UI Operations

CreateUICanvas

Create a UI canvas entity — the root of a UI hierarchy. All UI elements must be descendants of a canvas.

Parameter	Type	Required	Description
canvas_name	string	Yes	Canvas entity name
render_mode	string	No	"screen_space" (HUD/menus), "world_space" (3D positioned), or "render_to_texture"
sort_order	integer	No	Render order for multiple canvases (higher = on top, default: 0)
parent_guid	string	No	Parent entity GUID

{
  "op": "CreateUICanvas",
  "params": {
    "canvas_name": "GameHUD",
    "render_mode": "screen_space",
    "sort_order": 0
  }
}

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AddUIElement

Add a UI element with UIRectTransformComponent and a widget component as a child of a canvas or another UI element.

Parameter	Type	Required	Description
element_name	string	Yes	Element entity name
widget_type	string	Yes	Widget component type (see below)
parent_guid	string	No	Parent canvas or UI element GUID
widget_data	object	No	Initial widget data (uses defaults if omitted)

Widget Types

Type	Description
UITextComponent	Text label
UIImageComponent	Image display
UIButtonComponent	Clickable button
UIPanelComponent	Background panel
UISliderComponent	Numeric slider
UIToggleComponent	Checkbox/switch
UIProgressBarComponent	Progress bar
UIInputFieldComponent	Text input
UIDropdownComponent	Dropdown selector

Example: HUD with Score and Health

[
  {
    "op": "CreateUICanvas",
    "params": { "canvas_name": "HUD", "sort_order": 0 }
  },
  {
    "op": "AddUIElement",
    "params": {
      "element_name": "ScoreLabel",
      "widget_type": "UITextComponent",
      "widget_data": {
        "text": "Score: 0",
        "font_size": 24,
        "color": { "x": 1, "y": 1, "z": 1, "w": 1 },
        "horizontal_alignment": "left"
      }
    }
  },
  {
    "op": "AddUIElement",
    "params": {
      "element_name": "HealthBar",
      "widget_type": "UIProgressBarComponent",
      "widget_data": {
        "fill_amount": 1.0,
        "fill_color": { "x": 0.8, "y": 0.1, "z": 0.1, "w": 1 },
        "direction": "left_to_right"
      }
    }
  }
]