageInfo">imageInfo</a>
describes the pixel format in <a href="undocumented#Image_Color_Type">Image Color Type</a>, and transparency in
<a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, and color matching in <a href="undocumented#Color_Space">Color Space</a>.
<a href="#SkSurface_MakeRenderTarget_sampleCount">sampleCount</a> requests the number of samples per pixel.
Pass zero to disable Multi_Sample_Anti_Aliasing. The request is rounded
up to the next supported count, or rounded down if it is larger than the
maximum supported count.
<a href="#SkSurface_MakeRenderTarget_surfaceOrigin">surfaceOrigin</a> pins either the top-left or the bottom-left corner to the origin.
<a href="#SkSurface_MakeRenderTarget_shouldCreateWithMips">shouldCreateWithMips</a> hints that <a href="SkImage_Reference#Image">Image</a> returned by <a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> is <a href="undocumented#Mip_Map">Mip Map</a>.
If SK_SUPPORT_GPU is defined as zero, has no effect and returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRenderTarget_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_budgeted"> <code><strong>budgeted </strong></code> </a></td> <td>
one of: <a href="#SkBudgeted_kNo">SkBudgeted::kNo</a>, <a href="#SkBudgeted_kYes">SkBudgeted::kYes</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>;
<a href="#SkSurface_width">width</a>, or <a href="#SkSurface_height">height</a>, or both, may be zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_sampleCount"> <code><strong>sampleCount </strong></code> </a></td> <td>
samples per pixel, or 0 to disable full scene anti-aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_surfaceOrigin"> <code><strong>surfaceOrigin </strong></code> </a></td> <td>
one of: <a href="undocumented#GrSurfaceOrigin">kBottomLeft GrSurfaceOrigin</a>, <a href="undocumented#GrSurfaceOrigin">kTopLeft GrSurfaceOrigin</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_surfaceProps"> <code><strong>surfaceProps </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_shouldCreateWithMips"> <code><strong>shouldCreateWithMips </strong></code> </a></td> <td>
hint that <a href="#Surface">Surface</a> will host <a href="undocumented#Mip_Map">Mip Map</a> images</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="67b6609471a3f1ed0f4b1657004cdecb" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeFromBackendTextureAsRenderTarget">MakeFromBackendTextureAsRenderTarget</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRenderTarget(GrContext* context, SkBudgeted budgeted,
const SkImageInfo& imageInfo, int sampleCount,
const SkSurfaceProps* props)
</pre>
Returns offscreen <a href="#Surface">Surface</a> on GPU indicated by <a href="#SkSurface_MakeRenderTarget_2_context">context</a>. Allocates memory for
pixels, based on the <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, and <a href="undocumented#Image_Color_Type">Image Color Type</a> in ImageInfo. <a href="#SkSurface_MakeRenderTarget_2_budgeted">budgeted</a>
selects whether allocation for offscreen pixels is tracked by <a href="#SkSurface_MakeRenderTarget_2_context">context</a>. <a href="#SkSurface_MakeRenderTarget_2_imageInfo">imageInfo</a>
describes the pixel format in <a href="undocumented#Image_Color_Type">Image Color Type</a>, and transparency in
<a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, and color matching in <a href="undocumented#Color_Space">Color Space</a>.
<a href="#SkSurface_MakeRenderTarget_2_sampleCount">sampleCount</a> requests the number of samples per pixel.
Pass zero to disable Multi_Sample_Anti_Aliasing. The request is rounded
up to the next supported count, or rounded down if it is larger than the
maximum supported count.
<a href="#Surface">Surface</a> bottom-left corner is pinned to the origin.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRenderTarget_2_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_2_budgeted"> <code><strong>budgeted </strong></code> </a></td> <td>
one of: <a href="#SkBudgeted_kNo">SkBudgeted::kNo</a>, <a href="#SkBudgeted_kYes">SkBudgeted::kYes</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_2_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a>, or <a href="#SkSurface_height">height</a>, or both, may be zero</td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_2_sampleCount"> <code><strong>sampleCount </strong></code> </a></td> <td>
samples per pixel, or 0 to disable Multi_Sample_Anti_Aliasing</td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_2_props"> <code><strong>props </strong></code> </a></td> <td>
LCD striping orientation and setting for device independent
fonts; may be nullptr</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="640321e8ecfb3f9329f3bc6e1f02485f" gpu="true" cpu="true"><div>LCD text takes advantage of raster striping to improve resolution. Only one of
the four combinations is correct, depending on whether the monitor's LCD is
horizontal or vertical, and whether the order of the stripes is red blue green
or red green blue.</div></fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeFromBackendTextureAsRenderTarget">MakeFromBackendTextureAsRenderTarget</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeRenderTarget(GrContext* context, SkBudgeted budgeted,
const SkImageInfo& imageInfo)
</pre>
Returns offscreen <a href="#Surface">Surface</a> on GPU indicated by <a href="#SkSurface_MakeRenderTarget_3_context">context</a>. Allocates memory for
pixels, based on the <a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, and <a href="undocumented#Image_Color_Type">Image Color Type</a> in ImageInfo. <a href="#SkSurface_MakeRenderTarget_3_budgeted">budgeted</a>
selects whether allocation for offscreen pixels is tracked by <a href="#SkSurface_MakeRenderTarget_3_context">context</a>. <a href="#SkSurface_MakeRenderTarget_3_imageInfo">imageInfo</a>
describes the pixel format in <a href="undocumented#Image_Color_Type">Image Color Type</a>, and transparency in
<a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, and color matching in <a href="undocumented#Color_Space">Color Space</a>.
<a href="#Surface">Surface</a> bottom-left corner is pinned to the origin.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeRenderTarget_3_context"> <code><strong>context </strong></code> </a></td> <td>
<a href="undocumented#GPU_Context">GPU Context</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_3_budgeted"> <code><strong>budgeted </strong></code> </a></td> <td>
one of: <a href="#SkBudgeted_kNo">SkBudgeted::kNo</a>, <a href="#SkBudgeted_kYes">SkBudgeted::kYes</a></td>
</tr> <tr> <td><a name="SkSurface_MakeRenderTarget_3_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="undocumented#Raster_Surface">Raster Surface</a>; <a href="#SkSurface_width">width</a>, or <a href="#SkSurface_height">height</a>, or both, may be zero</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if all parameters are valid; otherwise, nullptr
### Example
<div><fiddle-embed name="5c7629c15e9ac93f098335e72560fa2e" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeFromBackendRenderTarget">MakeFromBackendRenderTarget</a> <a href="#SkSurface_MakeFromBackendTextureAsRenderTarget">MakeFromBackendTextureAsRenderTarget</a>
---
<a name="SkSurface_MakeNull"></a>
## MakeNull
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
static sk_sp&lt;SkSurface&gt; MakeNull(int width, int height)
</pre>
Returns <a href="#Surface">Surface</a> without backing pixels. Drawing to <a href="SkCanvas_Reference#Canvas">Canvas</a> returned from <a href="#Surface">Surface</a>
has no effect. Calling <a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> on returned <a href="#Surface">Surface</a> returns nullptr.
### Parameters
<table> <tr> <td><a name="SkSurface_MakeNull_width"> <code><strong>width </strong></code> </a></td> <td>
one or greater</td>
</tr> <tr> <td><a name="SkSurface_MakeNull_height"> <code><strong>height </strong></code> </a></td> <td>
one or greater</td>
</tr>
</table>
### Return Value
<a href="#Surface">Surface</a> if <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> are positive; otherwise, nullptr
### Example
<div><fiddle-embed name="99a54b814ccab7d2b1143c88581649ff">
#### Example Output
~~~~
SkSurface::MakeNull(0, 0) == nullptr
surf->makeImageSnapshot() == nullptr
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_MakeRaster">MakeRaster</a> <a href="#SkSurface_MakeRenderTarget">MakeRenderTarget</a>
---
<a name="SkSurface_width"></a>
## width
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
int width() const
</pre>
Returns pixel count in each row; may be zero or greater.
### Return Value
number of pixel columns
### Example
<div><fiddle-embed name="df066b56dd97c7c589fd2bb6a2539de8">
#### Example Output
~~~~
surface width=37 canvas width=37
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_height">height</a>
---
<a name="SkSurface_height"></a>
## height
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
int height() const
</pre>
Returns pixel row count; may be zero or greater.
### Return Value
number of pixel rows
### Example
<div><fiddle-embed name="20571cc23e3146deaa09046b64cc0aef">
#### Example Output
~~~~
surface height=1000 canvas height=1000
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_width">width</a>
---
<a name="SkSurface_generationID"></a>
## generationID
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
uint32_t generationID()
</pre>
Returns unique value identifying the content of <a href="#Surface">Surface</a>. Returned value changes
each time the content changes. Content is changed by drawing, or by calling
<a href="#SkSurface_notifyContentWillChange">notifyContentWillChange</a>.
### Return Value
unique content identifier
### Example
<div><fiddle-embed name="be9574c4a14f891e1abb4ec2b1e51d6c">
#### Example Output
~~~~
surface generationID: 1
surface generationID: 2
surface generationID: 3
~~~~
</fiddle-embed></div>
### See Also
<a href="#SkSurface_notifyContentWillChange">notifyContentWillChange</a> <a href="#SkSurface_ContentChangeMode">ContentChangeMode</a> <a href="#SkSurface_getCanvas">getCanvas</a>
---
## <a name="SkSurface_ContentChangeMode"></a> Enum SkSurface::ContentChangeMode
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
enum <a href="#SkSurface_ContentChangeMode">ContentChangeMode</a> {
<a href="#SkSurface_kDiscard_ContentChangeMode">kDiscard ContentChangeMode</a>,
<a href="#SkSurface_kRetain_ContentChangeMode">kRetain ContentChangeMode</a>,
};</pre>
<a href="#SkSurface_ContentChangeMode">ContentChangeMode</a> members are parameters to <a href="#SkSurface_notifyContentWillChange">notifyContentWillChange</a>.
### Constants
<table>
<tr>
<td><a name="SkSurface_kDiscard_ContentChangeMode"> <code><strong>SkSurface::kDiscard_ContentChangeMode </strong></code> </a></td><td>Pass to notifyContentWillChange to discard surface contents when</td><td>the surface is cleared or overwritten.</td>
</tr>
<tr>
<td><a name="SkSurface_kRetain_ContentChangeMode"> <code><strong>SkSurface::kRetain_ContentChangeMode </strong></code> </a></td><td>Pass to notifyContentWillChange when to preserve surface contents.</td><td>If a snapshot has been generated, this copies the <a href="#Surface">Surface</a> contents.</td>
</tr>
</table>
### See Also
<a href="#SkSurface_notifyContentWillChange">notifyContentWillChange</a> <a href="#SkSurface_generationID">generationID</a>
<a name="SkSurface_notifyContentWillChange"></a>
## notifyContentWillChange
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void notifyContentWillChange(ContentChangeMode mode)
</pre>
Notifies that <a href="#Surface">Surface</a> contents will be changed by code outside of Skia.
Subsequent calls to <a href="#SkSurface_generationID">generationID</a> return a different value.
<a href="#SkSurface_notifyContentWillChange_mode">mode</a> is normally passed as <a href="#SkSurface_kRetain_ContentChangeMode">kRetain ContentChangeMode</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_notifyContentWillChange_mode"> <code><strong>mode </strong></code> </a></td> <td>
one of: <a href="#SkSurface_kDiscard_ContentChangeMode">kDiscard ContentChangeMode</a>, <a href="#SkSurface_kRetain_ContentChangeMode">kRetain ContentChangeMode</a></td>
</tr>
</table>
### Example
<div><fiddle-embed name="be9574c4a14f891e1abb4ec2b1e51d6c"></fiddle-embed></div>
### See Also
<a href="#SkSurface_ContentChangeMode">ContentChangeMode</a> <a href="#SkSurface_generationID">generationID</a>
---
## <a name="SkSurface_BackendHandleAccess"></a> Enum SkSurface::BackendHandleAccess
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
enum <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a> {
<a href="#SkSurface_kFlushRead_BackendHandleAccess">kFlushRead BackendHandleAccess</a>,
<a href="#SkSurface_kFlushWrite_BackendHandleAccess">kFlushWrite BackendHandleAccess</a>,
<a href="#SkSurface_kDiscardWrite_BackendHandleAccess">kDiscardWrite BackendHandleAccess</a>,
};
static const <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a> <a href="#SkSurface_kFlushRead_TextureHandleAccess">kFlushRead TextureHandleAccess</a> =
<a href="#SkSurface_kFlushRead_BackendHandleAccess">kFlushRead BackendHandleAccess</a>;
static const <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a> <a href="#SkSurface_kFlushWrite_TextureHandleAccess">kFlushWrite TextureHandleAccess</a> =
<a href="#SkSurface_kFlushWrite_BackendHandleAccess">kFlushWrite BackendHandleAccess</a>;
static const <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a> <a href="#SkSurface_kDiscardWrite_TextureHandleAccess">kDiscardWrite TextureHandleAccess</a> =
<a href="#SkSurface_kDiscardWrite_BackendHandleAccess">kDiscardWrite BackendHandleAccess</a>;</pre>
### Constants
<table>
<tr>
<td><a name="SkSurface_kFlushRead_BackendHandleAccess"> <code><strong>SkSurface::kFlushRead_BackendHandleAccess </strong></code> </a></td><td>0</td><td>Caller may read from the back-end object.</td>
</tr>
<tr>
<td><a name="SkSurface_kFlushWrite_BackendHandleAccess"> <code><strong>SkSurface::kFlushWrite_BackendHandleAccess </strong></code> </a></td><td>1</td><td>Caller may write to the back-end object.</td>
</tr>
<tr>
<td><a name="SkSurface_kDiscardWrite_BackendHandleAccess"> <code><strong>SkSurface::kDiscardWrite_BackendHandleAccess </strong></code> </a></td><td>2</td><td>Caller must overwrite the entire back-end object.</td>
</tr>
<tr>
<td><a name="SkSurface_kFlushRead_TextureHandleAccess"> <code><strong>SkSurface::kFlushRead_TextureHandleAccess </strong></code> </a></td><td>0</td><td>Deprecated.
</td>
</tr>
<tr>
<td><a name="SkSurface_kFlushWrite_TextureHandleAccess"> <code><strong>SkSurface::kFlushWrite_TextureHandleAccess </strong></code> </a></td><td>1</td><td>Deprecated.
</td>
</tr>
<tr>
<td><a name="SkSurface_kDiscardWrite_TextureHandleAccess"> <code><strong>SkSurface::kDiscardWrite_TextureHandleAccess </strong></code> </a></td><td>2</td><td>Deprecated.
</td>
</tr>
</table>
### Example
<div><fiddle-embed name="260a5ba014b00eeb5a74b3c6b8d31be4" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_getTextureHandle">getTextureHandle</a> <a href="#SkSurface_getRenderTargetHandle">getRenderTargetHandle</a>
<a name="SkSurface_getTextureHandle"></a>
## getTextureHandle
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
GrBackendObject getTextureHandle(BackendHandleAccess backendHandleAccess)
</pre>
Returns the GPU back-end reference of the texture used by <a href="#Surface">Surface</a>, or zero
if <a href="#Surface">Surface</a> is not backed by a GPU texture.
The returned texture handle is only valid until the next <a href="#SkSurface_draw">draw</a> into <a href="#Surface">Surface</a>,
or when <a href="#Surface">Surface</a> is deleted.
### Parameters
<table> <tr> <td><a name="SkSurface_getTextureHandle_backendHandleAccess"> <code><strong>backendHandleAccess </strong></code> </a></td> <td>
one of: <a href="#SkSurface_kFlushRead_BackendHandleAccess">kFlushRead BackendHandleAccess</a>,
<a href="#SkSurface_kFlushWrite_BackendHandleAccess">kFlushWrite BackendHandleAccess</a>, <a href="#SkSurface_kDiscardWrite_BackendHandleAccess">kDiscardWrite BackendHandleAccess</a></td>
</tr>
</table>
### Return Value
GPU texture reference
### Example
<div><fiddle-embed name="4b5720038daaf65ba1ba546e678ddd6e" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_getRenderTargetHandle">getRenderTargetHandle</a> <a href="undocumented#GrBackendObject">GrBackendObject</a> <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a>
---
<a name="SkSurface_getRenderTargetHandle"></a>
## getRenderTargetHandle
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool getRenderTargetHandle(GrBackendObject* backendObject, BackendHandleAccess backendHandleAccess)
</pre>
Returns true and stores the GPU back-end reference of the render target used
by <a href="#Surface">Surface</a> in <a href="#SkSurface_getRenderTargetHandle_backendObject">backendObject</a>.
Return false if <a href="#Surface">Surface</a> is not backed by a GPU render target, and leaves
<a href="#SkSurface_getRenderTargetHandle_backendObject">backendObject</a> unchanged.
The returned render target handle is only valid until the next <a href="#SkSurface_draw">draw</a> into <a href="#Surface">Surface</a>,
or when <a href="#Surface">Surface</a> is deleted.
In OpenGL this returns the frame buffer object ID.
### Parameters
<table> <tr> <td><a name="SkSurface_getRenderTargetHandle_backendObject"> <code><strong>backendObject </strong></code> </a></td> <td>
GPU intermediate memory buffer</td>
</tr> <tr> <td><a name="SkSurface_getRenderTargetHandle_backendHandleAccess"> <code><strong>backendHandleAccess </strong></code> </a></td> <td>
one of: <a href="#SkSurface_kFlushRead_BackendHandleAccess">kFlushRead BackendHandleAccess</a>,
<a href="#SkSurface_kFlushWrite_BackendHandleAccess">kFlushWrite BackendHandleAccess</a>, <a href="#SkSurface_kDiscardWrite_BackendHandleAccess">kDiscardWrite BackendHandleAccess</a></td>
</tr>
</table>
### Return Value
true if <a href="#Surface">Surface</a> is backed by GPU texture
### Example
<div><fiddle-embed name="16e848a4405ce08f8393bba13cc3b8bf" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_getTextureHandle">getTextureHandle</a> <a href="undocumented#GrBackendObject">GrBackendObject</a> <a href="#SkSurface_BackendHandleAccess">BackendHandleAccess</a>
---
<a name="SkSurface_getCanvas"></a>
## getCanvas
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
SkCanvas* getCanvas()
</pre>
Returns <a href="SkCanvas_Reference#Canvas">Canvas</a> that draws into <a href="#Surface">Surface</a>. Subsequent calls return the same <a href="SkCanvas_Reference#Canvas">Canvas</a>.
<a href="SkCanvas_Reference#Canvas">Canvas</a> returned is managed and owned by <a href="#Surface">Surface</a>, and is deleted when <a href="#Surface">Surface</a>
is deleted.
### Return Value
drawing <a href="SkCanvas_Reference#Canvas">Canvas</a> for <a href="#Surface">Surface</a>
### Example
<div><fiddle-embed name="33d0c5ad5a4810e533ae1010e29f8b75"></fiddle-embed></div>
### See Also
<a href="#SkSurface_makeSurface">makeSurface</a> <a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> <a href="#SkSurface_draw">draw</a>
---
<a name="SkSurface_makeSurface"></a>
## makeSurface
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
sk_sp&lt;SkSurface&gt; makeSurface(const SkImageInfo& imageInfo)
</pre>
Returns a compatible <a href="#Surface">Surface</a>, or nullptr. Returned <a href="#Surface">Surface</a> contains
the same raster, GPU, or null properties as the original. Returned <a href="#Surface">Surface</a>
does not share the same pixels.
Returns nullptr if <a href="#SkSurface_makeSurface_imageInfo">imageInfo</a> <a href="#SkSurface_width">width</a> or <a href="#SkSurface_height">height</a> are zero, or if <a href="#SkSurface_makeSurface_imageInfo">imageInfo</a>
is incompatible with <a href="#Surface">Surface</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_makeSurface_imageInfo"> <code><strong>imageInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>, <a href="undocumented#Color_Space">Color Space</a>,
of <a href="#Surface">Surface</a>; <a href="#SkSurface_width">width</a> and <a href="#SkSurface_height">height</a> must be greater than zero</td>
</tr>
</table>
### Return Value
compatible <a href="#Surface">Surface</a> or nullptr
### Example
<div><fiddle-embed name="a9889b519a26896b900da0444e423c61"></fiddle-embed></div>
### See Also
<a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> <a href="#SkSurface_getCanvas">getCanvas</a> <a href="#SkSurface_draw">draw</a>
---
<a name="SkSurface_makeImageSnapshot"></a>
## makeImageSnapshot
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
sk_sp&lt;SkImage&gt; makeImageSnapshot()
</pre>
Returns <a href="SkImage_Reference#Image">Image</a> capturing <a href="#Surface">Surface</a> contents. Subsequent drawing to <a href="#Surface">Surface</a> contents
are not captured. <a href="SkImage_Reference#Image">Image</a> allocation is accounted for if <a href="#Surface">Surface</a> was created with
<a href="#SkBudgeted_kYes">SkBudgeted::kYes</a>.
### Return Value
<a href="SkImage_Reference#Image">Image</a> initialized with <a href="#Surface">Surface</a> contents
### Example
<div><fiddle-embed name="46f1fa0d95e590a64bed0140407ce5f7"></fiddle-embed></div>
### See Also
<a href="#SkSurface_draw">draw</a> <a href="#SkSurface_getCanvas">getCanvas</a>
---
<a name="SkSurface_draw"></a>
## draw
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void draw(SkCanvas* canvas, SkScalar x, SkScalar y, const SkPaint* paint)
</pre>
Draws <a href="#Surface">Surface</a> contents to <a href="#SkSurface_draw_canvas">canvas</a>, with its top-left corner at (<a href="#SkSurface_draw_x">x</a>, <a href="#SkSurface_draw_y">y</a>).
If <a href="SkPaint_Reference#Paint">Paint</a> <a href="#SkSurface_draw_paint">paint</a> is not nullptr, apply <a href="undocumented#Color_Filter">Color Filter</a>, <a href="#Alpha">Color Alpha</a>, <a href="undocumented#Image_Filter">Image Filter</a>,
<a href="undocumented#Blend_Mode">Blend Mode</a>, and <a href="undocumented#Draw_Looper">Draw Looper</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_draw_canvas"> <code><strong>canvas </strong></code> </a></td> <td>
<a href="SkCanvas_Reference#Canvas">Canvas</a> drawn into</td>
</tr> <tr> <td><a name="SkSurface_draw_x"> <code><strong>x </strong></code> </a></td> <td>
horizontal offset in <a href="SkCanvas_Reference#Canvas">Canvas</a></td>
</tr> <tr> <td><a name="SkSurface_draw_y"> <code><strong>y </strong></code> </a></td> <td>
vertical offset in <a href="SkCanvas_Reference#Canvas">Canvas</a></td>
</tr> <tr> <td><a name="SkSurface_draw_paint"> <code><strong>paint </strong></code> </a></td> <td>
<a href="SkPaint_Reference#Paint">Paint</a> containing <a href="undocumented#Blend_Mode">Blend Mode</a>, <a href="undocumented#Color_Filter">Color Filter</a>, <a href="undocumented#Image_Filter">Image Filter</a>,
and so on; or nullptr</td>
</tr>
</table>
### Example
<div><fiddle-embed name="0de693f4d8dd898a60be8cfba23952be"></fiddle-embed></div>
### See Also
<a href="#SkSurface_makeImageSnapshot">makeImageSnapshot</a> <a href="#SkSurface_getCanvas">getCanvas</a>
---
<a name="SkSurface_peekPixels"></a>
## peekPixels
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool peekPixels(SkPixmap* pixmap)
</pre>
Copies <a href="#Surface">Surface</a> pixel address, row bytes, and <a href="undocumented#Image_Info">Image Info</a> to <a href="SkPixmap_Reference#Pixmap">Pixmap</a>, if address
is available, and returns true. If pixel address is not available, return
false and leave <a href="SkPixmap_Reference#Pixmap">Pixmap</a> unchanged.
<a href="#SkSurface_peekPixels_pixmap">pixmap</a> contents become invalid on any future change to <a href="#Surface">Surface</a>.
### Parameters
<table> <tr> <td><a name="SkSurface_peekPixels_pixmap"> <code><strong>pixmap </strong></code> </a></td> <td>
storage for pixel state if pixels are readable; otherwise, ignored</td>
</tr>
</table>
### Return Value
true if <a href="#Surface">Surface</a> has direct access to pixels
### Example
<div><fiddle-embed name="8c6184f22cfe068f021704cf92a147a1"></fiddle-embed></div>
### See Also
<a href="#SkSurface_readPixels">readPixels</a>
---
<a name="SkSurface_readPixels"></a>
## readPixels
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool readPixels(const SkPixmap& dst, int srcX, int srcY)
</pre>
Copies <a href="SkRect_Reference#Rect">Rect</a> of pixels to <a href="#SkSurface_readPixels_dst">dst</a>.
Source <a href="SkRect_Reference#Rect">Rect</a> corners are (<a href="#SkSurface_readPixels_srcX">srcX</a>, <a href="#SkSurface_readPixels_srcY">srcY</a>) and <a href="#Surface">Surface</a> (<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>).
Destination <a href="SkRect_Reference#Rect">Rect</a> corners are (0, 0) and (<a href="#SkSurface_readPixels_dst">dst</a>.<a href="#SkSurface_width">width</a>, <a href="#SkSurface_readPixels_dst">dst</a>.<a href="#SkSurface_height">height</a>).
Copies each readable pixel intersecting both rectangles, without scaling,
converting to <a href="#SkSurface_readPixels_dst">dst</a>.colorType() and <a href="#SkSurface_readPixels_dst">dst</a>.alphaType() if required.
Pixels are readable when <a href="#Surface">Surface</a> is raster, or backed by a GPU.
The destination pixel storage must be allocated by the caller.
<a href="undocumented#Pixel">Pixel</a> values are converted only if <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>
do not match. Only pixels within both source and destination rectangles
are copied. <a href="#SkSurface_readPixels_dst">dst</a> contents outside <a href="SkRect_Reference#Rect">Rect</a> intersection are unchanged.
Pass negative values for <a href="#SkSurface_readPixels_srcX">srcX</a> or <a href="#SkSurface_readPixels_srcY">srcY</a> to offset pixels across or down destination.
Does not copy, and returns false if:
<table> <tr>
<td>Source and destination rectangles do not intersect.</td> </tr> <tr>
<td><a href="SkPixmap_Reference#Pixmap">Pixmap</a> pixels could not be allocated.</td> </tr> <tr>
<td><a href="#SkSurface_readPixels_dst">dst</a>.rowBytes() is too small to contain one row of pixels.</td> </tr>
</table>
### Parameters
<table> <tr> <td><a name="SkSurface_readPixels_dst"> <code><strong>dst </strong></code> </a></td> <td>
storage for pixels copied from <a href="#Surface">Surface</a></td>
</tr> <tr> <td><a name="SkSurface_readPixels_srcX"> <code><strong>srcX </strong></code> </a></td> <td>
offset into readable pixels in x; may be negative</td>
</tr> <tr> <td><a name="SkSurface_readPixels_srcY"> <code><strong>srcY </strong></code> </a></td> <td>
offset into readable pixels in y; may be negative</td>
</tr>
</table>
### Return Value
true if pixels were copied
### Example
<div><fiddle-embed name="9f454fb93bca6482598d198b4121f0a6"></fiddle-embed></div>
### See Also
<a href="#SkSurface_peekPixels">peekPixels</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool readPixels(const SkImageInfo& dstInfo, void* dstPixels, size_t dstRowBytes, int srcX, int srcY)
</pre>
Copies <a href="SkRect_Reference#Rect">Rect</a> of pixels from <a href="SkCanvas_Reference#Canvas">Canvas</a> into <a href="#SkSurface_readPixels_2_dstPixels">dstPixels</a>.
Source <a href="SkRect_Reference#Rect">Rect</a> corners are (<a href="#SkSurface_readPixels_2_srcX">srcX</a>, <a href="#SkSurface_readPixels_2_srcY">srcY</a>) and <a href="#Surface">Surface</a> (<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>).
Destination <a href="SkRect_Reference#Rect">Rect</a> corners are (0, 0) and (<a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.<a href="#SkSurface_width">width</a>, <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.<a href="#SkSurface_height">height</a>).
Copies each readable pixel intersecting both rectangles, without scaling,
converting to <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.colorType() and <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.alphaType() if required.
Pixels are readable when <a href="#Surface">Surface</a> is raster, or backed by a GPU.
The destination pixel storage must be allocated by the caller.
<a href="undocumented#Pixel">Pixel</a> values are converted only if <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>
do not match. Only pixels within both source and destination rectangles
are copied. <a href="#SkSurface_readPixels_2_dstPixels">dstPixels</a> contents outside <a href="SkRect_Reference#Rect">Rect</a> intersection are unchanged.
Pass negative values for <a href="#SkSurface_readPixels_2_srcX">srcX</a> or <a href="#SkSurface_readPixels_2_srcY">srcY</a> to offset pixels across or down destination.
Does not copy, and returns false if:
<table> <tr>
<td>Source and destination rectangles do not intersect.</td> </tr> <tr>
<td><a href="#Surface">Surface</a> pixels could not be converted to <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.colorType() or <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.alphaType().</td> </tr> <tr>
<td><a href="#SkSurface_readPixels_2_dstRowBytes">dstRowBytes</a> is too small to contain one row of pixels.</td> </tr>
</table>
### Parameters
<table> <tr> <td><a name="SkSurface_readPixels_2_dstInfo"> <code><strong>dstInfo </strong></code> </a></td> <td>
<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>, <a href="undocumented#Image_Color_Type">Image Color Type</a>, and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a> of <a href="#SkSurface_readPixels_2_dstPixels">dstPixels</a></td>
</tr> <tr> <td><a name="SkSurface_readPixels_2_dstPixels"> <code><strong>dstPixels </strong></code> </a></td> <td>
storage for pixels; <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.<a href="#SkSurface_height">height</a> times <a href="#SkSurface_readPixels_2_dstRowBytes">dstRowBytes</a>, or larger</td>
</tr> <tr> <td><a name="SkSurface_readPixels_2_dstRowBytes"> <code><strong>dstRowBytes </strong></code> </a></td> <td>
size of one destination row; <a href="#SkSurface_readPixels_2_dstInfo">dstInfo</a>.<a href="#SkSurface_width">width</a> times pixel size, or larger</td>
</tr> <tr> <td><a name="SkSurface_readPixels_2_srcX"> <code><strong>srcX </strong></code> </a></td> <td>
offset into readable pixels in x; may be negative</td>
</tr> <tr> <td><a name="SkSurface_readPixels_2_srcY"> <code><strong>srcY </strong></code> </a></td> <td>
offset into readable pixels in y; may be negative</td>
</tr>
</table>
### Return Value
true if pixels were copied
### Example
<div><fiddle-embed name="d141d6c662d201d191fb1eea26d014fd"><div>A black oval drawn on a red background provides an image to copy.
<a href="#SkSurface_readPixels">readPixels</a> copies one quarter of the <a href="#Surface">Surface</a> into each of the four corners.
The copied quarter ovals overdraw the original oval.</div></fiddle-embed></div>
### See Also
<a href="#SkSurface_peekPixels">peekPixels</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool readPixels(const SkBitmap& dst, int srcX, int srcY)
</pre>
Copies <a href="SkRect_Reference#Rect">Rect</a> of pixels from <a href="#Surface">Surface</a> into bitmap.
Source <a href="SkRect_Reference#Rect">Rect</a> corners are (<a href="#SkSurface_readPixels_3_srcX">srcX</a>, <a href="#SkSurface_readPixels_3_srcY">srcY</a>) and <a href="#Surface">Surface</a> (<a href="#SkSurface_width">width</a>, <a href="#SkSurface_height">height</a>).
Destination <a href="SkRect_Reference#Rect">Rect</a> corners are (0, 0) and (bitmap.<a href="#SkSurface_width">width</a>, bitmap.<a href="#SkSurface_height">height</a>).
Copies each readable pixel intersecting both rectangles, without scaling,
converting to bitmap.colorType() and bitmap.alphaType() if required.
Pixels are readable when <a href="#Surface">Surface</a> is raster, or backed by a GPU.
The destination pixel storage must be allocated by the caller.
<a href="undocumented#Pixel">Pixel</a> values are converted only if <a href="undocumented#Image_Color_Type">Image Color Type</a> and <a href="undocumented#Image_Alpha_Type">Image Alpha Type</a>
do not match. Only pixels within both source and destination rectangles
are copied. <a href="#SkSurface_readPixels_3_dst">dst</a> contents outside <a href="SkRect_Reference#Rect">Rect</a> intersection are unchanged.
Pass negative values for <a href="#SkSurface_readPixels_3_srcX">srcX</a> or <a href="#SkSurface_readPixels_3_srcY">srcY</a> to offset pixels across or down destination.
Does not copy, and returns false if:
<table> <tr>
<td>Source and destination rectangles do not intersect.</td> </tr> <tr>
<td><a href="#Surface">Surface</a> pixels could not be converted to <a href="#SkSurface_readPixels_3_dst">dst</a>.colorType() or <a href="#SkSurface_readPixels_3_dst">dst</a>.alphaType().</td> </tr> <tr>
<td><a href="#SkSurface_readPixels_3_dst">dst</a> pixels could not be allocated.</td> </tr> <tr>
<td><a href="#SkSurface_readPixels_3_dst">dst</a>.rowBytes() is too small to contain one row of pixels.</td> </tr>
</table>
### Parameters
<table> <tr> <td><a name="SkSurface_readPixels_3_dst"> <code><strong>dst </strong></code> </a></td> <td>
storage for pixels copied from <a href="#Surface">Surface</a></td>
</tr> <tr> <td><a name="SkSurface_readPixels_3_srcX"> <code><strong>srcX </strong></code> </a></td> <td>
offset into readable pixels in x; may be negative</td>
</tr> <tr> <td><a name="SkSurface_readPixels_3_srcY"> <code><strong>srcY </strong></code> </a></td> <td>
offset into readable pixels in y; may be negative</td>
</tr>
</table>
### Return Value
true if pixels were copied
### Example
<div><fiddle-embed name="dcbd4af9151820f63de45a35f3a8d110"></fiddle-embed></div>
### See Also
<a href="#SkSurface_peekPixels">peekPixels</a>
---
<a name="SkSurface_props"></a>
## props
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
const SkSurfaceProps& props() const
</pre>
Returns <a href="#Properties">Surface Properties</a> for surface.
### Return Value
LCD striping orientation and setting for device independent fonts
### Example
<div><fiddle-embed name="13cf9e7b2894ae6e98c1fd719040bf01">
#### Example Output
~~~~
surf.props(): kRGB_H_SkPixelGeometry
~~~~
</fiddle-embed></div>
### See Also
<a href="undocumented#SkSurfaceProps">SkSurfaceProps</a>
---
<a name="SkSurface_prepareForExternalIO"></a>
## prepareForExternalIO
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void prepareForExternalIO()
</pre>
To be deprecated.
---
<a name="SkSurface_flush"></a>
## flush
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
void flush()
</pre>
Issues pending <a href="#Surface">Surface</a> commands to the GPU-backed API and resolves any <a href="#Surface">Surface</a> MSAA.
Skia flushes as needed, so it is not necessary to call this if Skia manages
drawing and object lifetime. Call when interleaving Skia calls with native
GPU calls.
### See Also
<a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a>
---
<a name="SkSurface_flushAndSignalSemaphores"></a>
## flushAndSignalSemaphores
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
GrSemaphoresSubmitted flushAndSignalSemaphores(int numSemaphores,
GrBackendSemaphore signalSemaphores[])
</pre>
Issues pending <a href="#Surface">Surface</a> commands to the GPU-backed API and resolves any <a href="#Surface">Surface</a> MSAA.
After issuing all commands, <a href="#SkSurface_flushAndSignalSemaphores_signalSemaphores">signalSemaphores</a> of count <a href="#SkSurface_flushAndSignalSemaphores_numSemaphores">numSemaphores</a> semaphores
are signaled by the GPU.
For each <a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a> in <a href="#SkSurface_flushAndSignalSemaphores_signalSemaphores">signalSemaphores</a>:
if <a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a> is initialized, the GPU back-end uses the semaphore as is;
otherwise, a new semaphore is created and initializes <a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a>.
The caller must delete the semaphores created and returned in <a href="#SkSurface_flushAndSignalSemaphores_signalSemaphores">signalSemaphores</a>.
<a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a> can be deleted as soon as this function returns.
If the back-end API is OpenGL only uninitialized <a href="#GrBackendSemaphore">GrBackendSemaphores</a> are supported.
If the back-end API is Vulkan semaphores may be initialized or uninitialized.
If uninitialized, created semaphores are valid only with the VkDevice
with which they were created.
If <a href="#kNo">GrSemaphoresSubmitted::kNo</a> is returned, the GPU back-end did not create or
add any semaphores to signal on the GPU; the caller should not instruct the GPU
to <a href="#SkSurface_wait">wait</a> on any of the semaphores.
Pending surface commands are flushed regardless of the return result.
### Parameters
<table> <tr> <td><a name="SkSurface_flushAndSignalSemaphores_numSemaphores"> <code><strong>numSemaphores </strong></code> </a></td> <td>
size of <a href="#SkSurface_flushAndSignalSemaphores_signalSemaphores">signalSemaphores</a> array</td>
</tr> <tr> <td><a name="SkSurface_flushAndSignalSemaphores_signalSemaphores"> <code><strong>signalSemaphores </strong></code> </a></td> <td>
array of semaphore containers</td>
</tr>
</table>
### Return Value
one of: <a href="#kYes">GrSemaphoresSubmitted::kYes</a>, <a href="#kNo">GrSemaphoresSubmitted::kNo</a>
### See Also
<a href="#SkSurface_wait">wait</a> <a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a>
---
<a name="SkSurface_wait"></a>
## wait
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool wait(int numSemaphores, const GrBackendSemaphore* waitSemaphores)
</pre>
Inserts a list of GPU semaphores that the current GPU-backed API must <a href="#SkSurface_wait">wait</a> on before
executing any more commands on the GPU for this surface. Skia will take ownership of the
underlying semaphores and delete them once they have been signaled and waited on.
If this call returns false, then the GPU back-end will not <a href="#SkSurface_wait">wait</a> on any passed in semaphores,
and the client will still own the semaphores.
### Parameters
<table> <tr> <td><a name="SkSurface_wait_numSemaphores"> <code><strong>numSemaphores </strong></code> </a></td> <td>
size of <a href="#SkSurface_wait_waitSemaphores">waitSemaphores</a> array</td>
</tr> <tr> <td><a name="SkSurface_wait_waitSemaphores"> <code><strong>waitSemaphores </strong></code> </a></td> <td>
array of semaphore containers</td>
</tr>
</table>
### Return Value
true if GPU is waiting on semaphores
### Example
<div><fiddle-embed name="c9033080af68efc0f270d748f1c0e011"></fiddle-embed></div>
### See Also
<a href="#SkSurface_flushAndSignalSemaphores">flushAndSignalSemaphores</a> <a href="undocumented#GrBackendSemaphore">GrBackendSemaphore</a>
---
<a name="SkSurface_characterize"></a>
## characterize
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool characterize(SkSurfaceCharacterization* characterization) const
</pre>
Initializes <a href="#Characterization">Surface Characterization</a> that can be used to perform GPU back-end
pre-processing in a separate thread. Typically this is used to divide drawing
into multiple tiles. DeferredDisplayListRecorder records the drawing commands
for each tile.
Return true if <a href="#Surface">Surface</a> supports <a href="#SkSurface_characterize_characterization">characterization</a>. <a href="undocumented#Raster_Surface">Raster Surface</a> returns false.
### Parameters
<table> <tr> <td><a name="SkSurface_characterize_characterization"> <code><strong>characterization </strong></code> </a></td> <td>
properties for parallel drawing</td>
</tr>
</table>
### Return Value
true if supported
### Example
<div><fiddle-embed name="3df4e2fc63483a3fa19589b5388080bc" gpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_draw">draw</a> <a href="undocumented#SkSurfaceCharacterization">SkSurfaceCharacterization</a> <a href="undocumented#SkDeferredDisplayList">SkDeferredDisplayList</a>
---
<pre style="padding: 1em 1em 1em 1em;width: 62.5em; background-color: #f0f0f0">
bool draw(SkDeferredDisplayList* deferredDisplayList)
</pre>
Draws deferred display list created using <a href="undocumented#SkDeferredDisplayListRecorder">SkDeferredDisplayListRecorder</a>.
Has no effect and returns false if <a href="#Characterization">Surface Characterization</a> stored in
<a href="#SkSurface_draw_2_deferredDisplayList">deferredDisplayList</a> is not compatible with <a href="#Surface">Surface</a>.
<a href="undocumented#Raster_Surface">Raster Surface</a> returns false.
### Parameters
<table> <tr> <td><a name="SkSurface_draw_2_deferredDisplayList"> <code><strong>deferredDisplayList </strong></code> </a></td> <td>
drawing commands</td>
</tr>
</table>
### Return Value
false if <a href="#SkSurface_draw_2_deferredDisplayList">deferredDisplayList</a> is not compatible
### Example
<div><fiddle-embed name="3dfa7496268dfb2c7465cda5da39dfbd" gpu="true" cpu="true"></fiddle-embed></div>
### See Also
<a href="#SkSurface_characterize">characterize</a> <a href="undocumented#SkSurfaceCharacterization">SkSurfaceCharacterization</a> <a href="undocumented#SkDeferredDisplayList">SkDeferredDisplayList</a>
---