uloop-simulate-mouse-ui

name	uloop-simulate-mouse-ui
description	Simulate PlayMode EventSystem UI mouse actions using screen coordinates. Use for UI clicks, long-presses, or drags from annotated screenshots.
context	fork

Task

Simulate mouse interaction on Unity PlayMode UI: $ARGUMENTS

Workflow

1. Ensure Unity is in PlayMode (use uloop control-play-mode --action Play if not)
2. Get UI element info: uloop screenshot --capture-mode rendering --annotate-elements --elements-only
3. Use the AnnotatedElements array to find the target element by Label, Name, or Path (A=frontmost, B=next, ...). Use Interaction to distinguish click targets from drag/drop/text targets, then use SimX/SimY directly as --x/--y coordinates.
4. Execute the appropriate uloop simulate-mouse-ui command
5. Take a screenshot to verify the result: uloop screenshot --capture-mode rendering --annotate-elements
6. Report what happened

Tool Reference

uloop simulate-mouse-ui --action <action> --x <x> --y <y> [options]

Parameters

Parameter	Type	Default	Description
--action	enum	Click	Click, Drag, DragStart, DragMove, DragEnd, LongPress
--x	number	0	Target X position in screen pixels (origin: top-left). For Drag action, this is the destination.
--y	number	0	Target Y position in screen pixels (origin: top-left). For Drag action, this is the destination.
--from-x	number	0	Start X position for Drag action. Drag starts here and moves to x,y.
--from-y	number	0	Start Y position for Drag action. Drag starts here and moves to x,y.
--drag-speed	number	2000	Drag speed in pixels per second (0 for instant). 2000 is fast (default), 200 is slow enough to watch. Applies to Drag, DragMove, and DragEnd actions.
--duration	number	0.5	Hold duration in seconds for LongPress action.
--button	enum	Left	Mouse button. Click and LongPress support Left, Right, and Middle. Drag actions support Left only; other buttons return an error.
--bypass-raycast	boolean	false	For Click, LongPress, Drag, and DragStart, bypass EventSystem raycast and dispatch pointer events directly to --target-path. Use when a raycast-blocking overlay visually covers the intended target.
--target-path	string	""	Hierarchy path of the target GameObject, for example Canvas/Panel/Button. Required when --bypass-raycast true is used with Click, LongPress, Drag, or DragStart; prefer AnnotatedElements[].Path from screenshot JSON.
--drop-target-path	string	""	Optional hierarchy path of a drop target for Drag or DragEnd, for example Canvas/DropZone. Use this when the drop zone is also behind a raycast blocker.

Actions

Action	Event Fired	Description
Click	PointerDown → PointerUp → PointerClick	Click at (x, y) with the selected --button
LongPress	PointerDown → (hold) → PointerUp	Press and hold at (x, y) for --duration seconds, then release. No PointerClick is fired.
Drag	BeginDrag → Drag×N → EndDrag	One-shot drag from (fromX, fromY) to (x, y) at the specified speed
DragStart	BeginDrag	Begin drag at (x, y) and hold
DragMove	Drag×N	Animate from current position to (x, y) at the specified speed
DragEnd	Drag×N → EndDrag	Animate to (x, y) at the specified speed, then release drag

Split Drag Rules

• DragStart must be called before DragMove or DragEnd
• DragEnd must be called to release an active drag — failing to call it leaves drag state stuck
• Calling DragMove or DragEnd without an active drag returns an error
• Drag, DragStart, DragMove, and DragEnd only support --button Left

Global Options (all optional, mutually exclusive)

Option	Description
--project-path <path>	Optional. Use only when the target Unity project is not the current directory.

Coordinate System

• Origin is top-left (0, 0)
• All positions are in screen pixels
• Get coordinates from AnnotatedElements JSON (SimX/SimY) — do NOT look up GameObject positions
• Clicking or long-pressing on empty space (no UI element) still succeeds with a message indicating no element was hit
• Dragging on empty space (no draggable UI element) returns Success = false
• --bypass-raycast true still uses coordinates for pointer event positions, but chooses the clicked, long-pressed, or dragged GameObject by --target-path
• If --target-path or --drop-target-path matches multiple active GameObjects, the command fails instead of choosing an arbitrary duplicate

Examples

# Click a button at screen position
uloop simulate-mouse-ui --action Click --x 400 --y 300

# Force-click a button behind a raycast blocker by path
uloop simulate-mouse-ui --action Click --x 400 --y 300 --bypass-raycast true --target-path "Canvas/Panel/Button"

# Force-long-press a button behind a raycast blocker by path
uloop simulate-mouse-ui --action LongPress --x 400 --y 300 --duration 3.0 --bypass-raycast true --target-path "Canvas/Panel/Button"

# Force-drag an item behind a raycast blocker by path
uloop simulate-mouse-ui --action Drag --from-x 400 --from-y 300 --x 600 --y 300 --bypass-raycast true --target-path "Canvas/Item"

# Force-drag and dispatch Drop to a blocked drop zone
uloop simulate-mouse-ui --action Drag --from-x 400 --from-y 300 --x 600 --y 300 --bypass-raycast true --target-path "Canvas/Item" --drop-target-path "Canvas/DropZone"

# Long-press a button for 3 seconds
uloop simulate-mouse-ui --action LongPress --x 400 --y 300 --duration 3.0

# One-shot drag (start to end in one call)
uloop simulate-mouse-ui --action Drag --from-x 400 --from-y 300 --x 600 --y 300

# Slow drag for visual inspection
uloop simulate-mouse-ui --action Drag --from-x 400 --from-y 300 --x 600 --y 300 --drag-speed 200

# Split drag with hold (for inspection between steps)
uloop simulate-mouse-ui --action DragStart --x 400 --y 300
uloop screenshot --window-name Game
uloop simulate-mouse-ui --action DragMove --x 500 --y 300
uloop simulate-mouse-ui --action DragEnd --x 600 --y 300

Prerequisites

• Unity must be in PlayMode
• Target scene must have an EventSystem GameObject
• UI elements must have a GraphicRaycaster on their Canvas
• If you need gameplay mouse input rather than UI pointer events, simulate-mouse-input assumes the project uses the New Input System; otherwise prefer execute-dynamic-code

Output

Returns JSON with:

• Success: Whether the operation succeeded
• Message: Status message (e.g. "Hit element: ButtonStart" or "No UI element under (x, y)")
• Action: Echoes which action was executed (Click, Drag, DragStart, DragMove, DragEnd, or LongPress)
• HitGameObjectName: Name of the topmost UI element under the pointer (nullable string; null if nothing was hit)
• PositionX: Target X coordinate that was used
• PositionY: Target Y coordinate that was used
• EndPositionX: Drag end X coordinate (nullable float; populated for drag actions only)
• EndPositionY: Drag end Y coordinate (nullable float; populated for drag actions only)

These are the only eight fields. There is no Button, Duration, DragSpeed, raycast list, or pointer-event log in the response — verify the visual outcome with a follow-up uloop screenshot --capture-mode rendering --annotate-elements.

Note: Click and LongPress on empty space (no UI element) still return Success = true with HitGameObjectName = null. Drag actions on empty space return Success = false.