Gsk.RenderNode

Subclasses:

Gsk.BlendNode, Gsk.BlurNode, Gsk.BorderNode, Gsk.CairoNode, Gsk.ClipNode, Gsk.ColorMatrixNode, Gsk.ColorNode, Gsk.ConicGradientNode, Gsk.ContainerNode, Gsk.CrossFadeNode, Gsk.DebugNode, Gsk.GLShaderNode, Gsk.InsetShadowNode, Gsk.LinearGradientNode, Gsk.MaskNode, Gsk.OpacityNode, Gsk.OutsetShadowNode, Gsk.RadialGradientNode, Gsk.RepeatNode, Gsk.RepeatingLinearGradientNode, Gsk.RepeatingRadialGradientNode, Gsk.RoundedClipNode, Gsk.ShadowNode, Gsk.TextNode, Gsk.TextureNode, Gsk.TextureScaleNode, Gsk.TransformNode

Methods

class	deserialize (bytes, error_func, *user_data)
	draw (cr)
	get_bounds ()
	get_node_type ()
	ref ()
	serialize ()
	unref ()
	write_to_file (filename)

Virtual Methods

None

Fields

None

Class Details

class Gsk.RenderNode

Abstract:

Yes

GskRenderNode is the basic block in a scene graph to be rendered using [class`Gsk`.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 [class`Gsk`.Renderer] it’s safe to release any reference you have on them. All [class`Gsk`.RenderNode]s are immutable, you can only specify their properties during construction.

classmethod deserialize(bytes, error_func, *user_data)

Parameters:

• bytes (GLib.Bytes) – the bytes containing the data

• error_func (Gsk.ParseErrorFunc or None) – Callback on parsing errors

• user_data (object or None) – user_data for error_func

Returns:

a new GskRenderNode

Return type:

Gsk.RenderNode or None

Loads data previously created via [method`Gsk`.RenderNode.serialize].

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

draw(cr)

Parameters:

cr (cairo.Context) – cairo context to draw to

Draw the contents of self to the given cairo context.

Typically, you’ll use this function to implement fallback rendering of ``GskRenderNode``s on an intermediate Cairo context, instead of using the drawing context associated to a [class`Gdk`.Surface]’s rendering buffer.

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

get_bounds()

Returns:

return location for the boundaries

Return type:

bounds: Graphene.Rect

Retrieves the boundaries of the self.

The node will not draw outside of its boundaries.

get_node_type()

Returns:

the type of the GskRenderNode

Return type:

Gsk.RenderNodeType

Returns the type of the self.

ref()

Returns:

the GskRenderNode with an additional reference

Return type:

Gsk.RenderNode

Acquires a reference on the given GskRenderNode.

serialize()

Returns:

a GBytes representing the node.

Return type:

GLib.Bytes

Serializes the self for later deserialization via Gsk.RenderNode.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.RenderNode.serialize() and Gsk.RenderNode.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.

unref()

Releases a reference on the given GskRenderNode.

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

write_to_file(filename)

Parameters:

filename (str) – the file to save it to.

Raises:

GLib.Error

Returns:

True if saving was successful

Return type:

bool

This function is equivalent to calling [method`Gsk`.RenderNode.serialize] followed by [func`GLib`.file_set_contents].

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.