simvx.core.nodes_2d.background_bands

BackgroundBands / SkyHorizon: horizontal colour bands relative to the camera.

Renders a stack of full-width horizontal stripes that fill the visible viewport. Useful for sky / sea / cave-tier backdrops where you want a few solid bands (or gradient bands) without authoring a backdrop texture.

Two scroll modes:

• world_space=True (default): bands are anchored at fixed world-Y values: the camera can scroll past them, so a “horizon” stays put.

• world_space=False: bands lock to the screen: the sky always stays at the top of the viewport, irrespective of camera Y. Equivalent to parenting a Node2D under a CanvasLayer.

A band entry is (top_y, colour, [bottom_colour]):

• top_y: Y in the chosen space (world or screen) for the top of this band. Bands are sorted ascending; each band extends down to the next band’s top_y (or the viewport bottom for the last band).

• colour: solid RGBA fill, or top colour for a vertical gradient.

• bottom_colour: optional; if given, the band is a vertical gradient from colour (top) to bottom_colour (bottom).

Module Contents

Classes

BackgroundBands

Horizontal colour bands that follow the camera.

Data

Band

API

simvx.core.nodes_2d.background_bands.Band

None

class simvx.core.nodes_2d.background_bands.BackgroundBands(bands: collections.abc.Sequence[simvx.core.nodes_2d.background_bands.Band] | None = None, world_space: bool = True, **kwargs)

Bases: simvx.core.nodes_2d.node2d.Node2D

Horizontal colour bands that follow the camera.

Example: sky / sea horizon at world-Y = 0::

bg = root.add_child(BackgroundBands())
bg.bands = [
    (-1e9, (0.4, 0.7, 1.0, 1.0), (0.7, 0.85, 1.0, 1.0)),  # sky
    (0.0,  (0.1, 0.3, 0.6, 1.0), (0.05, 0.15, 0.4, 1.0)),  # sea
]

Initialization

world_space

‘Property(…)’

property bands: list[simvx.core.nodes_2d.background_bands.Band]

add_band(top_y: float, colour: tuple[float, ...], bottom_colour: tuple[float, ...] | None = None) → None

Append a band entry. Bands are sorted by top_y at draw time.

clear_bands() → None

on_draw(renderer) → None

Emit the band rects covering the visible viewport.

position

‘_SpatialVecProperty(…)’

rotation

‘Property(…)’

scale

‘_SpatialVecProperty(…)’

z_index

‘Property(…)’

z_as_relative

‘Property(…)’

render_layer

‘Property(…)’

set_render_layer(index: int, enabled: bool = True) → None

is_on_render_layer(index: int) → bool

property absolute_z_index: int

property rotation_degrees: float

property world_position: simvx.core.math.types.Vec2

property world_rotation: float

property world_scale: simvx.core.math.types.Vec2

property world_transform: tuple[simvx.core.math.types.Vec2, simvx.core.math.types.Vec2, float]

property forward: simvx.core.math.types.Vec2

property right: simvx.core.math.types.Vec2

translate(offset: tuple[float, float] | numpy.ndarray)

rotate(radians: float)

rotate_deg(degrees: float)

look_at(target: tuple[float, float] | numpy.ndarray)

transform_points(points: list[simvx.core.math.types.Vec2]) → list[simvx.core.math.types.Vec2]

draw_polygon(renderer, points: list[simvx.core.math.types.Vec2], closed=True, colour=None)

wrap_screen(margin: float = 20)

strict_errors: ClassVar[bool]

True

script_error_raised

‘Signal(…)’

classmethod __init_subclass__(**kwargs)

property name: str

property process_mode: simvx.core.descriptors.ProcessMode

property visible: bool

reset_error() → None

add_child(node: simvx.core.node.Node) → simvx.core.node.Node

remove_child(node: simvx.core.node.Node)

reparent(new_parent: simvx.core.node.Node)

get_node(path: str) → simvx.core.node.Node

find_child(name: str, recursive: bool = False) → simvx.core.node.Node | None

find(target: type | str, recursive: bool = True) → simvx.core.node.Node | None

find_all(node_type: type, recursive: bool = True) → list

walk(*, include_self: bool = True) → collections.abc.Iterator[simvx.core.node.Node]

property path: str

add_to_group(group: str)

remove_from_group(group: str)

is_in_group(group: str) → bool

on_ready() → None

on_enter_tree() → None

on_exit_tree() → None

on_process(dt: float) → None

on_physics_process(dt: float) → None

on_picked(event: simvx.core.events.InputEvent) → None

on_unhandled_input(event: simvx.core.events.TreeInputEvent) → None

start_coroutine(gen: simvx.core.descriptors.Coroutine) → simvx.core.descriptors.CoroutineHandle

stop_coroutine(gen_or_handle)

clear_children()

destroy()

property app

property tree: simvx.core.scene_tree.SceneTree

__getitem__(key: str)

classmethod get_properties() → dict[str, simvx.core.descriptors.Property]

__repr__()