ObjectDragShapePreview

Live shape indicator for object multi-cell drags (LINE, RECTANGLE_FILL, RECTANGLE_OUTLINE). Terrain brushes already ghost the full pending shape while dragging (TerrainPreview); object drags previously showed only the single cursor ghost, so the area a release stamps was invisible. This node draws the pending shape from the session brush state's drag start to the live cursor cell: the exact generated cell path for LINE, a map-aligned polygon for rectangle shapes, and translucent fill only for RECTANGLE_FILL. On top of the span geometry, the overlay marks the ordered-simulation candidates: each shape cell, in commit order, whose footprint rect is anchored on mapped tile data and free of committed records plus already-accepted cells. Only these cells get placement markers, so a multi-cell drag shows the sparse subset it will actually stamp. Full rules still gate each commit, so commit results are always a subset of the preview — never more. The OBJECT_GHOSTS style draws a translucent copy of the live preview's sprites on those same cells instead of the square markers, which read badly on isometric maps. Wiring: place one under World next to TerrainPreview. The host binder calls resolve_placement_runtime(host, session); the node then polls the session brush lifecycle every physics frame and hides itself whenever no object drag is active, so release, cancel, mode-exit, and session paths need no explicit teardown calls. 2D GRID TileMapLayer sessions only: without a target map (3D sessions) the node stays hidden.

Source: addons/grid_placement/systems/building/object_drag_shape_preview.gd

Syntax

class ObjectDragShapePreview extends RefCounted

Members

Name	Kind	Summary
PREVIEW_GROUP	Field	Scene-tree group so the host or tools can refresh all shape previews.
FALLBACK_OUTLINE	Field	Fallback outline color when no highlight settings resolve.
FILL_ALPHA	Field	Fill alpha applied over the resolved outline color.
kind	Property	Draw geometry for one drag frame. [member kind] is &"line", &"rect", or &"none"; [member points] and [member rect] are world space.
points	Property
rect	Property	World-space AABB of [member points].
fill	Property	True only for RECTANGLE_FILL.
accepted_cells	Property	Ordered-simulation candidates, in commit order.
accepted_rects	Property	World footprint rects, parallel to [member accepted_cells].
current_cell	Property	The live cursor cell (where the live preview already draws).
style	Property	The resolved [enum PlacementSettings.DragGhostStyle].
is_none	Method
draws_same_as	Method
SIM_REFRESH_INTERVAL_TICKS	Field
resolve_placement_dependencies	Method
resolve_placement_runtime	Method
request_refresh	Method
update_preview	Method
get_last_geometry	Method
is_shape_visible	Method
empty	Property
service	Property
entry	Property
coordinator	Property
cap	Property
placement_budget	Property
settings	Property
tile_size	Property
placement_cap	Property
preview	Property
rotation	Property
states	Property
placed_count	Property
tick	Property
key	Property
cells	Property
result	Property
geometry_for_cells	Method
none	Property
line_cells	Property
line_points	Property
min_cell	Property
max_cell	Property
corners	Property
basis_x	Property
basis_y	Property
basis_x	Property
basis_y	Property
top_left	Property
top_right	Property
bottom_right	Property
bottom_left	Property
outline	Property