Nineslice

Based on game build 714014 | Last updated: 2026-03-08

Overview

NineSlice is a UI widget that implements nine-slice scaling, a technique used to scale rectangular textures (such as buttons or panels) without distorting corners and edges. It creates eight surrounding sub-elements arranged around a central mid_center element, which acts as the reference for sizing and alignment. This component extends Widget and is intended for client-side UI rendering only.

Usage example

local nineslice = TheWidgetManager:AddChild(NineSlice("images/myatlas.xml",
    "topleft.tex", "top.tex", "topright.tex",
    "left.tex", "center.tex", "right.tex",
    "bottomleft.tex", "bottom.tex", "bottomright.tex"))

nineslice:SetSize(200, 100)
nineslice:SetTint(1, 1, 1, 0.8)

Dependencies & tags

Components used: None identified.
Tags: None identified.

Properties

Property	Type	Default Value	Description
atlas	string or nil	nil	Texture atlas used for all sub-elements.
mid_center	Image or Widget	nil	Central element used as the sizing and alignment anchor.
elements	table of Image	{}	Array of all eight surrounding sub-elements (corners, edges, and center edges).

Main functions

SetSize(w, h)

• Description: Sets the size of the nine-slice widget by resizing and repositioning all sub-elements relative to the mid_center element.
• Parameters:
  • w (number) — width in pixels.
  • h (number) — height in pixels.
• Returns: Nothing.

SetScale(w, h)

• Description: Applies scaling to all sub-elements without changing their actual size, useful for zooming or resolution adjustments.
• Parameters:
  • w (number) — horizontal scale factor.
  • h (number) — vertical scale factor.
• Returns: Nothing.

AddCrown(image, hanchor, vanchor, offsetX, offsetY)

• Description: Adds a new image element (a "crown") at the specified anchor point, which is appended to the internal elements array and will scale/position with the widget.
• Parameters:
  • image (string) — texture name within the atlas.
  • hanchor (number) — horizontal anchor constant (e.g., ANCHOR_LEFT).
  • vanchor (number) — vertical anchor constant (e.g., ANCHOR_TOP).
  • offsetX (number, optional) — horizontal offset in pixels. Default: 0.
  • offsetY (number, optional) — vertical offset in pixels. Default: 0.
• Returns: The created Image instance.

AddTail(image, hanchor, vanchor, offsetX, offsetY)

• Description: Adds a special "tail" image element, stored separately as self.tail but also added to self.elements.
• Parameters: Same as AddCrown.
• Returns: The created Image instance.

UpdateTail(hanchor, vanchor, offsetX, offsetY)

• Description: Updates the positioning and anchor of the tail element, useful for dynamic repositioning after creation.
• Parameters: Same as AddCrown.
• Returns: Nothing.

SetTint(r, g, b, a)

• Description: Applies a color tint to the entire nine-slice, affecting both mid_center and all elements in self.elements.
• Parameters:
  • r (number) — red component (0–1).
  • g (number) — green component (0–1).
  • b (number) — blue component (0–1).
  • a (number) — alpha (opacity) component (0–1).
• Returns: Nothing.

GetSize()

• Description: Returns the current size of the widget, as defined by mid_center.
• Parameters: None.
• Returns:
  • w (number) — current width.
  • h (number) — current height.

DebugDraw_AddSection(dbui, panel)

• Description: Adds debug UI controls for editing the widget size interactively during development.
• Parameters:
  • dbui (DebugUI instance) — UI builder interface.
  • panel (Panel) — parent debug panel.
• Returns: Nothing.

Events & listeners

None identified.