Class RenderNode

java.lang.Object
org.javagi.base.ProxyInstance
org.gnome.gobject.TypeInstance
org.gnome.gsk.RenderNode
All Implemented Interfaces:
Proxy
Direct Known Subclasses:
BlendNode, BlurNode, BorderNode, CairoNode, ClipNode, ColorMatrixNode, ColorNode, ComponentTransferNode, CompositeNode, ConicGradientNode, ContainerNode, CopyNode, CrossFadeNode, DebugNode, FillNode, GLShaderNode, InsetShadowNode, IsolationNode, LinearGradientNode, MaskNode, OpacityNode, OutsetShadowNode, PasteNode, RadialGradientNode, RenderNode.RenderNode$Impl, RepeatingLinearGradientNode, RepeatingRadialGradientNode, RepeatNode, RoundedClipNode, ShadowNode, StrokeNode, SubsurfaceNode, TextNode, TextureNode, TextureScaleNode, TransformNode
@Generated("org.javagi.JavaGI") public abstract class RenderNode extends TypeInstance

The basic block in a scene graph to be rendered using Renderer.

Each node has a parent, except the top-level node; each node may have children nodes.

Each node has an associated drawing surface, which has the size of the rectangle set when creating it.

Render nodes are meant to be transient; once they have been associated to a Renderer it's safe to release any reference you have on them. All RenderNodes are immutable, you can only specify their properties during construction.

  • Constructor Details

    • RenderNode

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

  • Method Details

    • getType

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

    • getMemoryLayout

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

    • asParent

      protected RenderNode 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.
      Returns:
      the instance as if it were its parent type

    • deserialize

      public static @Nullable RenderNode deserialize(byte[] bytes, @Nullable ParseErrorFunc errorFunc)

      Loads data previously created via serialize().

      For a discussion of the supported format, see that function.

      Parameters:
      bytes - the bytes containing the data
      errorFunc - callback on parsing errors
      Returns:
      a new render node

    • draw

      public void draw(org.freedesktop.cairo.Context cr)

      Draws the contents of a render node on a cairo context.

      Typically, you'll use this function to implement fallback rendering of render nodes on an intermediate Cairo context, instead of using the drawing context associated to a Surface's rendering buffer.

      For advanced nodes that cannot be supported using Cairo, in particular for nodes doing 3D operations, this function may fail.

      Parameters:
      cr - cairo context to draw to

    • getBounds

      public void getBounds(Rect bounds)

      Retrieves the boundaries of the node.

      The node will not draw outside of its boundaries.

      Parameters:
      bounds - return location for the boundaries

    • getChildren

      public @Nullable RenderNode @Nullable [] getChildren()

      Gets a list of all children nodes of the rendernode.

      Keep in mind that for various rendernodes, their children have different semantics, like the mask vs the source of a mask node. If you care about thse semantics, don't use this function, use the specific getters instead.

      Returns:
      The children
      Since:
      4.22

    • getNodeType

      public RenderNodeType getNodeType()
      Returns the type of the render node.
      Returns:
      the type of this RenderNode

    • getOpaqueRect

      public boolean getOpaqueRect(Rect outOpaque)

      Gets an opaque rectangle inside the node that GTK can determine to be fully opaque.

      There is no guarantee that this is indeed the largest opaque rectangle or that regions outside the rectangle are not opaque. This function is a best effort with that goal.

      The rectangle will be fully contained in the bounds of the node.

      Parameters:
      outOpaque - return location for the opaque rect
      Returns:
      true if part or all of the rendernode is opaque, false if no opaque region could be found.
      Since:
      4.16

    • ref

      public RenderNode ref()
      Acquires a reference on the given GskRenderNode.
      Returns:
      the render node with an additional reference

    • serialize

      public byte[] serialize()

      Serializes the this RenderNode for later deserialization via gsk_render_node_deserialize(). No guarantees are made about the format used other than that the same version of GTK will be able to deserialize the result of a call to gsk_render_node_serialize() and gsk_render_node_deserialize() will correctly reject files it cannot open that were created with previous versions of GTK.

      The intended use of this functions is testing, benchmarking and debugging. The format is not meant as a permanent storage format.

      Returns:
      a GBytes representing the node.

    • unref

      public void unref()

      Releases a reference on the given GskRenderNode.

      If the reference was the last, the resources associated to the this RenderNode are freed.

    • writeToFile

      public boolean writeToFile(String filename) throws GErrorException

      This function is equivalent to calling serialize() followed by GLib#fileSetContents.

      See those two functions for details on the arguments.

      It is mostly intended for use inside a debugger to quickly dump a render node to a file for later inspection.

      Parameters:
      filename - the file to save it to
      Returns:
      true if saving was successful
      Throws:
      GErrorException - see GError