GskRenderer: GSK 4 Reference Manual

## GskRenderer GskRenderer — Renders a scene |

## Functions

GskRenderer * | gsk_renderer_new_for_window ()
void | gsk_renderer_set_viewport ()
void | gsk_renderer_get_viewport ()
void | gsk_renderer_set_scale_factor ()
int | gsk_renderer_get_scale_factor ()
GdkWindow * | gsk_renderer_get_window ()
GdkDisplay * | gsk_renderer_get_display ()
gboolean | gsk_renderer_realize ()
void | gsk_renderer_unrealize ()
GdkDrawingContext * | gsk_renderer_begin_draw_frame ()
void | gsk_renderer_end_draw_frame ()
void | gsk_renderer_render ()
GskTexture * | gsk_renderer_render_texture ()

## Properties

GdkDisplay * | display | Read / Write / Construct Only
GdkDrawingContext * | drawing-context | Read
gint | scale-factor | Read / Write
GrapheneRect * | viewport | Read / Write
GdkWindow * | window | Read / Write / Construct Only

## Object Hierarchy

        GObject
        ╰── GskRenderer

## Description

GskRenderer is a class that renders a scene graph defined via a tree of GskRenderNode instances.

Typically you will use a GskRenderer instance with a GdkDrawingContext associated to a GdkWindow, and call `gsk_renderer_render()` with the drawing context and the scene to be rendered.

It is necessary to realize a GskRenderer instance using `gsk_renderer_realize()` before calling `gsk_renderer_render()`, in order to create the appropriate windowing system resources needed to render the scene.

## Functions

### gsk_renderer_new_for_window ()

    GskRenderer *
    gsk_renderer_new_for_window (GdkWindow *window);

Creates an appropriate GskRenderer instance for the given `window` .

The renderer will be realized when it is returned.

#### Parameters

window | a GdkWindow |

#### Returns

a GskRenderer.

[transfer full][nullable]

Since: 3.90

### gsk_renderer_set_viewport ()

    void
    gsk_renderer_set_viewport (GskRenderer *renderer,
                               const graphene_rect_t *viewport);

Sets the visible rectangle to be used as the viewport for the rendering.

#### Parameters

renderer | a GskRenderer |
viewport | the viewport rectangle used by the `renderer` . | [nullable]

Since: 3.90

### gsk_renderer_get_viewport ()

    void
    gsk_renderer_get_viewport (GskRenderer *renderer,
                               graphene_rect_t *viewport);

Retrieves the viewport of the GskRenderer.

#### Parameters

renderer | a GskRenderer |
viewport | return location for the viewport rectangle. | [out caller-allocates]

Since: 3.90

### gsk_renderer_set_scale_factor ()

    void
    gsk_renderer_set_scale_factor (GskRenderer *renderer,
                                   int scale_factor);

Sets the scale factor for the renderer.

#### Parameters

renderer | a GskRenderer |
scale_factor | the new scale factor |

Since: 3.90

### gsk_renderer_get_scale_factor ()

    int
    gsk_renderer_get_scale_factor (GskRenderer *renderer);

Gets the scale factor for the `renderer` .

#### Parameters

renderer | a GskRenderer |

#### Returns

the scale factor

Since: 3.90

### gsk_renderer_get_window ()

    GdkWindow *
    gsk_renderer_get_window (GskRenderer *renderer);

Retrieves the GdkWindow set using `gsk_renderer_realize()`. If the renderer has not been realized yet, `NULL` will be returned.

#### Parameters

renderer | a GskRenderer |

#### Returns

a GdkWindow.

[transfer none][nullable]

Since: 3.90

### gsk_renderer_get_display ()

    GdkDisplay *
    gsk_renderer_get_display (GskRenderer *renderer);

Retrieves the GdkDisplay used when creating the GskRenderer.

#### Parameters

renderer | a GskRenderer |

#### Returns

a GdkDisplay.

[transfer none]

Since: 3.90

### gsk_renderer_realize ()

    gboolean
    gsk_renderer_realize (GskRenderer *renderer,
                          GdkWindow *window,
                          GError **error);

Creates the resources needed by the `renderer` to render the scene graph.

#### Parameters

renderer | a GskRenderer |
window | the GdkWindow renderer will be used on |
error | return location for an error |

Since: 3.90

### gsk_renderer_unrealize ()

    void
    gsk_renderer_unrealize (GskRenderer *renderer);

Releases all the resources created by `gsk_renderer_realize()`.

#### Parameters

renderer | a GskRenderer |

Since: 3.90

### gsk_renderer_begin_draw_frame ()

    GdkDrawingContext *
    gsk_renderer_begin_draw_frame (GskRenderer *renderer,
                                   const cairo_region_t *region);

Indicates that you are beginning the process of redrawing `region` using `renderer` , and provides you with a GdkDrawingContext to use for this.

#### Parameters

renderer | a GskRenderer |
region | the cairo_region_t that you wish to draw |

#### Returns

a GdkDrawingContext context that should be used to draw the contents of the `renderer` . This context is owned by GDK.

[transfer none]

Since: 3.90

### gsk_renderer_end_draw_frame ()

    void
    gsk_renderer_end_draw_frame (GskRenderer *renderer,
                                 GdkDrawingContext *context);

### gsk_renderer_render ()

    void
    gsk_renderer_render (GskRenderer *renderer,
                         GskRenderNode *root,
                         GdkDrawingContext *context);

Renders the scene graph, described by a tree of GskRenderNode instances, using the given GdkDrawingContext.

The `renderer` will acquire a reference on the GskRenderNode tree while the rendering is in progress.

#### Parameters

renderer | a GskRenderer |
root | a GskRenderNode |
context | The drawing context created via `gsk_renderer_begin_draw_frame()` |

Since: 3.90

### gsk_renderer_render_texture ()

    GskTexture *
    gsk_renderer_render_texture (GskRenderer *renderer,
                                 GskRenderNode *root,
                                 const graphene_rect_t *viewport);

Renders the scene graph, described by a tree of GskRenderNode instances, to a GskTexture.

The `renderer` will acquire a reference on the GskRenderNode tree while the rendering is in progress, and will make the tree immutable.

If you want to apply any transformations to `root` , you should put it into a transform node and pass that node instead.

#### Parameters

renderer | a realized GdkRenderer |
root | a GskRenderNode |
viewport | the section to draw or `NULL` to use `root` 's bounds. | [allow-none]

#### Returns

a GskTexture with the rendered contents of `root` .

[transfer full]

Since: 3.90

## Types and Values

## Property Details

### The `“display”` property

      “display”                  GdkDisplay *

The GdkDisplay used by the GskRenderer.

Flags: Read / Write / Construct Only

Since: 3.90

### The `“drawing-context”` property

      “drawing-context”          GdkDrawingContext *

The drawing context used when rendering.

Flags: Read

Since: 3.90

### The `“scale-factor”` property

      “scale-factor”             gint

The scale factor used when rendering.

Flags: Read / Write

Allowed values: >= 1

Default value: 1

Since: 3.90

### The `“viewport”` property

      “viewport”                 GrapheneRect *

The visible area used by the GskRenderer to render its contents.

Flags: Read / Write

Since: 3.90

### The `“window”` property

      “window”                   GdkWindow *

The window associated to the renderer.

Flags: Read / Write / Construct Only