CanvasItem

Inherits: Node < Object

Inherited By: Control, Node2D

Base class of anything 2D.

Description

Base class of anything 2D. Canvas items are laid out in a tree; children inherit and extend their parent’s transform. CanvasItem is extended by Control for anything GUI-related, and by Node2D for anything related to the 2D engine.

Any CanvasItem can draw. For this, update must be called, then NOTIFICATION_DRAW will be received on idle time to request redraw. Because of this, canvas items don’t need to be redrawn on every frame, improving the performance significantly. Several functions for drawing on the CanvasItem are provided (see draw_* functions). However, they can only be used inside the Object._notification, signal or _draw virtual functions.

Canvas items are drawn in tree order. By default, children are on top of their parents so a root CanvasItem will be drawn behind everything. This behavior can be changed on a per-item basis.

A CanvasItem can also be hidden, which will also hide its children. It provides many ways to change parameters such as modulation (for itself and its children) and self modulation (only for itself), as well as its blend mode.

Ultimately, a transform notification can be requested, which will notify the node that its global position changed in case the parent tree changed.

Note: Unless otherwise specified, all methods that have angle parameters must have angles specified as radians. To convert degrees to radians, use @GDScript.deg2rad.

Properties

int light_mask 1
Material material  
Color modulate Color( 1, 1, 1, 1 )
Color self_modulate Color( 1, 1, 1, 1 )
bool show_behind_parent false
bool show_on_top  
bool use_parent_material false
bool visible true

Methods

void _draw ( ) virtual
void draw_arc ( Vector2 center, float radius, float start_angle, float end_angle, int point_count, Color color, float width=1.0, bool antialiased=false )
float draw_char ( Font font, Vector2 position, String char, String next, Color modulate=Color( 1, 1, 1, 1 ) )
void draw_circle ( Vector2 position, float radius, Color color )
void draw_colored_polygon ( PoolVector2Array points, Color color, PoolVector2Array uvs=PoolVector2Array( ), Texture texture=null, Texture normal_map=null, bool antialiased=false )
void draw_line ( Vector2 from, Vector2 to, Color color, float width=1.0, bool antialiased=false )
void draw_mesh ( Mesh mesh, Texture texture, Texture normal_map=null, Transform2D transform=Transform2D( 1, 0, 0, 1, 0, 0 ), Color modulate=Color( 1, 1, 1, 1 ) )
void draw_multiline ( PoolVector2Array points, Color color, float width=1.0, bool antialiased=false )
void draw_multiline_colors ( PoolVector2Array points, PoolColorArray colors, float width=1.0, bool antialiased=false )
void draw_multimesh ( MultiMesh multimesh, Texture texture, Texture normal_map=null )
void draw_polygon ( PoolVector2Array points, PoolColorArray colors, PoolVector2Array uvs=PoolVector2Array( ), Texture texture=null, Texture normal_map=null, bool antialiased=false )
void draw_polyline ( PoolVector2Array points, Color color, float width=1.0, bool antialiased=false )
void draw_polyline_colors ( PoolVector2Array points, PoolColorArray colors, float width=1.0, bool antialiased=false )
void draw_primitive ( PoolVector2Array points, PoolColorArray colors, PoolVector2Array uvs, Texture texture=null, float width=1.0, Texture normal_map=null )
void draw_rect ( Rect2 rect, Color color, bool filled=true, float width=1.0, bool antialiased=false )
void draw_set_transform ( Vector2 position, float rotation, Vector2 scale )
void draw_set_transform_matrix ( Transform2D xform )
void draw_string ( Font font, Vector2 position, String text, Color modulate=Color( 1, 1, 1, 1 ), int clip_w=-1 )
void draw_style_box ( StyleBox style_box, Rect2 rect )
void draw_texture ( Texture texture, Vector2 position, Color modulate=Color( 1, 1, 1, 1 ), Texture normal_map=null )
void draw_texture_rect ( Texture texture, Rect2 rect, bool tile, Color modulate=Color( 1, 1, 1, 1 ), bool transpose=false, Texture normal_map=null )
void draw_texture_rect_region ( Texture texture, Rect2 rect, Rect2 src_rect, Color modulate=Color( 1, 1, 1, 1 ), bool transpose=false, Texture normal_map=null, bool clip_uv=true )
void force_update_transform ( )
RID get_canvas ( ) const
RID get_canvas_item ( ) const
Transform2D get_canvas_transform ( ) const
Vector2 get_global_mouse_position ( ) const
Transform2D get_global_transform ( ) const
Transform2D get_global_transform_with_canvas ( ) const
Vector2 get_local_mouse_position ( ) const
Transform2D get_transform ( ) const
Rect2 get_viewport_rect ( ) const
Transform2D get_viewport_transform ( ) const
World2D get_world_2d ( ) const
void hide ( )
bool is_local_transform_notification_enabled ( ) const
bool is_set_as_toplevel ( ) const
bool is_transform_notification_enabled ( ) const
bool is_visible_in_tree ( ) const
Vector2 make_canvas_position_local ( Vector2 screen_point ) const
InputEvent make_input_local ( InputEvent event ) const
void set_as_toplevel ( bool enable )
void set_notify_local_transform ( bool enable )
void set_notify_transform ( bool enable )
void show ( )
void update ( )

Signals

  • draw ( )

Emitted when the CanvasItem must redraw. This can only be connected realtime, as deferred will not allow drawing.

  • hide ( )

Emitted when becoming hidden.

  • item_rect_changed ( )

Emitted when the item rect has changed.

  • visibility_changed ( )

Emitted when the visibility (hidden/visible) changes.

Enumerations

enum BlendMode:

  • BLEND_MODE_MIX = 0 — Mix blending mode. Colors are assumed to be independent of the alpha (opacity) value.
  • BLEND_MODE_ADD = 1 — Additive blending mode.
  • BLEND_MODE_SUB = 2 — Subtractive blending mode.
  • BLEND_MODE_MUL = 3 — Multiplicative blending mode.
  • BLEND_MODE_PREMULT_ALPHA = 4 — Mix blending mode. Colors are assumed to be premultiplied by the alpha (opacity) value.
  • BLEND_MODE_DISABLED = 5 — Disables blending mode. Colors including alpha are written as-is. Only applicable for render targets with a transparent background. No lighting will be applied.

Constants

  • NOTIFICATION_TRANSFORM_CHANGED = 2000 — The CanvasItem’s transform has changed. This notification is only received if enabled by set_notify_transform or set_notify_local_transform.
  • NOTIFICATION_DRAW = 30 — The CanvasItem is requested to draw.
  • NOTIFICATION_VISIBILITY_CHANGED = 31 — The CanvasItem’s visibility has changed.
  • NOTIFICATION_ENTER_CANVAS = 32 — The CanvasItem has entered the canvas.
  • NOTIFICATION_EXIT_CANVAS = 33 — The CanvasItem has exited the canvas.

Property Descriptions

  • int light_mask
Default 1
Setter set_light_mask(value)
Getter get_light_mask()

The rendering layers in which this CanvasItem responds to Light2D nodes.

Setter set_material(value)
Getter get_material()

The material applied to textures on this CanvasItem.

Default Color( 1, 1, 1, 1 )
Setter set_modulate(value)
Getter get_modulate()

The color applied to textures on this CanvasItem.

Default Color( 1, 1, 1, 1 )
Setter set_self_modulate(value)
Getter get_self_modulate()

The color applied to textures on this CanvasItem. This is not inherited by children CanvasItems.

  • bool show_behind_parent
Default false
Setter set_draw_behind_parent(value)
Getter is_draw_behind_parent_enabled()

If true, the object draws behind its parent.

If true, the object draws on top of its parent.

  • bool use_parent_material
Default false
Setter set_use_parent_material(value)
Getter get_use_parent_material()

If true, the parent CanvasItem’s material property is used as this one’s material.

Default true
Setter set_visible(value)
Getter is_visible()

If true, this CanvasItem is drawn. For controls that inherit Popup, the correct way to make them visible is to call one of the multiple popup*() functions instead.

Method Descriptions

  • void _draw ( ) virtual

Overridable function called by the engine (if defined) to draw the canvas item.

Draws an arc between the given angles. The larger the value of point_count, the smoother the curve.

Draws a string character using a custom font. Returns the advance, depending on the character width and kerning with an optional next character.

Draws a colored circle.

Draws a colored polygon of any amount of points, convex or concave.

Draws a line from a 2D point to another, with a given color and width. It can be optionally antialiased.

Draws a Mesh in 2D, using the provided texture. See MeshInstance2D for related documentation.

Draws multiple, parallel lines with a uniform color. width and antialiased are currently not implemented and have no effect.

Draws multiple, parallel lines with a uniform width, segment-by-segment coloring, and optional antialiasing. Colors assigned to line segments match by index between points and colors.

Draws a MultiMesh in 2D with the provided texture. See MultiMeshInstance2D for related documentation.

Draws a polygon of any amount of points, convex or concave.

Draws interconnected line segments with a uniform color and width and optional antialiasing.

Draws interconnected line segments with a uniform width, segment-by-segment coloring, and optional antialiasing. Colors assigned to line segments match by index between points and colors.

Draws a custom primitive. 1 point for a point, 2 points for a line, 3 points for a triangle and 4 points for a quad.

Draws a rectangle. If filled is true, the rectangle will be filled with the color specified. If filled is false, the rectangle will be drawn as a stroke with the color and width specified. If antialiased is true, the lines will be antialiased.

Note: width and antialiased are only effective if filled is false.

Sets a custom transform for drawing via components. Anything drawn afterwards will be transformed by this.

Sets a custom transform for drawing via matrix. Anything drawn afterwards will be transformed by this.

Draws a string using a custom font.

Draws a styled rectangle.

Draws a texture at a given position.

Draws a textured rectangle at a given position, optionally modulated by a color. If transpose is true, the texture will have its X and Y coordinates swapped.

Draws a textured rectangle region at a given position, optionally modulated by a color. If transpose is true, the texture will have its X and Y coordinates swapped.

  • void force_update_transform ( )

Forces the transform to update. Transform changes in physics are not instant for performance reasons. Transforms are accumulated and then set. Use this if you need an up-to-date transform when doing physics operations.

  • RID get_canvas ( ) const

Returns the RID of the World2D canvas where this item is in.

  • RID get_canvas_item ( ) const

Returns the canvas item RID used by VisualServer for this item.

Returns the transform matrix of this item’s canvas.

  • Vector2 get_global_mouse_position ( ) const

Returns the global position of the mouse.

Returns the global transform matrix of this item.

  • Transform2D get_global_transform_with_canvas ( ) const

Returns the global transform matrix of this item in relation to the canvas.

  • Vector2 get_local_mouse_position ( ) const

Returns the mouse position relative to this item’s position.

Returns the transform matrix of this item.

  • Rect2 get_viewport_rect ( ) const

Returns the viewport’s boundaries as a Rect2.

Returns this item’s transform in relation to the viewport.

Returns the World2D where this item is in.

  • void hide ( )

Hide the CanvasItem if it’s currently visible.

  • bool is_local_transform_notification_enabled ( ) const

Returns true if local transform notifications are communicated to children.

  • bool is_set_as_toplevel ( ) const

Returns true if the node is set as top-level. See set_as_toplevel.

  • bool is_transform_notification_enabled ( ) const

Returns true if global transform notifications are communicated to children.

  • bool is_visible_in_tree ( ) const

Returns true if the node is present in the SceneTree, its visible property is true and its inherited visibility is also true.

Assigns screen_point as this node’s new local transform.

Transformations issued by event’s inputs are applied in local space instead of global space.

  • void set_as_toplevel ( bool enable )

If enable is true, the node won’t inherit its transform from parent canvas items.

  • void set_notify_local_transform ( bool enable )

If enable is true, children will be updated with local transform data.

  • void set_notify_transform ( bool enable )

If enable is true, children will be updated with global transform data.

  • void show ( )

Show the CanvasItem if it’s currently hidden. For controls that inherit Popup, the correct way to make them visible is to call one of the multiple popup*() functions instead.

  • void update ( )

Queue the CanvasItem for update. NOTIFICATION_DRAW will be called on idle time to request redraw.