Class Handle

java.lang.Object
org.javagi.base.ProxyInstance
org.gnome.gobject.TypeInstance
org.gnome.gobject.GObject
org.gnome.rsvg.Handle
All Implemented Interfaces:
Proxy
@Generated("org.javagi.JavaGI") public class Handle extends GObject

Handle loads an SVG document into memory.

This is the main entry point into the librsvg library. An Handle is an object that represents SVG data in memory. Your program creates an Handle from an SVG file, or from a memory buffer that contains SVG data, or in the most general form, from a GInputStream that will provide SVG data.

Librsvg can load SVG images and render them to Cairo surfaces, using a mixture of SVG's Rsvg.Handle.new_from_data without calling setBaseUri(String), then any referenced files will not be allowed (e.g. raster images to be loaded from other files will not work).

  1. If referenced URLs are absolute, rather than relative, then they must have the same scheme as the base URL. For example, if the base URL has a file scheme, then all URL references inside the SVG must also have the file scheme, or be relative references which will be resolved against the base URL.

  2. If referenced URLs have a resource scheme, that is, if they are included into your binary program with GLib's resource mechanism, they are allowed to be loaded (provided that the base URL is also a resource, per the previous rule).

  3. Otherwise, non-file schemes are not allowed. For example, librsvg will not load http resources, to keep malicious SVG data from "phoning home".

  4. URLs with a file scheme are rejected if they contain a hostname, as in file://hostname/some/directory/foo.svg. Windows UNC paths with a hostname are also rejected. This is to prevent documents from trying to access resources on other machines.

  5. A relative URL must resolve to the same directory as the base URL, or to one of its subdirectories. Librsvg will canonicalize filenames, by removing ".." path components and resolving symbolic links, to decide whether files meet these conditions.

Loading an SVG with GIO

This is the easiest and most resource-efficient way of loading SVG data into an Handle.

If you have a GFile that stands for an SVG file, you can simply call fromGfileSync(File, Set, Cancellable) to load an Handle from it.

Alternatively, if you have a GInputStream, you can use fromStreamSync(InputStream, File, Set, Cancellable).

Both of those methods allow specifying a GCancellable, so the loading process can be cancelled from another thread.

Loading an SVG from memory

If you already have SVG data in a byte buffer in memory, you can create a memory input stream with MemoryInputStream#fromData and feed that to fromStreamSync(InputStream, File, Set, Cancellable).

Note that in this case, it is important that you specify the base_file for the in-memory SVG data. Librsvg uses the base_file to resolve links to external content, like raster images.

Loading an SVG without GIO

You can load an Handle from a simple filename or URI with fromFile(String). Note that this is a blocking operation; there is no way to cancel it if loading a remote URI takes a long time. Also, note that this method does not let you specify Rsvg.HandleFlags.

Otherwise, loading an SVG without GIO is not recommended, since librsvg will need to buffer your entire data internally before actually being able to parse it. The deprecated way of doing this is by creating a handle with Handle() or withFlags(Set), and then using write(byte[]) and close() to feed the handle with SVG data. Still, please try to use the GIO stream functions instead.

Resolution of the rendered image (dots per inch, or DPI)

SVG images can contain dimensions like "5cm" or "2pt" that must be converted from physical units into device units. To do this, librsvg needs to know the actual dots per inch (DPI) of your target device. You can call setDpi(double) or setDpiXY(double, double) on an Handle to set the DPI before rendering it.

For historical reasons, the default DPI is 90. Current CSS assumes a default DPI of 96, so you may want to set the DPI of a Handle immediately after creating it with setDpi(double).

Rendering

The preferred way to render a whole SVG document is to use renderDocument(Context, Rectangle). Please see its documentation for details.

API ordering

Due to the way the librsvg API evolved over time, an Handle object is available for use as soon as it is constructed. However, not all of its methods can be called at any time. For example, an Handle just constructed with Handle() is not loaded yet, and it does not make sense to call renderDocument(Context, Rectangle) on it just at that point.

The documentation for the available methods in Handle may mention that a particular method is only callable on a "fully loaded handle". This means either:

Before librsvg 2.46, the library did not fully verify that a handle was in a fully loaded state for the methods that require it. To preserve compatibility with old code which inadvertently called the API without checking for errors, or which called some methods outside of the expected order, librsvg will just emit a g_critical() message in those cases.

New methods introduced in librsvg 2.46 and later will check for the correct ordering, and panic if they are called out of order. This will abort the program as if it had a failed assertion.

  • Constructor Details

    • Handle

      public Handle(MemorySegment address)
      Create a Handle instance for the provided memory address.
      Parameters:
      address - the memory address of the native object

    • Handle

      public Handle()
      Create a new Handle.

  • Method Details

    • getType

      public static @Nullable Type getType()
      Get the GType of the Handle class.
      Returns:
      the GType

    • getMemoryLayout

      public static MemoryLayout getMemoryLayout()
      The memory layout of the native struct.
      Returns:
      the memory layout

    • asParent

      protected Handle asParent()
      Return this instance as if it were its parent type. Comparable to the Java super keyword, but ensures the parent typeclass is also used in native code.
      Overrides:
      asParent in class GObject
      Returns:
      the instance as if it were its parent type

    • fromData

      public static Handle fromData(@Nullable byte @Nullable [] data) throws GErrorException
      Loads the SVG specified by data. Note that this function creates an Handle without a base URL, and without any Rsvg.HandleFlags. If you need these, use fromStreamSync(InputStream, File, Set, Cancellable) instead by creating a MemoryInputStream from your data.
      Parameters:
      data - The SVG data
      Returns:
      A Handle or NULL if an error occurs.
      Throws:
      GErrorException - see GError
      Since:
      2.14

    • fromFile

      public static Handle fromFile(String filename) throws GErrorException
      Loads the SVG specified by fileName. Note that this function, like Handle(), does not specify any loading flags for the resulting handle. If you require the use of Rsvg.HandleFlags, use fromGfileSync(File, Set, Cancellable).
      Parameters:
      filename - The file name to load, or a URI.
      Returns:
      A Handle or NULL if an error occurs.
      Throws:
      GErrorException - see GError
      Since:
      2.14

    • fromGfileSync

      public static Handle fromGfileSync(File file, Set<HandleFlags> flags, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new Handle for file.

      This function sets the "base file" of the handle to be file itself, so SVG elements like <image> which reference external resources will be resolved relative to the location of file.

      If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned in error.

      Parameters:
      file - a GFile
      flags - flags from Rsvg.HandleFlags
      cancellable - a GCancellable, or NULL
      Returns:
      a new Handle on success, or NULL with error filled in
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • fromGfileSync

      public static Handle fromGfileSync(File file, HandleFlags flags, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new Handle for file.

      This function sets the "base file" of the handle to be file itself, so SVG elements like <image> which reference external resources will be resolved relative to the location of file.

      If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned in error.

      Parameters:
      file - a GFile
      flags - flags from Rsvg.HandleFlags
      cancellable - a GCancellable, or NULL
      Returns:
      a new Handle on success, or NULL with error filled in
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • fromStreamSync

      public static Handle fromStreamSync(InputStream inputStream, @Nullable File baseFile, Set<HandleFlags> flags, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new Handle for stream.

      This function sets the "base file" of the handle to be baseFile if provided. SVG elements like <image> which reference external resources will be resolved relative to the location of baseFile.

      If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned in error.

      Parameters:
      inputStream - a GInputStream
      baseFile - a GFile, or NULL
      flags - flags from Rsvg.HandleFlags
      cancellable - a GCancellable, or NULL
      Returns:
      a new Handle on success, or NULL with error filled in
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • fromStreamSync

      public static Handle fromStreamSync(InputStream inputStream, @Nullable File baseFile, HandleFlags flags, @Nullable Cancellable cancellable) throws GErrorException

      Creates a new Handle for stream.

      This function sets the "base file" of the handle to be baseFile if provided. SVG elements like <image> which reference external resources will be resolved relative to the location of baseFile.

      If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned in error.

      Parameters:
      inputStream - a GInputStream
      baseFile - a GFile, or NULL
      flags - flags from Rsvg.HandleFlags
      cancellable - a GCancellable, or NULL
      Returns:
      a new Handle on success, or NULL with error filled in
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • withFlags

      public static Handle withFlags(Set<HandleFlags> flags)
      Creates a new Handle with flags flags. After calling this function, you can feed the resulting handle with SVG data by using readStreamSync(InputStream, Cancellable).
      Parameters:
      flags - flags from Rsvg.HandleFlags
      Returns:
      a new Handle
      Since:
      2.36

    • withFlags

      public static Handle withFlags(HandleFlags... flags)
      Creates a new Handle with flags flags. After calling this function, you can feed the resulting handle with SVG data by using readStreamSync(InputStream, Cancellable).
      Parameters:
      flags - flags from Rsvg.HandleFlags
      Returns:
      a new Handle
      Since:
      2.36

    • close

      @Deprecated public boolean close() throws GErrorException
      Deprecated.
      Use readStreamSync(InputStream, Cancellable) or the constructor functions fromGfileSync(File, Set, Cancellable) or fromStreamSync(InputStream, File, Set, Cancellable). See the deprecation notes for write(byte[]) for more information.

      This is used after calling write(byte[]) to indicate that there is no more data to consume, and to start the actual parsing of the SVG document. The only reason to call this function is if you use use write(byte[]) to feed data into the handle; if you use the other methods like fromFile(String) or readStreamSync(InputStream, Cancellable), then you do not need to call this function.

      This will return TRUE if the loader closed successfully and the SVG data was parsed correctly. Note that this Handle isn't freed until GObject#unref is called.

      Returns:
      TRUE on success, or FALSE on error.
      Throws:
      GErrorException - see GError

    • free

      @Deprecated public void free()
      Deprecated.
      Use GObject#unref instead.
      Frees handle.

    • getBaseUri

      public String getBaseUri()
      Gets the base uri for this Handle.
      Returns:
      the base uri, possibly null
      Since:
      2.8

    • getDesc

      @Deprecated public @Nullable String getDesc()
      Deprecated.

    • getDimensions

      @Deprecated public void getDimensions(DimensionData dimensionData)
      Deprecated.
      Use getIntrinsicSizeInPixels(Out, Out) instead. This function is deprecated because it is not able to return exact fractional dimensions, only integer pixels.

      Get the SVG's size. Do not call from within the size_func callback, because an infinite loop will occur.

      This function depends on the Handle's DPI to compute dimensions in pixels, so you should call setDpi(double) beforehand.

      Parameters:
      dimensionData - A place to store the SVG's size
      Since:
      2.14

    • getDimensionsSub

      @Deprecated public boolean getDimensionsSub(DimensionData dimensionData, @Nullable String id)
      Deprecated.
      Use getGeometryForLayer(String, Rectangle, Rectangle, Rectangle) instead.

      Get the size of a subelement of the SVG file. Do not call from within the size_func callback, because an infinite loop will occur.

      This function depends on the Handle's DPI to compute dimensions in pixels, so you should call setDpi(double) beforehand.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      Parameters:
      dimensionData - A place to store the SVG's size
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to use the whole SVG.
      Returns:
      TRUE if the dimensions could be obtained, FALSE if there was an error.
      Since:
      2.22

    • getGeometryForElement

      public boolean getGeometryForElement(@Nullable String id, @Nullable Rectangle outInkRect, @Nullable Rectangle outLogicalRect) throws GErrorException

      Computes the ink rectangle and logical rectangle of a single SVG element.

      While rsvg_handle_get_geometry_for_layer computes the geometry of an SVG element subtree with its transformation matrix, this other function will compute the element's geometry as if it were being rendered under an identity transformation by itself. That is, the resulting geometry is as if the element got extracted by itself from the SVG.

      This function is the counterpart to rsvg_handle_render_element.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      The "ink rectangle" is the bounding box that would be painted for fully- stroked and filled elements.

      The "logical rectangle" just takes into account the unstroked paths and text outlines.

      Note that these bounds are not minimum bounds; for example, clipping paths are not taken into account.

      You can pass NULL for the id if you want to measure all the elements in the SVG, i.e. to measure everything from the root element.

      This operation is not constant-time, as it involves going through all the child elements.

      Parameters:
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to compute the geometry for the whole SVG.
      outInkRect - Place to store the ink rectangle of the element.
      outLogicalRect - Place to store the logical rectangle of the element.
      Returns:

      TRUE if the geometry could be obtained, or FALSE on error. Errors are returned in the error argument.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Throws:
      GErrorException - see GError
      Since:
      2.46

    • getGeometryForLayer

      public boolean getGeometryForLayer(@Nullable String id, Rectangle viewport, @Nullable Rectangle outInkRect, @Nullable Rectangle outLogicalRect) throws GErrorException

      Computes the ink rectangle and logical rectangle of an SVG element, or the whole SVG, as if the whole SVG were rendered to a specific viewport.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      The "ink rectangle" is the bounding box that would be painted for fully-stroked and filled elements.

      The "logical rectangle" just takes into account the unstroked paths and text outlines.

      Note that these bounds are not minimum bounds; for example, clipping paths are not taken into account.

      You can pass NULL for the id if you want to measure all the elements in the SVG, i.e. to measure everything from the root element.

      This operation is not constant-time, as it involves going through all the child elements.

      Parameters:
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to compute the geometry for the whole SVG.
      viewport - Viewport size at which the whole SVG would be fitted.
      outInkRect - Place to store the ink rectangle of the element.
      outLogicalRect - Place to store the logical rectangle of the element.
      Returns:

      TRUE if the geometry could be obtained, or FALSE on error. Errors are returned in the error argument.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Throws:
      GErrorException - see GError
      Since:
      2.46

    • getIntrinsicDimensions

      public void getIntrinsicDimensions(@Nullable Out<Boolean> outHasWidth, @Nullable Length outWidth, @Nullable Out<Boolean> outHasHeight, @Nullable Length outHeight, @Nullable Out<Boolean> outHasViewbox, @Nullable Rectangle outViewbox)

      In simple terms, queries the width, height, and viewBox attributes in an SVG document.

      If you are calling this function to compute a scaling factor to render the SVG, consider simply using renderDocument(Context, Rectangle) instead; it will do the scaling computations automatically.

      Before librsvg 2.54.0, the out_has_width and out_has_height arguments would be set to true or false depending on whether the SVG document actually had width and height attributes, respectively.

      However, since librsvg 2.54.0, width and height are now geometry properties per the SVG2 specification; they are not plain attributes. SVG2 made it so that the initial value of those properties is auto, which is equivalent to specifing a value of 100%. In this sense, even SVG documents which lack width or height attributes semantically have to make them default to 100%. This is why since librsvg 2.54.0, out_has_width and out_has_heigth are always returned as TRUE, since with SVG2 all documents have a default width and height of 100%.

      As an example, the following SVG element has a width of 100 pixels and a height of 400 pixels, but no viewBox. This function will return those sizes in out_width and out_height, and set out_has_viewbox to FALSE.

      <svg xmlns="http://www.w3.org/2000/svg" width="100" height="400">

      Conversely, the following element has a viewBox, but no width or height. This function will set out_has_viewbox to TRUE, and it will also set out_has_width and out_has_height to TRUE but return both length values as 100%.

      <svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 400">

      Note that the RsvgLength return values have RsvgUnits in them; you should not assume that they are always in pixels. For example, the following SVG element will return width and height values whose units fields are RSVG_UNIT_MM.

      <svg xmlns="http://www.w3.org/2000/svg" width="210mm" height="297mm">

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Parameters:
      outHasWidth - Will be set to TRUE; see below.
      outWidth - Will be set to the computed value of the width property in the toplevel SVG.
      outHasHeight - Will be set to TRUE; see below.
      outHeight - Will be set to the computed value of the height property in the toplevel SVG.
      outHasViewbox - Will be set to TRUE if the toplevel SVG has a viewBox attribute
      outViewbox - Will be set to the value of the viewBox attribute in the toplevel SVG
      Since:
      2.46

    • getIntrinsicSizeInPixels

      public boolean getIntrinsicSizeInPixels(@Nullable Out<Double> outWidth, @Nullable Out<Double> outHeight)

      Converts an SVG document's intrinsic dimensions to pixels, and returns the result.

      This function is able to extract the size in pixels from an SVG document if the document has both width and height attributes with physical units (px, in, cm, mm, pt, pc) or font-based units (em, ex). For physical units, the dimensions are normalized to pixels using the dots-per-inch (DPI) value set previously with setDpi(double). For font-based units, this function uses the computed value of the font-size property for the toplevel <svg> element. In those cases, this function returns TRUE.

      For historical reasons, the default DPI is 90. Current CSS assumes a default DPI of 96, so you may want to set the DPI of a Handle immediately after creating it with setDpi(double).

      This function is not able to extract the size in pixels directly from the intrinsic dimensions of the SVG document if the width or height are in percentage units (or if they do not exist, in which case the SVG spec mandates that they default to 100%), as these require a viewport to be resolved to a final size. In this case, the function returns FALSE.

      For example, the following document fragment has intrinsic dimensions that will resolve to 20x30 pixels.

      <svg xmlns="http://www.w3.org/2000/svg" width="20" height="30"/>

      Similarly, if the DPI is set to 96, this document will resolve to 192×288 pixels (i.e. 96×2 × 96×3).

      <svg xmlns="http://www.w3.org/2000/svg" width="2in" height="3in"/>

      The dimensions of the following documents cannot be resolved to pixels directly, and this function would return FALSE for them:

      <!-- Needs a viewport against which to compute the percentages. -->
<svg xmlns="http://www.w3.org/2000/svg" width="100%" height="100%"/>

<!-- Does not have intrinsic width/height, just a 1:2 aspect ratio which
     needs to be fitted within a viewport. -->
<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 200"/>

      Instead of querying an SVG document's size, applications are encouraged to render SVG documents to a size chosen by the application, by passing a suitably-sized viewport to renderDocument(Context, Rectangle).

      Parameters:
      outWidth - Will be set to the computed width; you should round this up to get integer pixels.
      outHeight - Will be set to the computed height; you should round this up to get integer pixels.
      Returns:
      TRUE if the dimensions could be converted directly to pixels; in this case outWidth and outHeight will be set accordingly. Note that the dimensions are floating-point numbers, so your application can know the exact size of an SVG document. To get integer dimensions, you should use ceil() to round up to the nearest integer (just using round(), may may chop off pixels with fractional coverage). If the dimensions cannot be converted to pixels, returns FALSE and puts 0.0 in both outWidth and outHeight.
      Since:
      2.52

    • getMetadata

      @Deprecated public @Nullable String getMetadata()
      Deprecated.

    • getPixbuf

      @Deprecated public @Nullable Pixbuf getPixbuf()
      Deprecated.
      Use getPixbufAndError().

      Returns the pixbuf loaded by handle. The pixbuf returned will be reffed, so the caller of this function must assume that ref.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      This function depends on the Handle's dots-per-inch value (DPI) to compute the "natural size" of the document in pixels, so you should call setDpi(double) beforehand.

      Returns:
      A pixbuf, or null on error during rendering.

    • getPixbufAndError

      public @Nullable Pixbuf getPixbufAndError() throws GErrorException

      Returns the pixbuf loaded by handle. The pixbuf returned will be reffed, so the caller of this function must assume that ref.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      This function depends on the Handle's dots-per-inch value (DPI) to compute the "natural size" of the document in pixels, so you should call setDpi(double) beforehand.

      Returns:
      A pixbuf, or null on error during rendering.
      Throws:
      GErrorException - see GError
      Since:
      2.59

    • getPixbufSub

      public @Nullable Pixbuf getPixbufSub(@Nullable String id)

      Creates a GdkPixbuf the same size as the entire SVG loaded into handle, but only renders the sub-element that has the specified id (and all its sub-sub-elements recursively). If id is NULL, this function renders the whole SVG.

      This function depends on the Handle's dots-per-inch value (DPI) to compute the "natural size" of the document in pixels, so you should call setDpi(double) beforehand.

      If you need to render an image which is only big enough to fit a particular sub-element of the SVG, consider using renderElement(Context, String, Rectangle).

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Parameters:
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to use the whole SVG.
      Returns:
      a pixbuf, or NULL if an error occurs during rendering.
      Since:
      2.14

    • getPositionSub

      @Deprecated public boolean getPositionSub(PositionData positionData, @Nullable String id)
      Deprecated.
      Use getGeometryForLayer(String, Rectangle, Rectangle, Rectangle) instead. This function is deprecated since it is not able to return exact floating-point positions, only integer pixels.

      Get the position of a subelement of the SVG file. Do not call from within the size_func callback, because an infinite loop will occur.

      This function depends on the Handle's DPI to compute dimensions in pixels, so you should call setDpi(double) beforehand.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      Parameters:
      positionData - A place to store the SVG fragment's position.
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass null to use the whole SVG.
      Returns:
      TRUE if the position could be obtained, FALSE if there was an error.
      Since:
      2.22

    • getTitle

      @Deprecated public @Nullable String getTitle()
      Deprecated.

    • hasSub

      public boolean hasSub(String id)

      Checks whether the element id exists in the SVG document.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      Parameters:
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID.
      Returns:
      TRUE if id exists in the SVG document, FALSE otherwise.
      Since:
      2.22

    • internalSetTesting

      public void internalSetTesting(boolean testing)
      Do not call this function. This is intended for librsvg's internal test suite only.
      Parameters:
      testing - Whether to enable testing mode

    • readStreamSync

      public boolean readStreamSync(InputStream stream, @Nullable Cancellable cancellable) throws GErrorException

      Reads stream and writes the data from it to handle.

      Before calling this function, you may need to call setBaseUri(String) or setBaseGfile(File) to set the "base file" for resolving references to external resources. SVG elements like <image> which reference external resources will be resolved relative to the location you specify with those functions.

      If cancellable is not NULL, then the operation can be cancelled by triggering the cancellable object from another thread. If the operation was cancelled, the error G_IO_ERROR_CANCELLED will be returned.

      Parameters:
      stream - a GInputStream
      cancellable - a GCancellable, or NULL
      Returns:
      TRUE if reading stream succeeded, or FALSE otherwise with error filled in
      Throws:
      GErrorException - see GError
      Since:
      2.32

    • renderCairo

      @Deprecated public boolean renderCairo(org.freedesktop.cairo.Context cr)
      Deprecated.
      Please use renderDocument(Context, Rectangle) instead; that function lets you pass a viewport and obtain a good error message.

      Draws a loaded SVG handle to a Cairo context. Please try to use renderDocument(Context, Rectangle) instead, which allows you to pick the size at which the document will be rendered.

      Historically this function has picked a size by itself, based on the following rules:

      • If the SVG document has both width and height attributes with physical units (px, in, cm, mm, pt, pc) or font-based units (em, ex), the function computes the size directly based on the dots-per-inch (DPI) you have configured with setDpi(double). This is the same approach as getIntrinsicSizeInPixels(Out, Out).

      • Otherwise, if there is a viewBox attribute and both width and height are set to 100% (or if they don't exist at all and thus default to 100%), the function uses the width and height of the viewBox as a pixel size. This produces a rendered document with the correct aspect ratio.

      • Otherwise, this function computes the extents of every graphical object in the SVG document to find the total extents. This is moderately expensive, but no more expensive than rendering the whole document, for example.

      • This function cannot deal with percentage-based units for width and height because there is no viewport against which they could be resolved; that is why it will compute the extents of objects in that case. This is why we recommend that you use renderDocument(Context, Rectangle) instead, which takes in a viewport and follows the sizing policy from the web platform.

      Drawing will occur with respect to the cr's current transformation: for example, if the cr has a rotated current transformation matrix, the whole SVG will be rotated in the rendered version.

      This function depends on the Handle's DPI to compute dimensions in pixels, so you should call setDpi(double) beforehand.

      Note that cr must be a Cairo context that is not in an error state, that is, cairo_status() must return CAIRO_STATUS_SUCCESS for it. Cairo can set a context to be in an error state in various situations, for example, if it was passed an invalid matrix or if it was created for an invalid surface.

      Parameters:
      cr - A Cairo context
      Returns:
      TRUE if drawing succeeded; FALSE otherwise. This function will emit a g_warning() if a rendering error occurs.
      Since:
      2.14

    • renderCairoSub

      @Deprecated public boolean renderCairoSub(org.freedesktop.cairo.Context cr, @Nullable String id)
      Deprecated.
      Please use renderLayer(Context, String, Rectangle) instead; that function lets you pass a viewport and obtain a good error message.

      Renders a single SVG element in the same place as for a whole SVG document (a "subset" of the document). Please try to use renderLayer(Context, String, Rectangle) instead, which allows you to pick the size at which the document with the layer will be rendered.

      This is equivalent to renderCairo(Context), but it renders only a single element and its children, as if they composed an individual layer in the SVG.

      Historically this function has picked a size for the whole document by itself, based on the following rules:

      • If the SVG document has both width and height attributes with physical units (px, in, cm, mm, pt, pc) or font-based units (em, ex), the function computes the size directly based on the dots-per-inch (DPI) you have configured with setDpi(double). This is the same approach as getIntrinsicSizeInPixels(Out, Out).

      • Otherwise, if there is a viewBox attribute and both width and height are set to 100% (or if they don't exist at all and thus default to 100%), the function uses the width and height of the viewBox as a pixel size. This produces a rendered document with the correct aspect ratio.

      • Otherwise, this function computes the extents of every graphical object in the SVG document to find the total extents. This is moderately expensive, but no more expensive than rendering the whole document, for example.

      • This function cannot deal with percentage-based units for width and height because there is no viewport against which they could be resolved; that is why it will compute the extents of objects in that case. This is why we recommend that you use renderLayer(Context, String, Rectangle) instead, which takes in a viewport and follows the sizing policy from the web platform.

      Drawing will occur with respect to the cr's current transformation: for example, if the cr has a rotated current transformation matrix, the whole SVG will be rotated in the rendered version.

      This function depends on the Handle's DPI to compute dimensions in pixels, so you should call setDpi(double) beforehand.

      Note that cr must be a Cairo context that is not in an error state, that is, cairo_status() must return CAIRO_STATUS_SUCCESS for it. Cairo can set a context to be in an error state in various situations, for example, if it was passed an invalid matrix or if it was created for an invalid surface.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      Parameters:
      cr - A Cairo context
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to render the whole SVG.
      Returns:
      TRUE if drawing succeeded; FALSE otherwise. This function will emit a g_warning() if a rendering error occurs.
      Since:
      2.14

    • renderDocument

      public boolean renderDocument(org.freedesktop.cairo.Context cr, Rectangle viewport) throws GErrorException

      Renders the whole SVG document fitted to a viewport.

      The viewport gives the position and size at which the whole SVG document will be rendered. The document is scaled proportionally to fit into this viewport.

      The cr must be in a CAIRO_STATUS_SUCCESS state, or this function will not render anything, and instead will return an error.

      Parameters:
      cr - A Cairo context
      viewport - Viewport size at which the whole SVG would be fitted.
      Returns:

      TRUE on success, FALSE on error. Errors are returned in the error argument.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Throws:
      GErrorException - see GError
      Since:
      2.46

    • renderElement

      public boolean renderElement(org.freedesktop.cairo.Context cr, @Nullable String id, Rectangle elementViewport) throws GErrorException

      Renders a single SVG element to a given viewport.

      This function can be used to extract individual element subtrees and render them, scaled to a given elementViewport. This is useful for applications which have reusable objects in an SVG and want to render them individually; for example, an SVG full of icons that are meant to be be rendered independently of each other.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      You can pass NULL for the id if you want to render all the elements in the SVG, i.e. to render everything from the root element.

      The element_viewport gives the position and size at which the named element will be rendered. FIXME: mention proportional scaling.

      Parameters:
      cr - A Cairo context
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to render the whole SVG document tree.
      elementViewport - Viewport size in which to fit the element
      Returns:

      TRUE on success, FALSE on error. Errors are returned in the error argument.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Throws:
      GErrorException - see GError
      Since:
      2.46

    • renderLayer

      public boolean renderLayer(org.freedesktop.cairo.Context cr, @Nullable String id, Rectangle viewport) throws GErrorException

      Renders a single SVG element in the same place as for a whole SVG document.

      The viewport gives the position and size at which the whole SVG document would be rendered. The document is scaled proportionally to fit into this viewport; hence the individual layer may be smaller than this.

      This is equivalent to renderDocument(Context, Rectangle), but it renders only a single element and its children, as if they composed an individual layer in the SVG. The element is rendered with the same transformation matrix as it has within the whole SVG document. Applications can use this to re-render a single element and repaint it on top of a previously-rendered document, for example.

      Element IDs should look like an URL fragment identifier; for example, pass #foo (hash foo) to get the geometry of the element that has an id="foo" attribute.

      You can pass NULL for the id if you want to render all the elements in the SVG, i.e. to render everything from the root element.

      Parameters:
      cr - A Cairo context
      id - An element's id within the SVG, starting with "" (a single hash character), for example, #layer1. This notation corresponds to a URL's fragment ID. Alternatively, pass NULL to render the whole SVG document tree.
      viewport - Viewport size at which the whole SVG would be fitted.
      Returns:

      TRUE on success, FALSE on error. Errors are returned in the error argument.

      API ordering: This function must be called on a fully-loaded handle. See the section "API ordering" for details.

      Panics: this function will panic if the this Handle is not fully-loaded.

      Throws:
      GErrorException - see GError
      Since:
      2.46

    • setBaseGfile

      public void setBaseGfile(File baseFile)

      Set the base URI for this Handle from file.

      Note: This function may only be called before write(byte[]) or readStreamSync(InputStream, Cancellable) have been called.

      Parameters:
      baseFile - a GFile
      Since:
      2.32

    • setBaseUri

      public void setBaseUri(String baseUri)

      Set the base URI for this SVG.

      Note: This function may only be called before write(byte[]) or readStreamSync(InputStream, Cancellable) have been called.

      Parameters:
      baseUri - The base uri
      Since:
      2.9

    • setCancellableForRendering

      public void setCancellableForRendering(@Nullable Cancellable cancellable)

      Sets a cancellable object that can be used to interrupt rendering while the handle is being rendered in another thread. For example, you can set a cancellable from your main thread, spawn a thread to do the rendering, and interrupt the rendering from the main thread by calling g_cancellable_cancel().

      If rendering is interrupted, the corresponding call to rsvg_handle_render_document() (or any of the other rendering functions) will return an error with domain G_IO_ERROR, and code G_IO_ERROR_CANCELLED.

      Parameters:
      cancellable - A Cancellable or NULL.
      Since:
      2.59.0

    • setDpi

      public void setDpi(double dpi)

      Sets the DPI at which the this Handle will be rendered. Common values are 75, 90, and 300 DPI.

      Passing a number <= 0 to dpi will reset the DPI to whatever the default value happens to be, but since

      invalid reference 
      RsvgsetDefaultDpi
      is deprecated, please

      do not pass values <= 0 to this function.

      Parameters:
      dpi - Dots Per Inch (i.e. as Pixels Per Inch)
      Since:
      2.8

    • setDpiXY

      public void setDpiXY(double dpiX, double dpiY)

      Sets the DPI at which the this Handle will be rendered. Common values are 75, 90, and 300 DPI.

      Passing a number <= 0 to dpi will reset the DPI to whatever the default value happens to be, but since

      invalid reference 
      RsvgsetDefaultDpiXY
      is deprecated,

      please do not pass values <= 0 to this function.

      Parameters:
      dpiX - Dots Per Inch (i.e. Pixels Per Inch)
      dpiY - Dots Per Inch (i.e. Pixels Per Inch)
      Since:
      2.8

    • setSizeCallback

      @Deprecated public void setSizeCallback(@Nullable SizeFunc sizeFunc)
      Deprecated.
      Use renderDocument(Context, Rectangle) instead. This function was deprecated because when the sizeFunc is used, it makes it unclear when the librsvg functions which call the sizeFunc will use the size computed originally, or the callback-specified size, or whether it refers to the whole SVG or to just a sub-element of it. It is easier, and unambiguous, to use code similar to the example above.

      Sets the sizing function for the handle, which can be used to override the size that librsvg computes for SVG images. The sizeFunc is called from the following functions:

      Librsvg computes the size of the SVG being rendered, and passes it to the sizeFunc, which may then modify these values to set the final size of the generated image.

      Parameters:
      sizeFunc - A sizing function, or NULL

    • setStylesheet

      public boolean setStylesheet(@Nullable byte @Nullable [] css) throws GErrorException

      Sets a CSS stylesheet to use for an SVG document.

      The cssLen argument is mandatory; this function will not compute the length of the css string. This is because a provided stylesheet, which the calling program could read from a file, can have nul characters in it.

      During the CSS cascade, the specified stylesheet will be used with a "User" origin.

      Note that @import rules will not be resolved, except for data: URLs.

      Parameters:
      css - String with CSS data; must be valid UTF-8.
      Returns:
      TRUE on success, FALSE on error. Errors are returned in the error argument.
      Throws:
      GErrorException - see GError
      Since:
      2.48

    • write

      @Deprecated public boolean write(@Nullable byte @Nullable [] buf) throws GErrorException
      Deprecated.
      Use readStreamSync(InputStream, Cancellable) or the constructor functions fromGfileSync(File, Set, Cancellable) or fromStreamSync(InputStream, File, Set, Cancellable). This function is deprecated because it will accumulate data from the buf in memory until close() gets called. To avoid a big temporary buffer, use the suggested functions, which take a GFile or a GInputStream and do not require a temporary buffer.

      Loads the next count bytes of the image. You can call this function multiple times until the whole document is consumed; then you must call close() to actually parse the document.

      Before calling this function for the first time, you may need to call setBaseUri(String) or setBaseGfile(File) to set the "base file" for resolving references to external resources. SVG elements like <image> which reference external resources will be resolved relative to the location you specify with those functions.

      Parameters:
      buf - pointer to svg data
      Returns:
      TRUE on success, or FALSE on error.
      Throws:
      GErrorException - see GError

    • builder

      public static Handle.Builder<? extends Handle.Builder> builder()
      A Handle.Builder object constructs a Handle with the specified properties. Use the various set...() methods to set properties, and finish construction with Handle.Builder.build().
      Returns:
      the builder object